Journal articles on the topic 'Ecologically relevant loci'

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1

Sun, Ying, and Haiwei Luo. "Homologous Recombination in Core Genomes Facilitates Marine Bacterial Adaptation." Applied and Environmental Microbiology 84, no. 11 (March 23, 2018): e02545-17. http://dx.doi.org/10.1128/aem.02545-17.

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ABSTRACTAcquisition of ecologically relevant genes is common among ocean bacteria, but whether it has a major impact on genome evolution in marine environments remains unknown. Here, we analyzed the core genomes of 16 phylogenetically diverse and ecologically relevant bacterioplankton lineages, each consisting of up to five genomes varying at the strain level. Statistical approaches identified from each lineage up to ∼50 loci showing anomalously high divergence at synonymous sites, which is best explained by recombination with distantly related organisms. The enriched gene categories in these outlier loci match well with the characteristics previously identified as the key phenotypes of these lineages. Examples are antibiotic synthesis and detoxification inPhaeobacter inhibens, exopolysaccharide production inAlteromonas macleodii, hydrocarbon degradation inMarinobacter hydrocarbonoclasticus, and cold adaptation inPseudoalteromonas haloplanktis. Intriguingly, the outlier loci feature polysaccharide catabolism inCellulophaga balticabut not inCellulophaga lytica, consistent with their primary habitat preferences in macroalgae and beach sands, respectively. Likewise, analysis ofProchlorococcusshowed that photosynthesis-related genes listed in the outlier loci are found only in the high-light-adapted ecotype and not in the low-light adapted ecotype. These observations strongly suggest that recombination with distant relatives is a key mechanism driving the ecological diversification among marine bacterial lineages.IMPORTANCEAcquisition of new metabolic genes has been known as an important mechanism driving bacterial evolution and adaptation in the ocean, but acquisition of novel alleles of existing genes and its potential ecological role have not been examined. Guided by population genetic theories, our genomic analysis showed that divergent allele acquisition is prevalent in phylogenetically diverse marine bacterial lineages and that the affected loci often encode metabolic functions that underlie the known ecological roles of the lineages under study.
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Weinig, Cynthia, Mark C. Ungerer, Lisa A. Dorn, Nolan C. Kane, Yuko Toyonaga, Solveig S. Halldorsdottir, Trudy F. C. Mackay, Michael D. Purugganan, and Johanna Schmitt. "Novel Loci Control Variation in Reproductive Timing inArabidopsis thalianain Natural Environments." Genetics 162, no. 4 (December 1, 2002): 1875–84. http://dx.doi.org/10.1093/genetics/162.4.1875.

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AbstractMolecular biologists are rapidly characterizing the genetic basis of flowering in model species such as Arabidopsis thaliana. However, it is not clear how the developmental pathways identified in controlled environments contribute to variation in reproductive timing in natural ecological settings. Here we report the first study of quantitative trait loci (QTL) for date of bolting (the transition from vegetative to reproductive growth) in A. thaliana in natural seasonal field environments and compare the results with those obtained under typical growth-chamber conditions. Two QTL specific to long days in the chamber were expressed only in spring-germinating cohorts in the field, and two loci specific to short days in the chamber were expressed only in fall-germinating cohorts, suggesting differential involvement of the photoperiod pathway in different seasonal environments. However, several other photoperiod-specific QTL with large effects in controlled conditions were undetectable in natural environments, indicating that expression of allelic variation at these loci was overridden by environmental factors specific to the field. Moreover, a substantial number of QTL with major effects on bolting date in one or more field environments were undetectable under controlled environment conditions. These novel loci suggest the involvement of additional genes in the transition to flowering under ecologically relevant conditions.
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Blom, Mozes P. K., Paul Horner, and Craig Moritz. "Convergence across a continent: adaptive diversification in a recent radiation of Australian lizards." Proceedings of the Royal Society B: Biological Sciences 283, no. 1832 (June 15, 2016): 20160181. http://dx.doi.org/10.1098/rspb.2016.0181.

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Recent radiations are important to evolutionary biologists, because they provide an opportunity to study the mechanisms that link micro- and macroevolution. The role of ecological speciation during adaptive radiation has been intensively studied, but radiations can arise from a diversity of evolutionary processes; in particular, on large continental landmasses where allopatric speciation might frequently precede ecological differentiation. It is therefore important to establish a phylogenetic and ecological framework for recent continental-scale radiations that are species-rich and ecologically diverse. Here, we use a genomic (approx. 1 200 loci, exon capture) approach to fit branch lengths on a summary-coalescent species tree and generate a time-calibrated phylogeny for a recent and ecologically diverse radiation of Australian scincid lizards; the genus Cryptoblepharus . We then combine the phylogeny with a comprehensive phenotypic dataset for over 800 individuals across the 26 species, and use comparative methods to test whether habitat specialization can explain current patterns of phenotypic variation in ecologically relevant traits. We find significant differences in morphology between species that occur in distinct environments and convergence in ecomorphology with repeated habitat shifts across the continent. These results suggest that isolated analogous habitats have provided parallel ecological opportunity and have repeatedly promoted adaptive diversification. By contrast, speciation processes within the same habitat have resulted in distinct lineages with relatively limited morphological variation. Overall, our study illustrates how alternative diversification processes might have jointly stimulated species proliferation across the continent and generated a remarkably diverse group of Australian lizards.
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Linder, Robert A., Fabian Seidl, Kimberly Ha, and Ian M. Ehrenreich. "The complex genetic and molecular basis of a model quantitative trait." Molecular Biology of the Cell 27, no. 1 (January 2016): 209–18. http://dx.doi.org/10.1091/mbc.e15-06-0408.

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Quantitative traits are often influenced by many loci with small effects. Identifying most of these loci and resolving them to specific genes or genetic variants is challenging. Yet, achieving such a detailed understanding of quantitative traits is important, as it can improve our knowledge of the genetic and molecular basis of heritable phenotypic variation. In this study, we use a genetic mapping strategy that involves recurrent backcrossing with phenotypic selection to obtain new insights into an ecologically, industrially, and medically relevant quantitative trait—tolerance of oxidative stress, as measured based on resistance to hydrogen peroxide. We examine the genetic basis of hydrogen peroxide resistance in three related yeast crosses and detect 64 distinct genomic loci that likely influence the trait. By precisely resolving or cloning a number of these loci, we demonstrate that a broad spectrum of cellular processes contribute to hydrogen peroxide resistance, including DNA repair, scavenging of reactive oxygen species, stress-induced MAPK signaling, translation, and water transport. Consistent with the complex genetic and molecular basis of hydrogen peroxide resistance, we show two examples where multiple distinct causal genetic variants underlie what appears to be a single locus. Our results improve understanding of the genetic and molecular basis of a highly complex, model quantitative trait.
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Ungerer, Mark C., Solveig S. Halldorsdottir, Michael D. Purugganan, and Trudy F. C. Mackay. "Genotype-Environment Interactions at Quantitative Trait Loci Affecting Inflorescence Development in Arabidopsis thaliana." Genetics 165, no. 1 (September 1, 2003): 353–65. http://dx.doi.org/10.1093/genetics/165.1.353.

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Abstract Phenotypic plasticity and genotype-environment interactions (GEI) play a prominent role in plant morphological diversity and in the potential functional capacities of plant life-history traits. The genetic basis of plasticity and GEI, however, is poorly understood in most organisms. In this report, inflorescence development patterns in Arabidopsis thaliana were examined under different, ecologically relevant photoperiod environments for two recombinant inbred mapping populations (Ler × Col and Cvi × Ler) using a combination of quantitative genetics and quantitative trait locus (QTL) mapping. Plasticity and GEI were regularly observed for the majority of 13 inflorescence traits. These observations can be attributable (at least partly) to variable effects of specific QTL. Pooled across traits, 12/44 (27.3%) and 32/62 (51.6%) of QTL exhibited significant QTL × environment interactions in the Ler × Col and Cvi × Ler lines, respectively. These interactions were attributable to changes in magnitude of effect of QTL more often than to changes in rank order (sign) of effect. Multiple QTL × environment interactions (in Cvi × Ler) clustered in two genomic regions on chromosomes 1 and 5, indicating a disproportionate contribution of these regions to the phenotypic patterns observed. High-resolution mapping will be necessary to distinguish between the alternative explanations of pleiotropy and tight linkage among multiple genes.
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Conith, Moira R., Yinan Hu, Andrew J. Conith, Maura A. Maginnis, Jacqueline F. Webb, and R. Craig Albertson. "Genetic and developmental origins of a unique foraging adaptation in a Lake Malawi cichlid genus." Proceedings of the National Academy of Sciences 115, no. 27 (June 18, 2018): 7063–68. http://dx.doi.org/10.1073/pnas.1719798115.

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Phenotypic novelties are an important but poorly understood category of morphological diversity. They can provide insights into the origins of phenotypic variation, but we know relatively little about their genetic origins. Cichlid fishes display remarkable diversity in craniofacial anatomy, including several novelties. One aspect of this variation is a conspicuous, exaggerated snout that has evolved in a single Malawi cichlid lineage and is associated with foraging specialization and increased ecological success. We examined the developmental and genetic origins for this phenotype and found that the snout is composed of two hypertrophied tissues: the intermaxillary ligament (IML), which connects the right and left sides of the upper jaw, and the overlying loose connective tissue. The IML is present in all cichlids, but in its exaggerated form it interdigitates with the more superficial connective tissue and anchors to the epithelium, forming a unique ligament–epithelial complex. We examined the Transforming growth factor β (Tgfβ) → Scleraxis (Scx) candidate pathway and confirmed a role for these factors in snout development. We demonstrate further that experimental up-regulation of Tgfβ is sufficient to produce an expansion of scx expression and concomitant changes in snout morphology. Genetic and genomic mapping show that core members of canonical Tgfβ signaling segregate with quantitative trait loci (QTL) for snout variation. These data also implicate a candidate for ligament development, adam12, which we confirm using the zebrafish model. Collectively, these data provide insights into ligament morphogenesis, as well as how an ecologically relevant novelty can arise at the molecular level.
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Strasburg, Jared L., Natasha A. Sherman, Kevin M. Wright, Leonie C. Moyle, John H. Willis, and Loren H. Rieseberg. "What can patterns of differentiation across plant genomes tell us about adaptation and speciation?" Philosophical Transactions of the Royal Society B: Biological Sciences 367, no. 1587 (February 5, 2012): 364–73. http://dx.doi.org/10.1098/rstb.2011.0199.

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Genome scans have become a common approach to identify genomic signatures of natural selection and reproductive isolation, as well as the genomic bases of ecologically relevant phenotypes, based on patterns of polymorphism and differentiation among populations or species. Here, we review the results of studies taking genome scan approaches in plants, consider the patterns of genomic differentiation documented and their possible causes, discuss the results in light of recent models of genomic differentiation during divergent adaptation and speciation, and consider assumptions and caveats in their interpretation. We find that genomic regions of high divergence generally appear quite small in comparisons of both closely and more distantly related populations, and for the most part, these differentiated regions are spread throughout the genome rather than strongly clustered. Thus, the genome scan approach appears well-suited for identifying genomic regions or even candidate genes that underlie adaptive divergence and/or reproductive barriers. We consider other methodologies that may be used in conjunction with genome scan approaches, and suggest further developments that would be valuable. These include broader use of sequence-based markers of known genomic location, greater attention to sampling strategies to make use of parallel environmental or phenotypic transitions, more integration with approaches such as quantitative trait loci mapping and measures of gene flow across the genome, and additional theoretical and simulation work on processes related to divergent adaptation and speciation.
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Loeschcke, Volker, Jesper G. Sørensen, and Torsten N. Kristensen. "Ecologically relevant stress resistance: from microarrays and quantitative trait loci to candidate genes — A research plan and preliminary results usingDrosophila as a model organism and climatic and genetic stress as model stresses." Journal of Biosciences 29, no. 4 (December 2004): 503–11. http://dx.doi.org/10.1007/bf02712122.

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9

Raimondo, Sandy, and Valery E. Forbes. "Moving beyond Risk Quotients: Advancing Ecological Risk Assessment to Reflect Better, More Robust and Relevant Methods." Ecologies 3, no. 2 (May 27, 2022): 145–60. http://dx.doi.org/10.3390/ecologies3020012.

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Under standard guidance for conducting Ecological Risk Assessments (ERAs), the risks of chemical exposure to diverse organisms are most often based on deterministic point estimates evaluated against safety-factor-based levels of concern (LOCs). While the science and guidance for mechanistic effect models (e.g., demographic, population, and agent-based) have long been demonstrated to provide more ecologically relevant effect endpoints upon which risk can be evaluated, their application in ERAs has been limited, particularly in the US. This special issue highlights the state of the science in effect modeling for ERAs through demonstrated application of the recently published Population modeling Guidance, Use, Interpretation, and Development for ERA (Pop-GUIDE). We introduce this issue with a perspective on why it is critical to move past the current application of deterministic endpoints and LOCs. We demonstrate how the current, widely used approaches contain extensive uncertainty that could be reduced considerably by applying models that account for species life histories and other important endogenous and exogenous factors critical to species sustainability. We emphasize that it is long past time to incorporate better, more robust, and ecologically relevant effect models into ERAs, particularly for chronic risk determination. The papers in this special issue demonstrate how mechanistic models that follow Pop-GUIDE better inform ERAs compared to the current standard practice.
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Bhatt, Supriya, Suvankar Biswas, Krithi Karanth, Bivash Pandav, and Samrat Mondol. "Genetic analyses reveal population structure and recent decline in leopards (Panthera pardus fusca) across the Indian subcontinent." PeerJ 8 (February 4, 2020): e8482. http://dx.doi.org/10.7717/peerj.8482.

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Background Large carnivores maintain the stability and functioning of ecosystems. Currently, many carnivore species face declining population sizes due to natural and anthropogenic pressures. The leopard, Panthera pardus, is probably the most widely distributed and highly adaptable large felid globally, still persisting in most of its historic range. However, we lack subspecies-level data on country or regional scale on population trends, as ecological monitoring approaches are difficult to apply on such wide-ranging species. We used genetic data from leopards sampled across the Indian subcontinent to investigate population structure and patterns of demographic decline. Methods We collected faecal samples from the Terai-Arc landscape of northern India and identified 56 unique individuals using a panel of 13 microsatellite markers. We merged this data with already available 143 leopard individuals and assessed genetic structure at country scale. Subsequently, we investigated the demographic history of each identified subpopulations and compared genetic decline analyses with countrywide local extinction probabilities. Results Our genetic analyses revealed four distinct subpopulations corresponding to Western Ghats, Deccan Plateau-Semi Arid, Shivalik and Terai region of the north Indian landscape, each with high genetic variation. Coalescent simulations with microsatellite loci revealed a possibly human-induced 75–90% population decline between ∼120–200 years ago across India. Population-specific estimates of genetic decline are in concordance with ecological estimates of local extinction probabilities in these subpopulations obtained from occupancy modeling of the historic and current distribution of leopards in India. Conclusions Our results confirm the population decline of a widely distributed, adaptable large carnivore. We re-iterate the relevance of indirect genetic methods for such species in conjunction with occupancy assessment and recommend that detailed, landscape-level ecological studies on leopard populations are critical to future conservation efforts. Our approaches and inference are relevant to other widely distributed, seemingly unaffected carnivores such as the leopard.
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Kurtz, Joachim, K. Mathias Wegner, Martin Kalbe, Thorsten B. H. Reusch, Helmut Schaschl, Dennis Hasselquist, and Manfred Milinski. "MHC genes and oxidative stress in sticklebacks: an immuno-ecological approach." Proceedings of the Royal Society B: Biological Sciences 273, no. 1592 (February 28, 2006): 1407–14. http://dx.doi.org/10.1098/rspb.2005.3450.

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Individual variation in the susceptibility to infection may result from the varying ability of hosts to specifically recognize different parasite strains. Alternatively, there could be individual host differences in fitness costs of immune defence. Although, these two explanations are not mutually exclusive, they have so far been treated in separate experimental approaches. To analyse potential relationships, we studied body condition and oxidative stress, which may reflect costs of immunity, in three-spined sticklebacks that had been experimentally exposed to three species of naturally occurring parasite. These sticklebacks differed in a trait, which is crucial to specific parasite defence, i.e. individual genetic diversity at major histocompatibility complex (MHC) class IIB loci. Oxidative stress was quantified as tissue acrolein, a technique that has been applied to questions of immuno-ecology for the first time. We measured gene expression at the MHC and other estimates of immune activation. We found that fish with high levels of MHC expression had poor condition and elevated oxidative stress. These results indicate that MHC-based specific immunity is connected with oxidative stress. They could, thus, also be relevant in the broader context of the evolution of sexually selected signals that are based on carotenoids and are, thus supposed to reflect oxidative stress resistance.
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Lombardo, Katharine, Andrea M. H. Towlerton, Alicia Morales, Sarah Gerdts, Innocent Mutyaba, Abrahams Omoding, Jackson Orem, Erica Sessle, Corey Casper, and Edus Warren. "Next Generation Sequencing of B Cell Antigen Receptors Expressed in African Endemic Burkitt Lymphoma." Blood 124, no. 21 (December 6, 2014): 1687. http://dx.doi.org/10.1182/blood.v124.21.1687.1687.

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Abstract The endemic form of Burkitt lymphoma (eBL), the most common pediatric cancer in sub-Saharan Africa, is the prototypic infection-related malignancy. Virtually 100% of eBL tumor cells carry Epstein-Barr virus (EBV) DNA, and eBL is closely ecologically associated with holoendemic P. falciparum malaria. The cell that undergoes transformation in eBL is an antigen-experienced B lymphocyte that has reached the germinal center and initiated the process of somatic hypermutation (SHM). The tumor cells in eBL express functional B-cell antigen receptors (BCRs), most commonly of the IgM isotype. The rearranged immunoglobulin heavy (IGH) and light (IGκ/λ) chain genes that encode Burkitt BCRs show evidence of SHM, demonstrating that eBL cells have uncoupled the processes of class switch recombination and SHM. Several lines of evidence suggest that BCR signaling pathways are active in eBL cells and that BCR signaling may contribute to the pathogenesis and maintenance of the disease. The uniquely rearranged BCR genes in eBL also represent a tumor-specific molecular signature that can be used to detect and quantitate eBL tumor cells in different tissue compartments. Therefore, Burkitt-associated BCRs have potential as both a disease biomarker and a therapeutic target. We utilized next-generation sequencing (NGS) to identify BCR gene rearrangements in eBL tumor cells obtained at the time of diagnosis from 22 patients, ages 4 to 12 (median: 7 years), with histologically confirmed Burkitt lymphoma who presented to the Uganda Cancer Institute in Kampala, Uganda. Thirteen of the patients were male and 9 were female; 3 patients were HIV-positive. Genomic DNA was isolated from cryopreserved tumor biopsies, and NGS of the IGH and IGκ/λ loci was performed to identify dominant BCR rearrangements in the eBL tumor cells. Sequence reads spanned a 130-nucleotide interval from the middle of framework region 3 (FR3) in the V gene segment to the 5’ region of the J gene segment. The reads captured the entirety of the CDR3 region. A single dominant IGH V-D-J rearrangement comprising >35% of all sequence reads was identified in 16 of the 22 samples. A single dominant IGκ or IGλ rearrangement was likewise seen in most cases with a single dominant IGH rearrangement. Two dominant but independent light chain rearrangements were seen in three eBL cases with a single dominant IGH rearrangement; whether both productive light chains are expressed at the RNA level is under active investigation. The utilization of IGH V- and J-gene segments in Burkitt-associated BCRs from this cohort of 22 patients was highly non-uniform, with utilization of IGHJ04-01 observed in 10 of the 16 cases with a single dominant IGH rearrangement. Analysis of BCR SHM patterns has revealed enrichment in CDRs as compared to FRs, suggesting antigen selection in eBL tumor cells, as well as a higher than expected rate of somatic mutations that create potential N-linked glycosylation sites. Deep sequencing of DNA extracted from peripheral blood mononuclear cells (PBMC) obtained at the time of diagnosis from 13 of the 22 patients identified sequences that were identical to the dominant IGH sequences observed in each patient’s tumor in 9 cases (69%). 5 of the 9 patients had early stage (Ziegler A) disease, demonstrating that Burkitt lymphoma cells commonly circulate in the blood. Current studies include sequencing of rearranged IGH genes present in PBMC after completion of primary therapy to determine if response is correlated with disappearance of the putative tumor-associated BCR sequences. Each eBL tumor sample is undergoing RNA analysis to confirm expression of the established dominant IGH and IGκ/λ rearrangements, as well as to determine the dominant BCR isotype. The complete light and heavy chain variable region sequences of the tumor-associated BCRs are being cloned by PCR with V gene leader peptide- and CDR3-specific primers to enable comprehensive assessment of SHM and BCR stereotypy. Identification of complete variable region sequences will also lay the foundation for synthesis of recombinant full-length membrane-associated and soluble forms of Burkitt BCRs. Reconstitution of Burkitt BCRs in vitro will allow evaluation of their antigenic specificity and signaling properties. Disclosures No relevant conflicts of interest to declare.
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Bradshaw, William E., Kevin J. Emerson, Julian M. Catchen, William A. Cresko, and Christina M. Holzapfel. "Footprints in time: comparative quantitative trait loci mapping of the pitcher-plant mosquito, Wyeomyia smithii." Proceedings of the Royal Society B: Biological Sciences 279, no. 1747 (September 26, 2012): 4551–58. http://dx.doi.org/10.1098/rspb.2012.1917.

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Identifying regions of the genome contributing to phenotypic evolution often involves genetic mapping of quantitative traits. The focus then turns to identifying regions of ‘major’ effect, overlooking the observation that traits of ecological or evolutionary relevance usually involve many genes whose individual effects are small but whose cumulative effect is large. Herein, we use the power of fully interfertile natural populations of a single species of mosquito to develop three quantitative trait loci (QTL) maps: one between two post-glacially diverged populations and two between a more ancient and a post-glacial population. All demonstrate that photoperiodic response is genetically a highly complex trait. Furthermore, we show that marker regressions identify apparently ‘non-significant’ regions of the genome not identified by composite interval mapping, that the perception of the genetic basis of adaptive evolution is crucially dependent upon genetic background and that the genetic basis for adaptive evolution of photoperiodic response is highly variable within contemporary populations as well as between anciently diverged populations.
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Rudman, Seth M., Sharon Greenblum, Rachel C. Hughes, Subhash Rajpurohit, Ozan Kiratli, Dallin B. Lowder, Skyler G. Lemmon, Dmitri A. Petrov, John M. Chaston, and Paul Schmidt. "Microbiome composition shapes rapid genomic adaptation of Drosophila melanogaster." Proceedings of the National Academy of Sciences 116, no. 40 (September 16, 2019): 20025–32. http://dx.doi.org/10.1073/pnas.1907787116.

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Population genomic data has revealed patterns of genetic variation associated with adaptation in many taxa. Yet understanding the adaptive process that drives such patterns is challenging; it requires disentangling the ecological agents of selection, determining the relevant timescales over which evolution occurs, and elucidating the genetic architecture of adaptation. Doing so for the adaptation of hosts to their microbiome is of particular interest with growing recognition of the importance and complexity of host–microbe interactions. Here, we track the pace and genomic architecture of adaptation to an experimental microbiome manipulation in replicate populations of Drosophila melanogaster in field mesocosms. Shifts in microbiome composition altered population dynamics and led to divergence between treatments in allele frequencies, with regions showing strong divergence found on all chromosomes. Moreover, at divergent loci previously associated with adaptation across natural populations, we found that the more common allele in fly populations experimentally enriched for a certain microbial group was also more common in natural populations with high relative abundance of that microbial group. These results suggest that microbiomes may be an agent of selection that shapes the pattern and process of adaptation and, more broadly, that variation in a single ecological factor within a complex environment can drive rapid, polygenic adaptation over short timescales.
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Card, Daren C., Richard H. Adams, Drew R. Schield, Blair W. Perry, Andrew B. Corbin, Giulia I. M. Pasquesi, Kristopher Row, et al. "Genomic Basis of Convergent Island Phenotypes in Boa Constrictors." Genome Biology and Evolution 11, no. 11 (October 23, 2019): 3123–43. http://dx.doi.org/10.1093/gbe/evz226.

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Abstract Convergent evolution is often documented in organisms inhabiting isolated environments with distinct ecological conditions and similar selective regimes. Several Central America islands harbor dwarf Boa populations that are characterized by distinct differences in growth, mass, and craniofacial morphology, which are linked to the shared arboreal and feast-famine ecology of these island populations. Using high-density RADseq data, we inferred three dwarf island populations with independent origins and demonstrate that selection, along with genetic drift, has produced both divergent and convergent molecular evolution across island populations. Leveraging whole-genome resequencing data for 20 individuals and a newly annotated Boa genome, we identify four genes with evidence of phenotypically relevant protein-coding variation that differentiate island and mainland populations. The known roles of these genes involved in body growth (PTPRS, DMGDH, and ARSB), circulating fat and cholesterol levels (MYLIP), and craniofacial development (DMGDH and ARSB) in mammals link patterns of molecular evolution with the unique phenotypes of these island forms. Our results provide an important genome-wide example for quantifying expectations of selection and convergence in closely related populations. We also find evidence at several genomic loci that selection may be a prominent force of evolutionary change—even for small island populations for which drift is predicted to dominate. Overall, while phenotypically convergent island populations show relatively few loci under strong selection, infrequent patterns of molecular convergence are still apparent and implicate genes with strong connections to convergent phenotypes.
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Ueguchi, Chiharu, Tomoko Ohta, Chiharu Seto, Tomomi Suzuki, and Takeshi Mizuno. "The leuO Gene Product Has a Latent Ability To Relieve bgl Silencing inEscherichia coli." Journal of Bacteriology 180, no. 1 (January 1, 1998): 190–93. http://dx.doi.org/10.1128/jb.180.1.190-193.1998.

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ABSTRACT The Escherichia coli bgl operon is of interest, since its expression is silent (phenotypically Bgl−), at least under standard laboratory conditions. Here we attempted to identify atrans-acting factor(s) that is presumably relevant to the regulation of bgl by a random insertion mutagenesis with mini-Tn10. These collected mutations, conferring the phenotype of Bgl+, were localized in three loci on the genetic map, two of which appeared to be hns andbglJ, which were previously implicated as the factors affecting the Bgl phenotype. The other locus at 1 to 2 min on the genetic map appeared to be a new one. In this case, the insertion mutation was found to be just in front of the leuO gene encoding a putative LysR-like DNA-binding protein. Genetic analyses revealed that overproduction of LeuO in the wild-type cells causes the phenotype of Bgl+. A leuO deletion mutant was also characterized in terms of expression of bgl. From these results, the possible function of LeuO in bglexpression will be discussed from an evolutionary and/or ecological point of view.
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Bottazzi, Patrick. "Work and Social-Ecological Transitions: A Critical Review of Five Contrasting Approaches." Sustainability 11, no. 14 (July 15, 2019): 3852. http://dx.doi.org/10.3390/su11143852.

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Going to work has become such a ritualized activity for the modern human that few people challenge its relevance from a sustainability perspective. Since the Industrial Revolution, the prospect of unlimited growth with the aim of jobs creation has been dramatically associated with a massive social-ecological degradation that puts the Earth system at risk. In recent decades, a number of heterodox theories and policies are reconsidering our relationship with work in view of contemporaneous social-ecological challenges. This paper offers critical review of five contrasting approaches. Those promoting ‘green jobs’ consider the possibility of transforming ecological constraints into economic opportunities by incentivising eco-efficient innovations and generating new jobs. Conversely, critical approaches, such as working-time reduction (WTR), labour environmentalism, political ecology of work, and contributive economy and justice, defend decommodifying work to liberate pro-social and pro-environmental behaviours. We additionally present two opposing scenarios mainly inspired by critical theories. One illustrates the root causes of systemic lock-in leading to the present social-ecological work-life degradation, while the other illustrates perspectives on the ‘politics of free time’ and contributive economy and justice oriented towards building capabilities, and workers’ emancipation and justice in search for more sustainable relationships with ecosystems.
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Espinoza, S., C. R. Magni, V. Martínez, W. Gapare, and C. Cordero. "Genetic diversity and differentiation of Chilean plantations of Pinus radiata D. Don using microsatellite DNA markers." Silvae Genetica 61, no. 1-6 (December 1, 2012): 221–28. http://dx.doi.org/10.1515/sg-2012-0028.

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AbstractRadiata pine (Pinus radiata D. Don) is the most important tree species in Chilean forest economy that was introduced to the country in 1892. Despite its economical end ecological relevance, no information about its genetic diversity is today available. Forty individuals of P. radiata, representing all populations in the Chilean radiata pine breeding program were genotyped with five microsatellite loci in order to determine genetic diversity and structure of Chilean plantations. The results of genetic diversity indicated that, after its introduction and mass planting, Chilean plantations of P. radiata has retained levels of genetic diversity similar to those of the natural populations of the species (HE=0.87, A=11.4). Genetic differentiation among populations (FST=0.04) was low, which means that the genetic variation present in radiata pine in Chile is partitioned among populations, indicating they are poorly differentiated. The structure analysis indicated the genetic base of the present plantations in Chile comes only from one provenance of the native populations. The genetic information provided important implications for the future breeding programs of P. radiata in Chile.
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Powell, Thomas H. Q., Glen Ray Hood, Meredith M. Doellman, Pheobe M. Deneen, James J. Smith, Stewart H. Berlocher, and Jeffrey L. Feder. "The Build-Up of Population Genetic Divergence along the Speciation Continuum during a Recent Adaptive Radiation of Rhagoletis Flies." Genes 13, no. 2 (January 30, 2022): 275. http://dx.doi.org/10.3390/genes13020275.

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New species form through the evolution of genetic barriers to gene flow between previously interbreeding populations. The understanding of how speciation proceeds is hampered by our inability to follow cases of incipient speciation through time. Comparative approaches examining different diverging taxa may offer limited inferences, unless they fulfill criteria that make the comparisons relevant. Here, we test for those criteria in a recent adaptive radiation of the Rhagoletis pomonella species group (RPSG) hypothesized to have diverged in sympatry via adaptation to different host fruits. We use a large-scale population genetic survey of 1568 flies across 33 populations to: (1) detect on-going hybridization, (2) determine whether the RPSG is derived from the same proximate ancestor, and (3) examine patterns of clustering and differentiation among sympatric populations. We find that divergence of each in-group RPSG taxon is occurring under current gene flow, that the derived members are nested within the large pool of genetic variation present in hawthorn-infesting populations of R. pomonella, and that sympatric population pairs differ markedly in their degree of genotypic clustering and differentiation across loci. We conclude that the RPSG provides a particularly robust opportunity to make direct comparisons to test hypotheses about how ecological speciation proceeds despite on-going gene flow.
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Exadactylos, Athanasios, Mark J. Rigby, Audrey J. Geffen, and John P. Thorpe. "Conservation aspects of natural populations and captive-bred stocks of turbot (Scophthalmus maximus) and Dover sole (Solea solea) using estimates of genetic diversity." ICES Journal of Marine Science 64, no. 6 (July 4, 2007): 1173–81. http://dx.doi.org/10.1093/icesjms/fsm086.

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Exadactylos, A., Rigby, M. J., Geffen, A. J., and Thorpe, J. P. 2007. Conservation aspects of natural populations and captive-bred stocks of turbot (Scophthalmus maximus) and Dover sole (Solea solea) using estimates of genetic diversity. – ICES Journal of marine Science, 64: 1173–1181. Population genetic analyses have been highly successful in predicting inter- and intraspecific evolutionary relationships, levels of gene flow, genetic divergence, and effective population sizes. Parameters estimated are evolutionary averages and are therefore relevant for addressing contemporary ecological or conservation issues. Changes in genetic variation within the range of a species may indicate patterns of population structure resulting from past ecological and demographic events that are otherwise difficult to infer, so may provide an insight into evolutionary development. Genetic data, drawn from 14 enzyme loci amplified from two populations of turbot (Scophthalmus maximus) and five populations of Dover sole (Solea solea) from the Irish Sea were used to examine population structure estimated from measures of genetic diversity. The aim was to provide an empirical assessment of whether artificial propagation poses a genetic threat to conservation of naturally spawning populations, and whether the fitness for natural spawning and rearing can be rapidly and substantially reduced or increased by artificial propagation. Because of prolonged overfishing, turbot and sole populations in the region are below natural levels, and survive in small local populations in fragmented habitats. Genetic data derived from allozymes have shown that populations are characterized by relatively low levels of genetic diversity. A hypothetical model supporting genetic population substructure, such as range expansion with founder-flush effects, and subsequent population decline with small effective population sizes was considered. Observations support our belief that conservation measures based on genetic diversity have to be developed to ensure the survival of this diverse gene pool.
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Oliveira, Daniela Pereira de, Jéssica Kalene Palheta Moraes, André Cristiano Silva Melo, Denilson Ricardo de Lucena Nunes, Ítalo Flexa Di Paolo, and Adriano Cesar Calandrini Braga. "Characteristics and Analyses of Strategic Factors in Reverse Channels of Açaí Pulp Production Waste in the Municipality of Castanhal/PA/ Caracterização e análise de fatores estratégicos nos canais reversos do resíduo da produção de polpa de açaí no município de Castanhal-PA." Brazilian Journal of Development 7, no. 7 (July 6, 2021): 66894–911. http://dx.doi.org/10.34117/bjdv7n7-117.

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When disposed of inappropriately, waste from the production of açaí pulp, originating from the açaí production chain, is the cause of many environmental, economic, and social problems. In an attempt to minimize impact, Reverse Logistics is an instrument of economic, environmental, and social development characterized by actions aimed at the treatment and reuse of waste, which is managed and moved through Reverse Channels. Consulted bibliography defines Strategic Factors capable of promoting the structuring and organization of waste for environmentally appropriate destination by different production sectors. This research analyzed economic, environmental/ecological, technological, logistical, and legislative strategic factors of the reverse channels for açaí production waste in the city of Castanhal/PA, as this municipality’s açaí pulp production is nationally relevant. For this purpose, it was necessary first to characterize local reverse channels, since bibliographic and documentary research did not yield relevant information on the subject. Field research—consisting of in loco observation, structured interviews, and application of online questionnaires to agents directly and indirectly involved—was fundamental to characterize the object of this study. As a result, we achieved the characterization of reverse channels, as well as their logistical resources and the stakeholders involved, starting from the generation of waste through to transportation and final destination, ending our analysis with the main forms of waste revaluation. Our research also allowed the identification and analysis of strategic factors capable of influencing the structuring and maintenance of activities in this reverse chain.
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Allewalt, Jessica P., Mary M. Bateson, Niels Peter Revsbech, Kimberly Slack, and David M. Ward. "Effect of Temperature and Light on Growth of and Photosynthesis by Synechococcus Isolates Typical of Those Predominating in the Octopus Spring Microbial Mat Community of Yellowstone National Park." Applied and Environmental Microbiology 72, no. 1 (January 2006): 544–50. http://dx.doi.org/10.1128/aem.72.1.544-550.2006.

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ABSTRACT Previous molecular analysis of the Octopus Spring cyanobacterial mat revealed numerous genetically distinct 16S rRNA sequences from predominant Synechococcus populations distantly related to the readily cultivated unicellular cyanobacterium Synechococcus lividus. Patterns in genotype distribution relative to temperature and light conditions suggested that the organisms contributing these 16S rRNA sequences may fill distinct ecological niches. To test this hypothesis, Synechococcus isolates were cultivated using a dilution and filtration approach and then shown to be genetically relevant to natural mat populations by comparisons of similarities of 16S rRNA genes and 16S-23S internal transcribed spacer (ITS) regions. Most isolates were identical or nearly identical at both loci to predominant mat genotypes; others showed 1- to 2-nucleotide differences at the 16S rRNA locus and even greater difference in ITS sequences. Isolates with predominant mat genotypes had distinct temperature ranges and optima for growth that were consistent with their distributions in the mat. Isolates with genotypes not previously detected or known to be predominant in the mat exhibited temperature ranges and optima that were not representative of predominant mat populations and also grew more slowly. Temperature effects on photosynthesis did not reflect temperature relations for growth. However, the isolate with the highest temperature optimum and upper limit was capable of performing photosynthesis at a higher temperature than other isolates. Growth rate and photosynthetic responses provided evidence for light acclimation but evidence of, at best, only subtle light adaptation.
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Dykstra, Hannah R., Stephanie R. Weldon, Adam J. Martinez, Jennifer A. White, Keith R. Hopper, George E. Heimpel, Mark K. Asplen, and Kerry M. Oliver. "Factors Limiting the Spread of the Protective Symbiont Hamiltonella defensa in Aphis craccivora Aphids." Applied and Environmental Microbiology 80, no. 18 (July 11, 2014): 5818–27. http://dx.doi.org/10.1128/aem.01775-14.

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ABSTRACTMany insects are associated with heritable symbionts that mediate ecological interactions, including host protection against natural enemies. The cowpea aphid,Aphis craccivora, is a polyphagous pest that harborsHamiltonella defensa, which defends against parasitic wasps. Despite this protective benefit, this symbiont occurs only at intermediate frequencies in field populations. To identify factors constrainingH. defensainvasion inAp. craccivora, we estimated symbiont transmission rates, performed fitness assays, and measured infection dynamics in population cages to evaluate effects of infection. Similar to results with the pea aphid,Acyrthosiphon pisum, we found no consistent costs to infection using component fitness assays, but we did identify clear costs to infection in population cages when no enemies were present. Maternal transmission rates ofH. defensainAp. craccivorawere high (ca. 99%) but not perfect. Transmission failures and infection costs likely limit the spread of protectiveH. defensainAp. craccivora. We also characterized several parameters ofH. defensainfection potentially relevant to the protective phenotype. We confirmed the presence ofH. defensain aphid hemolymph, where it potentially interacts with endoparasites, and performed real-time quantitative PCR (qPCR) to estimate symbiont and phage abundance during aphid development. We also examined strain variation ofH. defensaand its bacteriophage at multiple loci, and despite our lines being collected in different regions of North America, they were infected with a nearly identical strains ofH. defensaand APSE4 phage. The limited strain diversity observed for these defensive elements may result in relatively static protection profile for this defensive symbiosis.
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Rocha-Filho, L. C., C. Krug, C. I. Silva, and C. A. Garófalo. "Floral Resources Used by Euglossini Bees (Hymenoptera: Apidae) in Coastal Ecosystems of the Atlantic Forest." Psyche: A Journal of Entomology 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/934951.

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In spite of playing an important ecological role as pollinators of tropical ecosystems, orchid bees are still poorly known regarding their floral resources. Aiming at a better comprehension of the importance of different plants visited by the Euglossini and, consequently, their role in the maintenance and reproduction of plant species in tropical ecosystems, this study aimed at identifying the flowers visited by those bees in two different areas of the Atlantic Forest in the northern coast of the state of São Paulo, Brazil. Sampling was carried out from August 2007 to July 2009 in two coastal ecosystems in Ubatuba, Brazil. In order to obtain information on flower resources collected by Euglossini beesin loco, all bees observed on flowers were collected, pollinaria of Orchidaceae occasionally attached to the body of males were identified, and the pollinic analysis of 68 females was carried out. One hundred twelve bees from 14 species were associated to 105 plant species which represented pollen, nectar, resin, and fragrances sources. These data reinforce the relevance of orchid bees to the maintenance and reproductive success of many tropical plants.
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Ennami, Mounia, Fatima Zahra Briache, Joseph Mbasani Mansi, Fatima Gaboun, Lamiae Ghaouti, Loubna Belqadi, and Rachid Mentag. "Genetic Diversity of Moroccan Orobanche crenata Populations Revealed by Sequence-Related Amplified Polymorphism Markers." Journal of Agricultural Science 9, no. 4 (March 14, 2017): 164. http://dx.doi.org/10.5539/jas.v9n4p164.

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Orobanche crenata Forsk. is a root holoparasitic plant that affects legume species in Mediterranean basin especially in Northern Africa. This parasitic weed is particularly problematic in faba bean (Vicia faba L.) and lentil (Lens culinaris Medik.) fields. In Morocco, development of legume resistant/tolerant genotypes is considered the most economical and ecological control strategy against O. crenata. Efficient selection of resistant/tolerant cultivars requires prerequisite knowledge of the genetic diversity of the parasite. Thus, the present study focused on the assessment of the genetic diversity among and within Moroccan O. crenata populations, growing in faba bean fields, using Sequence-Related Amplified Polymorphism markers (SRAP). This marker system proved to be a powerful and an efficient tool for the evaluation of the genetic diversity among O. crenata populations. In fact, a total of 101 markers were identified and used for the Analysis of Molecular Variance (AMOVA), among which 98 bands were polymorphic (97.02%), indicating considerable genetic variation of these O. crenata populations. However, at population level, low level of polymorphic loci was observed with a percentage ranging between 41.58% and 67.33%. The Jaccard’s similarity coefficient and Principal Coordinate Analysis (PCoA) showed a clear differentiation among O. crenata samples according to the geographical origin of each population. AMOVA analysis revealed also a large extent of variation among O. crenata populations (60%; p < 0.010). Our outputs on molecular genetics of O. crenata combined with future epidemiological studies of these populations should clarify occurrence of O. crenata pathotypes and thereby validate the relevance of using multisite screening trials during breeding programs.
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Sola, Georgina, Verónica El Mujtar, Leonardo Gallo, Giovanni G. Vendramin, and Paula Marchelli. "Staying close: short local dispersal distances on a managed forest of two Patagonian Nothofagus species." Forestry: An International Journal of Forest Research 93, no. 5 (May 18, 2020): 652–61. http://dx.doi.org/10.1093/forestry/cpaa008.

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Abstract Understanding the impact of management on the dispersal potential of forest tree species is pivotal in the context of global change, given the implications of gene flow on species evolution. We aimed to determine the effect of logging on gene flow distances in two Nothofagus species from temperate Patagonian forests having high ecological relevance and wood quality. Therefore, a total of 778 individuals (mature trees and saplings) of Nothofagus alpina and N. obliqua, from a single plot managed 20 years ago (2.85 hectares), were mapped and genotyped at polymorphic nuclear microsatellite loci. Historical estimates of gene dispersal distance (based on fine-scale spatial genetic structure) and contemporary estimates of seed and pollen dispersal (based on spatially explicit mating models) were obtained. The results indicated restricted gene flow (gene distance ≤ 45 m, both pollen and seed), no selfing and significant seed and pollen immigration from trees located outside the studied plot but in the close surrounding area. The size of trees (diameter at breast height and height) was significantly associated with female and/or male fertility. The significant fine-scale spatial genetic structure was consistent with the restricted seed and pollen dispersal. Moreover, both estimates of gene dispersal (historical and contemporary) gave congruent results. This suggests that the recent history of logging within the study area has not significantly influenced on patterns of gene flow, which can be explained by the silviculture applied to the stand. The residual tree density maintained species composition, and the homogeneous spatial distribution of trees allowed the maintenance of gene dispersal. The short dispersal distance estimated for these two species has several implications both for understanding the evolution of the species and for defining management, conservation and restoration actions. Future replication of this study in other Nothofagus Patagonian forests would be helpful to validate our conclusions.
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Jacobs, Arne, Robyn Womack, Mel Chen, Karim Gharbi, and Kathryn Elmer. "Significant Synteny and Co-localization of Ecologically Relevant Quantitative Trait Loci Within and Across Species of Salmonid Fishes." Genetics, July 31, 2017, genetics.300093.2017. http://dx.doi.org/10.1534/genetics.117.300093.

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Coughlan, Jenn M., Maya Wilson Brown, and John H. Willis. "The genetic architecture and evolution of life-history divergence among perennials in the Mimulus guttatus species complex." Proceedings of the Royal Society B: Biological Sciences 288, no. 1948 (April 7, 2021). http://dx.doi.org/10.1098/rspb.2021.0077.

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Ecological divergence is a fundamental source of phenotypic diversity between closely related species, yet the genetic architecture of most ecologically relevant traits is poorly understood. Differences in elevation can impose substantial divergent selection on both complex, correlated suites of traits (such as life-history), as well as novel adaptations. We use the Mimulus guttatus species complex to assess if the divergence in elevation is accompanied by trait divergence in a group of closely related perennials and determine the genetic architecture of this divergence. We find that divergence in elevation is associated with differences in life-history, as well as a unique trait, the production of rhizomes. The divergence between two perennials is largely explained by few mid-to-large effect quantitative trait loci (QTLs). However, the presence of QTLs with correlated, but opposing effects on multiple traits leads to some hybrids with transgressive trait combinations. Lastly, we find that the genetic architecture of the ability to produce rhizomes changes through development, wherein most hybrids produce rhizomes, but only later in development. Our results suggest that elevational differences may shape life-history divergence between perennials, but aspects of the genetic architecture of divergence may have implications for hybrid fitness in nature.
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Matsusaka, Daniel, Daniele Filiault, Diego H. Sanchez, and Javier F. Botto. "Ultra-High-Density QTL Marker Mapping for Seedling Photomorphogenesis Mediating Arabidopsis Establishment in Southern Patagonia." Frontiers in Plant Science 12 (July 23, 2021). http://dx.doi.org/10.3389/fpls.2021.677728.

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Arabidopsis thaliana shows a wide range of genetic and trait variation among wild accessions. Because of its unparalleled biological and genomic resources, Arabidopsis has a high potential for the identification of genes underlying ecologically important complex traits, thus providing new insights on genome evolution. Previous research suggested that distinct light responses were crucial for Arabidopsis establishment in a peculiar ecological niche of southern Patagonia. The aim of this study was to explore the genetic basis of contrasting light-associated physiological traits that may have mediated the rapid adaptation to this new environment. From a biparental cross between the photomorphogenic contrasting accessions Patagonia (Pat) and Columbia (Col-0), we generated a novel recombinant inbred line (RIL) population, which was entirely next-generation sequenced to achieve ultra-high-density saturating molecular markers resulting in supreme mapping sensitivity. We validated the quality of the RIL population by quantitative trait loci (QTL) mapping for seedling de-etiolation, finding seven QTLs for hypocotyl length in the dark and continuous blue light (Bc), continuous red light (Rc), and continuous far-red light (FRc). The most relevant QTLs, Rc1 and Bc1, were mapped close together to chromosome V; the former for Rc and Rc/dark, and the latter for Bc, FRc, and dark treatments. The additive effects of both QTLs were confirmed by independent heterogeneous inbred families (HIFs), and we explored TZP and ABA1 as potential candidate genes for Rc1 and Bc1QTLs, respectively. We conclude that the Pat × Col-0 RIL population is a valuable novel genetic resource to explore other adaptive traits in Arabidopsis.
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Lange, Jeremy D., Héloïse Bastide, Justin B. Lack, and John E. Pool. "A Population Genomic Assessment of Three Decades of Evolution in a Natural Drosophila Population." Molecular Biology and Evolution 39, no. 2 (December 31, 2021). http://dx.doi.org/10.1093/molbev/msab368.

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Abstract Population genetics seeks to illuminate the forces shaping genetic variation, often based on a single snapshot of genomic variation. However, utilizing multiple sampling times to study changes in allele frequencies can help clarify the relative roles of neutral and non-neutral forces on short time scales. This study compares whole-genome sequence variation of recently collected natural population samples of Drosophila melanogaster against a collection made approximately 35 years prior from the same locality—encompassing roughly 500 generations of evolution. The allele frequency changes between these time points would suggest a relatively small local effective population size on the order of 10,000, significantly smaller than the global effective population size of the species. Some loci display stronger allele frequency changes than would be expected anywhere in the genome under neutrality—most notably the tandem paralogs Cyp6a17 and Cyp6a23, which are impacted by structural variation associated with resistance to pyrethroid insecticides. We find a genome-wide excess of outliers for high genetic differentiation between old and new samples, but a larger number of adaptation targets may have affected SNP-level differentiation versus window differentiation. We also find evidence for strengthening latitudinal allele frequency clines: northern-associated alleles have increased in frequency by an average of nearly 2.5% at SNPs previously identified as clinal outliers, but no such pattern is observed at random SNPs. This project underscores the scientific potential of using multiple sampling time points to investigate how evolution operates in natural populations, by quantifying how genetic variation has changed over ecologically relevant timescales.
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Laurentino, Telma G., Nicolas Boileau, Fabrizia Ronco, and Daniel Berner. "The EDA receptor (EDAR) is a candidate gene for lateral plate number variation in stickleback fish." G3 Genes|Genomes|Genetics, April 4, 2022. http://dx.doi.org/10.1093/g3journal/jkac077.

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Abstract Variation in lateral plating in stickleback fish represents a classical example of rapid and parallel adaptation in morphology. The underlying genetic architecture involves polymorphism at the ectodysplasin-A (EDA) gene. However, lateral plate number is influenced by additional loci that remain poorly characterized. Here we search for such loci by performing genome-wide differentiation mapping based on pooled whole-genome sequence data from a European stickleback population variable in the extent of lateral plating, while tightly controlling for the phenotypic effect of EDA. This suggests a new candidate locus, the EDA receptor (EDAR) gene, for which additional support is obtained by individual-level targeted Sanger sequencing and by comparing allele frequencies among natural populations. Overall, our study illustrates the power of pooled whole-genome sequencing for searching phenotypically relevant loci and opens opportunities for exploring the population genetics and ecological significance of a new candidate locus for stickleback armor evolution.
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Mastrogiorgio, Antonio, Francesca Zaninotto, Francesca Maggi, Emiliano Ricciardi, Nicola Lattanzi, and Andrea P. Malizia. "Enhancing Organizational Memory Through Virtual Memoryscapes: Does It Work?" Frontiers in Psychology 12 (August 12, 2021). http://dx.doi.org/10.3389/fpsyg.2021.683870.

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Enhancing cognitive memory through virtual reality represents an issue, that has never been investigated in organizational settings. Here, we compared a virtual memoryscape (treatment) – an immersive virtual environment used by subjects as a shared memory tool based on spatial navigation – with respect to the traditional individual-specific mnemonic tool based on the “method of loci” (control). A memory task characterized by high ecological validity was administered to 82 subjects employed by large banking group. Memory recall was measured, for both groups, immediately after the task (Phase 1) and one week later (Phase 2). Results show that (i) in Phase 1, the method of loci was more efficient in terms of recalling information than the to the virtual memoryscape; (ii) in Phase 2, there was no difference. Compared to the method of loci, the virtual memoryscape presents the advantages – relevant for organizations – of being collective, controllable, dynamic, and non-manipulable.
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Dornelles, André Z., Emily Boyd, Richard J. Nunes, Mike Asquith, Wiebren J. Boonstra, Izabela Delabre, J. Michael Denney, et al. "Towards a bridging concept for undesirable resilience in social-ecological systems." Global Sustainability 3 (2020). http://dx.doi.org/10.1017/sus.2020.15.

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Non-technical summary Resilience is a cross-disciplinary concept that is relevant for understanding the sustainability of the social and environmental conditions in which we live. Most research normatively focuses on building or strengthening resilience, despite growing recognition of the importance of breaking the resilience of, and thus transforming, unsustainable social-ecological systems. Undesirable resilience (cf. lock-ins, social-ecological traps), however, is not only less explored in the academic literature, but its understanding is also more fragmented across different disciplines. This disparity can inhibit collaboration among researchers exploring interdependent challenges in sustainability sciences. In this article, we propose that the term lock-in may contribute to a common understanding of undesirable resilience across scientific fields.
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Martinez Barrio, Alvaro, Sangeet Lamichhaney, Guangyi Fan, Nima Rafati, Mats Pettersson, He Zhang, Jacques Dainat, et al. "The genetic basis for ecological adaptation of the Atlantic herring revealed by genome sequencing." eLife 5 (May 3, 2016). http://dx.doi.org/10.7554/elife.12081.

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Ecological adaptation is of major relevance to speciation and sustainable population management, but the underlying genetic factors are typically hard to study in natural populations due to genetic differentiation caused by natural selection being confounded with genetic drift in subdivided populations. Here, we use whole genome population sequencing of Atlantic and Baltic herring to reveal the underlying genetic architecture at an unprecedented detailed resolution for both adaptation to a new niche environment and timing of reproduction. We identify almost 500 independent loci associated with a recent niche expansion from marine (Atlantic Ocean) to brackish waters (Baltic Sea), and more than 100 independent loci showing genetic differentiation between spring- and autumn-spawning populations irrespective of geographic origin. Our results show that both coding and non-coding changes contribute to adaptation. Haplotype blocks, often spanning multiple genes and maintained by selection, are associated with genetic differentiation.
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Moskalenko, Maria Ivanovna, Alexey Valerevich Polonikov, Inna Nikolaevna Sorokina, Tatyana Igorevna Yakunchenko, Yevgeniy Nikolayevich Krikun, and Irina Vasilevna Ponomarenko. "Gene-environment interactions between polymorphic loci of MMPs and obesity in essential hypertension in women." Problems of Endocrinology, February 6, 2020. http://dx.doi.org/10.14341/probl10236.

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Backgraund: The prevalence of essential hypertension (ЕH) is increasing every year, both in Russia and around the world. Genetic and environmental risk factors are involved in the development of hypertension, and obesity plays an important role. Therefore, the study of gene-ecological interactions in the development of hypertension seems to be relevant. Aims: to study the gene-environment interactions between polymorphic loci of MMP and obesity in essential hypertension in women. Materials and methods: The study was conducted in a case-control design. The sample included 584 subjects: 375 patients with EH and 209 women in the control group. All individuals included in the study were genotyped for eight polymorphic loci of MMPs. Statistical data processing was performed using the software "STATISTICA". The study of the gene-environmental interactions during the formation of hypertension was performed using the GMDR method (Generalized Multifactor Dimensionality Reduction, http://www.ssg.uab.edu/gmdr). Results: rs11568818 MMР7 and rs11225395 MMР8 polymorphic loci were found to be involved in the development of arterial hypertension in women without obesity (p0,050). Fifteen three-, four-, and five-factor models of gene-environmental interactions of 8 MMPs with obesity, associated with EH (p=0,001), were found. It is shown that the analyzed SNPs are located in the DNA regions that bind to histones, marking promoters and enhancers, in the region of hypersensitivity to DNAse-1, in the binding sites of regulatory proteins and transcription factors. The loci of MMPs rs17577, rs11568818, rs1320632 and rs11225395 have cis-eQTL-value. They affecting the expression of the genes of MMP7, SNX21, SLC12A5 and RP11-817J15.3. Conclusions: SNP rs11568818 MMP7 and rs11225395 MMP8 and gene-environmental interactions of MMPs rs1799750, rs243865, rs3025058, rs11568818, rs1320632, rs11225395, rs17577, rs652438 with obesity are involved in the development of essential hypertension in women.
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Riquet, Florentine, Christiane-Arnilda De Kuyper, Cécile Fauvelot, Laura Airoldi, Serge Planes, Simonetta Fraschetti, Vesna Mačić, Nataliya Milchakova, Luisa Mangialajo, and Lorraine Bottin. "Highly restricted dispersal in habitat-forming seaweed may impede natural recovery of disturbed populations." Scientific Reports 11, no. 1 (August 18, 2021). http://dx.doi.org/10.1038/s41598-021-96027-x.

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AbstractCystoseira sensu lato (Class Phaeophyceae, Order Fucales, Family Sargassaceae) forests play a central role in marine Mediterranean ecosystems. Over the last decades, Cystoseira s.l. suffered from a severe loss as a result of multiple anthropogenic stressors. In particular, Gongolaria barbata has faced multiple human-induced threats, and, despite its ecological importance in structuring rocky communities and hosting a large number of species, the natural recovery of G. barbata depleted populations is uncertain. Here, we used nine microsatellite loci specifically developed for G. barbata to assess the genetic diversity of this species and its genetic connectivity among fifteen sites located in the Ionian, the Adriatic and the Black Seas. In line with strong and significant heterozygosity deficiencies across loci, likely explained by Wahlund effect, high genetic structure was observed among the three seas (ENA corrected FST = 0.355, IC = [0.283, 0.440]), with an estimated dispersal distance per generation smaller than 600 m, both in the Adriatic and Black Sea. This strong genetic structure likely results from restricted gene flow driven by geographic distances and limited dispersal abilities, along with genetic drift within isolated populations. The presence of genetically disconnected populations at small spatial scales (< 10 km) has important implications for the identification of relevant conservation and management measures for G. barbata: each population should be considered as separated evolutionary units with dedicated conservation efforts.
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Riemann, Lasse, Eyal Rahav, Uta Passow, Hans-Peter Grossart, Dirk de Beer, Isabell Klawonn, Meri Eichner, Mar Benavides, and Edo Bar-Zeev. "Planktonic Aggregates as Hotspots for Heterotrophic Diazotrophy: The Plot Thickens." Frontiers in Microbiology 13 (April 6, 2022). http://dx.doi.org/10.3389/fmicb.2022.875050.

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Biological dinitrogen (N2) fixation is performed solely by specialized bacteria and archaea termed diazotrophs, introducing new reactive nitrogen into aquatic environments. Conventionally, phototrophic cyanobacteria are considered the major diazotrophs in aquatic environments. However, accumulating evidence indicates that diverse non-cyanobacterial diazotrophs (NCDs) inhabit a wide range of aquatic ecosystems, including temperate and polar latitudes, coastal environments and the deep ocean. NCDs are thus suspected to impact global nitrogen cycling decisively, yet their ecological and quantitative importance remain unknown. Here we review recent molecular and biogeochemical evidence demonstrating that pelagic NCDs inhabit and thrive especially on aggregates in diverse aquatic ecosystems. Aggregates are characterized by reduced-oxygen microzones, high C:N ratio (above Redfield) and high availability of labile carbon as compared to the ambient water. We argue that planktonic aggregates are important loci for energetically-expensive N2 fixation by NCDs and propose a conceptual framework for aggregate-associated N2 fixation. Future studies on aggregate-associated diazotrophy, using novel methodological approaches, are encouraged to address the ecological relevance of NCDs for nitrogen cycling in aquatic environments.
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Sandoval-Castillo, Jonathan, Luciano B. Beheregaray, and Maren Wellenreuther. "Genomic prediction of growth in a commercially, recreationally, and culturally important marine resource, the Australian snapper (Chrysophrys auratus)." G3 Genes|Genomes|Genetics 12, no. 3 (January 20, 2022). http://dx.doi.org/10.1093/g3journal/jkac015.

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Abstract Growth is one of the most important traits of an organism. For exploited species, this trait has ecological and evolutionary consequences as well as economical and conservation significance. Rapid changes in growth rate associated with anthropogenic stressors have been reported for several marine fishes, but little is known about the genetic basis of growth traits in teleosts. We used reduced genome representation data and genome-wide association approaches to identify growth-related genetic variation in the commercially, recreationally, and culturally important Australian snapper (Chrysophrys auratus, Sparidae). Based on 17,490 high-quality single-nucleotide polymorphisms and 363 individuals representing extreme growth phenotypes from 15,000 fish of the same age and reared under identical conditions in a sea pen, we identified 100 unique candidates that were annotated to 51 proteins. We documented a complex polygenic nature of growth in the species that included several loci with small effects and a few loci with larger effects. Overall heritability was high (75.7%), reflected in the high accuracy of the genomic prediction for the phenotype (small vs large). Although the single-nucleotide polymorphisms were distributed across the genome, most candidates (60%) clustered on chromosome 16, which also explains the largest proportion of heritability (16.4%). This study demonstrates that reduced genome representation single-nucleotide polymorphisms and the right bioinformatic tools provide a cost-efficient approach to identify growth-related loci and to describe genomic architectures of complex quantitative traits. Our results help to inform captive aquaculture breeding programs and are of relevance to monitor growth-related evolutionary shifts in wild populations in response to anthropogenic pressures.
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Pascall, David J., Matthew C. Tinsley, Bethany L. Clark, Darren J. Obbard, and Lena Wilfert. "Virus Prevalence and Genetic Diversity Across a Wild Bumblebee Community." Frontiers in Microbiology 12 (April 22, 2021). http://dx.doi.org/10.3389/fmicb.2021.650747.

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Viruses are key population regulators, but we have limited knowledge of the diversity and ecology of viruses. This is even the case in wild host populations that provide ecosystem services, where small fitness effects may have major ecological impacts in aggregate. One such group of hosts are the bumblebees, which have a major role in the pollination of food crops and have suffered population declines and range contractions in recent decades. In this study, we investigate the diversity of four recently discovered bumblebee viruses (Mayfield virus 1, Mayfield virus 2, River Liunaeg virus, and Loch Morlich virus), and two previously known viruses that infect both wild bumblebees and managed honeybees (Acute bee paralysis virus and Slow bee paralysis virus) from isolates in Scotland. We investigate the ecological and environmental factors that determine viral presence and absence. We show that the recently discovered bumblebee viruses were more genetically diverse than the viruses shared with honeybees. Coinfection is potentially important in shaping prevalence: we found a strong positive association between River Liunaeg virus and Loch Morlich virus presence after controlling for host species, location and other relevant ecological variables. We tested for a relationship between environmental variables (temperature, UV radiation, wind speed, and prevalence), but as we had few sampling sites, and thus low power for site-level analyses, we could not conclude anything regarding these variables. We also describe the relationship between the bumblebee communities at our sampling sites. This study represents a first step in the description of predictors of bumblebee infection in the wild.
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40

Arnold, A. Elizabeth, Alison H. Harrington, Yu-Ling Huang, Jana M. U'Ren, Nicholas C. Massimo, Victoria Knight-Connoni, and Patrik Inderbitzin. "Coniochaeta elegans sp. nov., Coniochaeta montana sp. nov. and Coniochaeta nivea sp. nov., three new species of endophytes with distinctive morphology and functional traits." International Journal of Systematic and Evolutionary Microbiology 71, no. 11 (November 3, 2021). http://dx.doi.org/10.1099/ijsem.0.005003.

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A growing interest in fungi that occur within symptom-less plants and lichens (endophytes) has uncovered previously uncharacterized species in diverse biomes worldwide. In many temperate and boreal forests, endophytic Coniochaeta (Sacc.) Cooke (Coniochaetaceae, Coniochaetales, Sordariomycetes, Ascomycota) are commonly isolated on standard media, but rarely are characterized. We examined 26 isolates of Coniochaeta housed at the Gilbertson Mycological Herbarium. The isolates were collected from healthy photosynthetic tissues of conifers, angiosperms, mosses and lichens in Canada, Sweden and the United States. Their barcode sequences (nuclear ribosomal internal transcribed spacer and 5.8S; ITS rDNA) were ≤97% similar to any documented species available through GenBank. Phylogenetic analyses based on two loci (ITS rDNA and translation elongation factor 1-alpha) indicated that two isolates represented Coniochaeta cymbiformispora, broadening the ecological niche and geographic range of a species known previously from burned soil in Japan. The remaining 24 endophytes represented three previously undescribed species that we characterize here: Coniochaeta elegans sp. nov., Coniochaeta montana sp. nov. and Coniochaeta nivea sp. nov. Each has a wide host range, including lichens, bryophytes and vascular plants. C. elegans sp. nov. and C. nivea sp. nov. have wide geographic ranges. C. montana sp. nov. occurs in the Madrean biome of Arizona (USA), where it is sympatric with the other species described here. All three species display protease, chitinase and cellulase activity in vitro. Overall, this study provides insight into the ecological and evolutionary diversity of Coniochaeta and suggests that these strains may be amenable for studies of traits relevant to a horizontally transmitted, symbiotic lifestyle.
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Luo, Yu-Ting, Di-An Fang, Yan-Feng Zhou, Dong-Po Xu, Yun-Xin Peng, Min-Ying Zhang, Cheng-Cheng Mao, Xue-Mei Tang, Jun Xu, and Yang You. "Genetic Diversity, Habitat Relevance and Conservation Strategies of the Silver Carp in the Yangtze River by Simple Sequence Repeat." Frontiers in Ecology and Evolution 10 (May 26, 2022). http://dx.doi.org/10.3389/fevo.2022.850183.

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The spatial distribution of fish individuals is affected by habitat conditions and species ecological characteristics, and it also reflects the longtime adaptation to habitat at the phenotypic and genotypic level. As a typical river-lake migratory fish species, the silver carp habitat selection was determined by its migration preference and genetic features. In this study, 15 microsatellite fluorescent markers combined with capillary electrophoresis were used to analyze the genetic diversity, genetic differentiation, and structure of nature silver carp populations in the Sanzhou (SZ), Hukou (HK), Anqing (AQ), Zhenjiang (ZJ), and Rugao (RG) sections of the Yangtze River. The results showed that 15 microsatellite loci exhibited medium to high polymorphisms. The overall genetic diversity in the Yangtze River was high, with the average value of Shannon’s information index ranging from 1.559 to 1.668. The numbers of alleles (Ne) ranged from 1.630 to 10.100. The expected heterozygosity (He, 0.690–0.721) was higher than observed heterozygosity (Ho, 0.598–0.646), and the genetic variation mainly originated from within the population (94.69%). However, the entire population was in the state of heterozygous deletion, and HK, RG populations encountered the risk of inbreeding risk (F &gt; 1). Interestingly, there was a distinct genetic structure for the population in the HK section, which indicated that local population has occurred to the silver carp in this river section, and they may also possess aggregation characteristics specific to the river-lake-connected (RLC) habitat. The results mostly support the conclusion that the RLC habitat is essential for geographic population formation. The potential impact of special habitats on natural populations should be considered, and continuous surveys on population dynamics should be performed.
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42

Brunet, Maéva, Nolwen Le Duff, Tristan Barbeyron, and François Thomas. "Consuming fresh macroalgae induces specific catabolic pathways, stress reactions and Type IX secretion in marine flavobacterial pioneer degraders." ISME Journal, May 19, 2022. http://dx.doi.org/10.1038/s41396-022-01251-6.

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AbstractMacroalgae represent huge amounts of biomass worldwide, largely recycled by marine heterotrophic bacteria. We investigated the strategies of bacteria within the flavobacterial genus Zobellia to initiate the degradation of whole algal tissues, which has received little attention compared to the degradation of isolated polysaccharides. Zobellia galactanivorans DsijT has the capacity to use fresh brown macroalgae as a sole carbon source and extensively degrades algal tissues via the secretion of extracellular enzymes, even in the absence of physical contact with the algae. Co-cultures experiments with the non-degrading strain Tenacibaculum aestuarii SMK-4T showed that Z. galactanivorans can act as a pioneer that initiates algal breakdown and shares public goods with other bacteria. A comparison of eight Zobellia strains, and strong transcriptomic shifts in Z. galactanivorans cells using fresh macroalgae vs. isolated polysaccharides, revealed potential overlooked traits of pioneer bacteria. Besides brown algal polysaccharide degradation, they notably include oxidative stress resistance proteins, type IX secretion system proteins and novel uncharacterized polysaccharide utilization loci. Overall, this work highlights the relevance of studying fresh macroalga degradation to fully understand the metabolic and ecological strategies of pioneer microbial degraders, key players in macroalgal biomass remineralization.
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Karcher, Nicolai, Eleonora Nigro, Michal Punčochář, Aitor Blanco-Míguez, Matteo Ciciani, Paolo Manghi, Moreno Zolfo, et al. "Genomic diversity and ecology of human-associated Akkermansia species in the gut microbiome revealed by extensive metagenomic assembly." Genome Biology 22, no. 1 (July 14, 2021). http://dx.doi.org/10.1186/s13059-021-02427-7.

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Abstract Background Akkermansia muciniphila is a human gut microbe with a key role in the physiology of the intestinal mucus layer and reported associations with decreased body mass and increased gut barrier function and health. Despite its biomedical relevance, the genomic diversity of A. muciniphila remains understudied and that of closely related species, except for A. glycaniphila, unexplored. Results We present a large-scale population genomics analysis of the Akkermansia genus using 188 isolate genomes and 2226 genomes assembled from 18,600 metagenomes from humans and other animals. While we do not detect A. glycaniphila, the Akkermansia strains in the human gut can be grouped into five distinct candidate species, including A. muciniphila, that show remarkable whole-genome divergence despite surprisingly similar 16S rRNA gene sequences. These candidate species are likely human-specific, as they are detected in mice and non-human primates almost exclusively when kept in captivity. In humans, Akkermansia candidate species display ecological co-exclusion, diversified functional capabilities, and distinct patterns of associations with host body mass. Analysis of CRISPR-Cas loci reveals new variants and spacers targeting newly discovered putative bacteriophages. Remarkably, we observe an increased relative abundance of Akkermansia when cognate predicted bacteriophages are present, suggesting ecological interactions. A. muciniphila further exhibits subspecies-level genetic stratification with associated functional differences such as a putative exo/lipopolysaccharide operon. Conclusions We uncover a large phylogenetic and functional diversity of the Akkermansia genus in humans. This variability should be considered in the ongoing experimental and metagenomic efforts to characterize the health-associated properties of A. muciniphila and related bacteria.
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Ojeda-Granados, Claudia, Paolo Abondio, Alice Setti, Stefania Sarno, Guido Alberto Gnecchi-Ruscone, Eduardo González-Orozco, Sara De Fanti, et al. "Dietary, Cultural, and Pathogens-Related Selective Pressures Shaped Differential Adaptive Evolution among Native Mexican Populations." Molecular Biology and Evolution 39, no. 1 (October 1, 2021). http://dx.doi.org/10.1093/molbev/msab290.

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Abstract Native American genetic ancestry has been remarkably implicated with increased risk of diverse health issues in several Mexican populations, especially in relation to the dramatic changes in environmental, dietary, and cultural settings they have recently undergone. In particular, the effects of these ecological transitions and Westernization of lifestyles have been investigated so far predominantly on Mestizo individuals. Nevertheless, indigenous groups, rather than admixed Mexicans, have plausibly retained the highest proportions of genetic components shaped by natural selection in response to the ancient milieu experienced by Mexican ancestors during their pre-Columbian evolutionary history. These formerly adaptive variants have the potential to represent the genetic determinants of some biological traits that are peculiar to Mexican people, as well as a reservoir of loci with possible biomedical relevance. To test such a hypothesis, we used genome-wide genotype data to infer the unique adaptive evolution of Native Mexican groups selected as reasonable descendants of the main pre-Columbian Mexican civilizations. A combination of haplotype-based and gene-network analyses enabled us to detect genomic signatures ascribable to polygenic adaptive traits plausibly evolved by the main genetic clusters of Mexican indigenous populations to cope with local environmental and/or cultural conditions. Some of these adaptations were found to play a role in modulating the susceptibility/resistance of these groups to certain pathological conditions, thus providing new evidence that diverse selective pressures have contributed to shape the current biological and disease-risk patterns of present-day Native and Mestizo Mexican populations.
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Triest, Ludwig, Jasper Dierick, Thi Thuy Hang Phan, Quang Doc Luong, Nguyen Quang Huy, and Tim Sierens. "Low Genetic Connectivity of Strongly Inbred Ruppia brevipedunculata in Aquaculture Dominated Lagoons (Viet Nam)." Frontiers in Conservation Science 2 (September 17, 2021). http://dx.doi.org/10.3389/fcosc.2021.723376.

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Lagoonal environments exhibit high levels of instability depending on hydrological, climatic and ecological factors, thereby influencing the distribution and structure of submerged plant communities. Conditions typically fluctuate widely due to the interaction of freshwater from rivers with saltwater from the sea, as well as from aquaculture activities that together influence submerged hydrophyte community spatial and temporal variability depending on plant survival strategies. Ruppia species feature either underwater pollination mediated by an air bubble or by the release of pollen floating at the water surface, the former promoting self-pollination. Tropical Asian Ruppia brevipedunculata Yu and den Hartog was assumed to pollinate below the water surface and identified as a separate lineage among selfed Ruppia taxa. We used nine nuclear microsatellites to estimate inbreeding levels and connectivity of R. brevipedunculata within a large SE Asian lagoon complex. Ruppia brevipedunculata meadows were strongly inbred as could be derived from the many monomorphic or totally fixed loci for unique alleles in different parts of the lagoon, which appears consistent with selfing behavior. Those from aquaculture ponds were highly inbred (FIS = 0.620), though less than open lagoon sites that showed nearly total inbreeding (FIS = 0.942). Ruppia brevipedunculata from two major lagoon parts were highly differentiated with spatially structured gene pools and a strong barrier between parts of the lagoon over a 30 km distance. Migration-n analysis indicated unidirectional though limited gene flow and following potential hydrological connectivity. Overall, private alleles under homozygote conditions explained a stronger genetic differentiation of populations situated inside aquaculture ponds than of open lagoon populations. Kinship values were only relevant up to 5 km distance in the open lagoon. Within a confined area of aquaculture ponds featuring dense vegetation in stagnant water, there would be opportunity for mixed pollination, thereby explaining the higher diversity of unique multilocus genotypes of aquaculture pond habitats. Low connectivity prevents gene pools to homogenize however promoted sites with private alleles across the lagoon. Complex hydrodynamic systems and human-made habitats enclosed by physical structures impose barriers for propagule dispersal though may create refugia and contribute to conserving regional genetic diversity.
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46

Kiyotani, Ilana Barreto, Fabiana Gomes Sousa, and Amada Gama Tavares. "Turismo em Unidades de Conservação: o Jardim Botânico Benjamin Maranhão, João Pessoa (PB)." Revista Brasileira de Ecoturismo (RBEcotur) 8, no. 5 (November 30, 2015). http://dx.doi.org/10.34024/rbecotur.2015.v8.6448.

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Atividades sustentáveis têm se tornado o foco de muitos países, principalmente no que diz respeito aos aspectos econômicos e ambientais. A implantação de Unidades de Conservação, como os Jardins Botânicos, e a realização do turismo nesses ambientes têm se mostrado opções para o alcance da sustentabilidade e da consciência ambiental. O objetivo deste trabalho é apresentar, dentro do contexto das Unidades de Conservação, das Áreas de Preservação Permanente e dos Jardins Botânicos, os usos turísticos do Jardim Botânico Benjamim Maranhão (JBBM), em João Pessoa (PB). A escolha leva em conta sua relevância para a cidade no que diz respeito ao incentivo à consciência ambiental, assim como sua representação de maior área de floresta nativa urbana do País. Foram usadas pesquisas bibliográficas, numa abordagem qualitativa, e visitas in loco ao JBBM. O caso relatado tem proporcionado visitação, lazer e educação a turistas e visitantes. Através das atividades realizadas, majoritariamente trilhas, a consciência ecológica e ambiental é instigada, proporcionando ao visitante maior conhecimento e interatividade com o espaço. No entanto, em relação a suas características ambientais, percebe-se que o JBBM poderia implementar mais ações, como atividades mais incisivas de interpretação ambiental; parcerias que favoreçam mais visitações e; práticas pedagógicas relacionadas a outros campos de estudo, como sociologia e história. No que tange a práticas turísticas, além do ecoturismo e do turismo pedagógico, poder-se-ia pensar em outros segmentos do turismo, como de aventura; de eventos; científico e; de experiência. Tourism in Protected Areas: the Botanical Gardens Benjamin Maranhao, Joao Pessoa (PB, Brazil) ABSTRACT Sustainable activities have become the focus of many countries, particularly with regard to economic and environmental aspects. The establishment of Conservation Units, such as Botanical Gardens, and the realization of tourism in these environments have proven options to achieve sustainability and environmental awareness. The aim of this paper is to present, within the context of the Conservation Units, the Permanent Preservation Areas and the Botanical Gardens, the touristic uses of the Jardim Botânico Benjamin Maranhão (JBBM) in João Pessoa (PB). The choice considers its relevance to the city with regard to encouraging environmental awareness, as well as its representation being the biggest urban area of native forest in the country. Library research was used, in a qualitative approach, and also visits to the JBBM. The reported case has provided visitation, recreation and education to tourists and visitors. In all the three activities, mostly trails, the ecological and environmental awareness is instigated, giving visitors a bigger knowledge and interaction with the space. However, in relation to their environmental characteristics, it is noted that the JBBM could implement more actions, such as more forceful activities of environmental interpretation; partnerships that promote more visitations and; pedagogical practices related to other fields of study, such as sociology and history. In terms of tourism practices, in addition to the ecotourism and educational tourism, it is possible to think about other tourism segments, such as adventure; events; scientific and; tourism of experience. KEYWORDS: Tourism; Conservation Units; Jardim Botânico Benjamim Maranhão.
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Fonseca, Janaina Maria Andrade Aires, Stella Maria Carvalho de Melo, and Wesley Gomes de Carvalho. "O Ecoturismo como alternativa sustentável para gestão da RPPN Catedral do Jalapão (TO)." Revista Brasileira de Ecoturismo (RBEcotur) 11, no. 1 (February 28, 2018). http://dx.doi.org/10.34024/rbecotur.2018.v11.6663.

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A prática do turismo nas Unidades de Conservação (UC’s) vem crescendo nos últimos anos. No Brasil, grande parte dos atrativos ecoturísticos encontra-se nas UC’s, onde as Reservas Particulares do Patrimônio Natural (RPPN’s) representam uma categoria de caráter privado. Essas unidades seguem uma tendência mundial de expansão dos esforços privados na conservação da biodiversidade, cujo uso compatível, por meio do turismo, é permitido, mediante planejamento e manejo adequados. O segmento do turismo que explora as UC’s é chamado de ecoturismo, e começa a ser realizado em uma RPPN no Estado do Tocantins, Brasil. O objetivo deste estudo é investigar a prática do ecoturismo como alternativa para as RPPN’s através de um estudo de caso na RPPN Catedral do Jalapão, analisando a gestão da atividade, o perfil e o fluxo de visitantes do local. Os procedimentos metodológicos utilizados para o desenvolvimento da pesquisa são pesquisa bibliográfica e de campo, através de visitas in loco, entrevista com o gestor e aplicação de questionários com os visitantes. A pesquisa foi norteada pela questão da possibilidade de o ecoturismo vir a ser uma alternativa para a gestão sustentável de Unidades de Conservação de propriedade privada, cujos resultados demonstram tendências e práticas diversas sendo desenvolvidas nesses ambientes. Com esta pesquisa, verificou-se que a RPPN utiliza de uma arquitetura sustentável nas suas instalações, e que os principais motivos que levaram a sua criação foi a proteção da fauna e flora local e relevância ecológica da sua localização. Percebeu-se que os visitantes buscam curtir na natureza que a região proporciona, além das práticas de atividades de ecoturismo, promovendo um contato com o meio ambiente local. Assim, constatou-se que a Catedral do Jalapão tem buscado através de suas práticas, cumprir com o papel socioambiental para o qual foi definida, sendo um modelo de sustentabilidade e boas práticas associadas ao ecoturismo. Ecotourism as a sustainable alternative for the management of the RPPN Catedral do Jalapão (TO, Brazil) ABSTRACT The practice of tourism in Protected Areas (PA) has been growing in recent years. In Brazil, most of the ecotourism attractions are found in the PAs, where Private Reserves of Natural Patrimony (RPPN's) represent a category of private sphere. These units follow a worldwide trend of expanding private efforts to conserve biodiversity, whose compatible use through tourism is permitted through appropriate planning and management. The tourism segment that explores PAs is called ecotourism, and begins to be held in an RPPN in the state of Tocantins, Brazil. The objective of this study is to investigate the practice of ecotourism as an alternative to the RPPN's through a case study in the RPPN Catedral do Japalão, analyzing the activity management, the profile and the flow of visitors to the area. The methodological procedures used for the development of the research are bibliographic and field research, through on-site visits, interview with the manager and application of questionnaires with the visitors. The research was guided by the question of the possibility of ecotourism becoming an alternative for the sustainable management of privately owned Protected Areas, whose results demonstrate diverse trends and practices being developed in these environments. With this research, it was verified that the RPPN uses a sustainable architecture in its facilities, and that the main reasons that led to its creation was the protection of local fauna and flora and ecological relevance of its location. It was noticed that the visitors seek to enjoy the nature that the region provides, besides the practices of ecotourism activities, promoting a contact with the local environment. Thus, it was found that the Catedral do Jalapão has sought through its practices to fulfill the socio-environmental role for which it was defined, being a model of sustainability and good practices associated with ecotourism. KEYWORDS: Protected Areas; Ecotourism; RPPN.
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