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Academic literature on the topic 'Eukaryotes'

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Published: 4 June 2021
Last updated: 6 July 2024

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Journal articles on the topic "Eukaryotes"

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Hofstatter, Paulo G., Alexander K. Tice, Seungho Kang, Matthew W. Brown, and Daniel J. G. Lahr. "Evolution of bacterial recombinase A ( recA ) in eukaryotes explained by addition of genomic data of key microbial lineages." Proceedings of the Royal Society B: Biological Sciences 283, no. 1840 (October 12, 2016): 20161453. http://dx.doi.org/10.1098/rspb.2016.1453.

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Recombinase enzymes promote DNA repair by homologous recombination. The genes that encode them are ancestral to life, occurring in all known dominions: viruses, Eubacteria, Archaea and Eukaryota. Bacterial recombinases are also present in viruses and eukaryotic groups (supergroups), presumably via ancestral events of lateral gene transfer. The eukaryotic recA genes have two distinct origins (mitochondrial and plastidial), whose acquisition by eukaryotes was possible via primary (bacteria–eukaryote) and/or secondary (eukaryote–eukaryote) endosymbiotic gene transfers (EGTs). Here we present a comprehensive phylogenetic analysis of the recA genealogy, with substantially increased taxonomic sampling in the bacteria, viruses, eukaryotes and a special focus on the key eukaryotic supergroup Amoebozoa, earlier represented only by Dictyostelium . We demonstrate that several major eukaryotic lineages have lost the bacterial recombinases (including Opisthokonta and Excavata), whereas others have retained them (Amoebozoa, Archaeplastida and the SAR-supergroups). When absent, the bacterial recA homologues may have been lost entirely (secondary loss of canonical mitochondria) or replaced by other eukaryotic recombinases. RecA proteins have a transit peptide for organellar import, where they act. The reconstruction of the RecA phylogeny with its EGT events presented here retells the intertwined evolutionary history of eukaryotes and bacteria, while further illuminating the events of endosymbiosis in eukaryotes by expanding the collection of widespread genes that provide insight to this deep history.
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Liapounova, Natalia A., Vladimir Hampl, Paul M. K. Gordon, Christoph W. Sensen, Lashitew Gedamu, and Joel B. Dacks. "Reconstructing the Mosaic Glycolytic Pathway of the Anaerobic Eukaryote Monocercomonoides." Eukaryotic Cell 5, no. 12 (October 27, 2006): 2138–46. http://dx.doi.org/10.1128/ec.00258-06.

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ABSTRACT All eukaryotes carry out glycolysis, interestingly, not all using the same enzymes. Anaerobic eukaryotes face the challenge of fewer molecules of ATP extracted per molecule of glucose due to their lack of a complete tricarboxylic acid cycle. This may have pressured anaerobic eukaryotes to acquire the more ATP-efficient alternative glycolytic enzymes, such as pyrophosphate-fructose 6-phosphate phosphotransferase and pyruvate orthophosphate dikinase, through lateral gene transfers from bacteria and other eukaryotes. Most studies of these enzymes in eukaryotes involve pathogenic anaerobes; Monocercomonoides, an oxymonad belonging to the eukaryotic supergroup Excavata, is a nonpathogenic anaerobe representing an evolutionarily and ecologically distinct sampling of an anaerobic glycolytic pathway. We sequenced cDNA encoding glycolytic enzymes from a previously established cDNA library of Monocercomonoides and analyzed the relationships of these enzymes to those from other organisms spanning the major groups of Eukaryota, Bacteria, and Archaea. We established that, firstly, Monocercomonoides possesses alternative versions of glycolytic enzymes: fructose-6-phosphate phosphotransferase, both pyruvate kinase and pyruvate orthophosphate dikinase, cofactor-independent phosphoglycerate mutase, and fructose-bisphosphate aldolase (class II, type B). Secondly, we found evidence for the monophyly of oxymonads, kinetoplastids, diplomonads, and parabasalids, the major representatives of the Excavata. We also found several prokaryote-to-eukaryote as well as eukaryote-to-eukaryote lateral gene transfers involving glycolytic enzymes from anaerobic eukaryotes, further suggesting that lateral gene transfer was an important factor in the evolution of this pathway for denizens of this environment.
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Porter, Susannah M., and Leigh Anne Riedman. "Frameworks for Interpreting the Early Fossil Record of Eukaryotes." Annual Review of Microbiology 77, no. 1 (September 15, 2023): 173–91. http://dx.doi.org/10.1146/annurev-micro-032421-113254.

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The origin of modern eukaryotes is one of the key transitions in life's history, and also one of the least understood. Although the fossil record provides the most direct view of this process, interpreting the fossils of early eukaryotes and eukaryote-grade organisms is not straightforward. We present two end-member models for the evolution of modern (i.e., crown) eukaryotes—one in which modern eukaryotes evolved early, and another in which they evolved late—and interpret key fossils within these frameworks, including where they might fit in eukaryote phylogeny and what they may tell us about the evolution of eukaryotic cell biology and ecology. Each model has different implications for understanding the rise of complex life on Earth, including different roles of Earth surface oxygenation, and makes different predictions that future paleontological studies can test.
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Field, Mark C., and Michael P. Rout. "Pore timing: the evolutionary origins of the nucleus and nuclear pore complex." F1000Research 8 (April 3, 2019): 369. http://dx.doi.org/10.12688/f1000research.16402.1.

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The name “eukaryote” is derived from Greek, meaning “true kernel”, and describes the domain of organisms whose cells have a nucleus. The nucleus is thus the defining feature of eukaryotes and distinguishes them from prokaryotes (Archaea and Bacteria), whose cells lack nuclei. Despite this, we discuss the intriguing possibility that organisms on the path from the first eukaryotic common ancestor to the last common ancestor of all eukaryotes did not possess a nucleus at all—at least not in a form we would recognize today—and that the nucleus in fact arrived relatively late in the evolution of eukaryotes. The clues to this alternative evolutionary path lie, most of all, in recent discoveries concerning the structure of the nuclear pore complex. We discuss the evidence for such a possibility and how this impacts our views of eukaryote origins and how eukaryotes have diversified subsequent to their last common ancestor.
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Zhao, Biying, and Feizhou Chen. "Genetic Diversity of Microbial Eukaryotes in the Pelagic and Littoral Zones of Lake Taihu, China." E3S Web of Conferences 118 (2019): 03039. http://dx.doi.org/10.1051/e3sconf/201911803039.

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Genetic diversity of microbial eukaryotes (0.8-20 μm) and its seasonal variation in the pelagic and littoral zones were investigated from in Meiliang Bay of Lake Taihu in China. The water samples were collected in four seasons (February, May, August, and November). The genetic diversity of microbial eukaryote was analyzed by terminal restriction fragment length polymorphism (T-RFLP) of PCR-amplified partial eukaryotic 18S rRNA fragments. T-RFLP indicated that the microbial eukaryotic community compositions differed between the pelagic and littoral zone, but the difference decreased in warm seasons. The main environmental factors which affected on the variations of microbial eukaryotic community compositions in pelagic and littoral zones were revealed by multivariate statistical analysis. The canonical correspondence analysis between the genetic diversity of microbial eukaryotes and environmental factors revealed the trophic status had the most important impact on the microbial eukaryotic communities. Besides, a strong top-down regulation of microbial eukaryotes by zooplanktons was found in summer.
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Porter, Susannah M., Heda Agić, and Leigh Anne Riedman. "Anoxic ecosystems and early eukaryotes." Emerging Topics in Life Sciences 2, no. 2 (July 13, 2018): 299–309. http://dx.doi.org/10.1042/etls20170162.

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Through much of the Proterozoic Eon (2.5–0.54 billion years ago, Ga), oceans were dominantly anoxic. It is often assumed that this put a brake on early eukaryote diversification because eukaryotes lived only in oxygenated habitats, which were restricted to surface waters and benthic environments near cyanobacterial mats. Studies of extant microbial eukaryotes show, however, that they are diverse and abundant in anoxic (including sulfidic) environments, often through partnerships with endo- and ectosymbiotic bacteria and archaea. Though the last common ancestor of extant eukaryotes was capable of aerobic respiration, we propose that at least some, and perhaps many, early eukaryotes were adapted to anoxic settings, and outline a way to test this with the microfossil and redox-proxy record in Proterozoic shales. This hypothesis might explain the mismatch between the record of eukaryotic body fossils, which extends back to >1.6 Ga, and the record of sterane biomarkers, which become diverse and abundant only after 659 Ma, as modern eukaryotes adapted to anoxic habitats do not make sterols (sterane precursors). In addition, an anoxic habitat might make sense for several long-ranging (>800 million years) and globally widespread eukaryotic taxa, which disappear in the late Neoproterozoic around the time oxic environments are thought to have become more widespread.
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Brueckner, Julia, and William F. Martin. "Bacterial Genes Outnumber Archaeal Genes in Eukaryotic Genomes." Genome Biology and Evolution 12, no. 4 (March 6, 2020): 282–92. http://dx.doi.org/10.1093/gbe/evaa047.

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Abstract Eukaryotes are typically depicted as descendants of archaea, but their genomes are evolutionary chimeras with genes stemming from archaea and bacteria. Which prokaryotic heritage predominates? Here, we have clustered 19,050,992 protein sequences from 5,443 bacteria and 212 archaea with 3,420,731 protein sequences from 150 eukaryotes spanning six eukaryotic supergroups. By downsampling, we obtain estimates for the bacterial and archaeal proportions. Eukaryotic genomes possess a bacterial majority of genes. On average, the majority of bacterial genes is 56% overall, 53% in eukaryotes that never possessed plastids, and 61% in photosynthetic eukaryotic lineages, where the cyanobacterial ancestor of plastids contributed additional genes to the eukaryotic lineage. Intracellular parasites, which undergo reductive evolution in adaptation to the nutrient rich environment of the cells that they infect, relinquish bacterial genes for metabolic processes. Such adaptive gene loss is most pronounced in the human parasite Encephalitozoon intestinalis with 86% archaeal and 14% bacterial derived genes. The most bacterial eukaryote genome sampled is rice, with 67% bacterial and 33% archaeal genes. The functional dichotomy, initially described for yeast, of archaeal genes being involved in genetic information processing and bacterial genes being involved in metabolic processes is conserved across all eukaryotic supergroups.
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Martin, William F., Sriram Garg, and Verena Zimorski. "Endosymbiotic theories for eukaryote origin." Philosophical Transactions of the Royal Society B: Biological Sciences 370, no. 1678 (September 26, 2015): 20140330. http://dx.doi.org/10.1098/rstb.2014.0330.

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For over 100 years, endosymbiotic theories have figured in thoughts about the differences between prokaryotic and eukaryotic cells. More than 20 different versions of endosymbiotic theory have been presented in the literature to explain the origin of eukaryotes and their mitochondria. Very few of those models account for eukaryotic anaerobes. The role of energy and the energetic constraints that prokaryotic cell organization placed on evolutionary innovation in cell history has recently come to bear on endosymbiotic theory. Only cells that possessed mitochondria had the bioenergetic means to attain eukaryotic cell complexity, which is why there are no true intermediates in the prokaryote-to-eukaryote transition. Current versions of endosymbiotic theory have it that the host was an archaeon (an archaebacterium), not a eukaryote. Hence the evolutionary history and biology of archaea increasingly comes to bear on eukaryotic origins, more than ever before. Here, we have compiled a survey of endosymbiotic theories for the origin of eukaryotes and mitochondria, and for the origin of the eukaryotic nucleus, summarizing the essentials of each and contrasting some of their predictions to the observations. A new aspect of endosymbiosis in eukaryote evolution comes into focus from these considerations: the host for the origin of plastids was a facultative anaerobe.
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Villarreal, Luis P., and Victor R. DeFilippis. "A Hypothesis for DNA Viruses as the Origin of Eukaryotic Replication Proteins." Journal of Virology 74, no. 15 (August 1, 2000): 7079–84. http://dx.doi.org/10.1128/jvi.74.15.7079-7084.2000.

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ABSTRACT The eukaryotic replicative DNA polymerases are similar to those of large DNA viruses of eukaryotic and bacterial T4 phages but not to those of eubacteria. We develop and examine the hypothesis that DNA virus replication proteins gave rise to those of eukaryotes during evolution. We chose the DNA polymerase from phycodnavirus (which infects microalgae) as the basis of this analysis, as it represents a virus of a primitive eukaryote. We show that it has significant similarity with replicative DNA polymerases of eukaryotes and certain of their large DNA viruses. Sequence alignment confirms this similarity and establishes the presence of highly conserved domains in the polymerase amino terminus. Subsequent reconstruction of a phylogenetic tree indicates that these algal viral DNA polymerases are near the root of the clade containing all eukaryotic DNA polymerase delta members but that this clade does not contain the polymerases of other DNA viruses. We consider arguments for the polarity of this relationship and present the hypothesis that the replication genes of DNA viruses gave rise to those of eukaryotes and not the reverse direction.
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Roger, Andrew J., and Laura A. Hug. "The origin and diversification of eukaryotes: problems with molecular phylogenetics and molecular clock estimation." Philosophical Transactions of the Royal Society B: Biological Sciences 361, no. 1470 (May 8, 2006): 1039–54. http://dx.doi.org/10.1098/rstb.2006.1845.

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Determining the relationships among and divergence times for the major eukaryotic lineages remains one of the most important and controversial outstanding problems in evolutionary biology. The sequencing and phylogenetic analyses of ribosomal RNA (rRNA) genes led to the first nearly comprehensive phylogenies of eukaryotes in the late 1980s, and supported a view where cellular complexity was acquired during the divergence of extant unicellular eukaryote lineages. More recently, however, refinements in analytical methods coupled with the availability of many additional genes for phylogenetic analysis showed that much of the deep structure of early rRNA trees was artefactual. Recent phylogenetic analyses of a multiple genes and the discovery of important molecular and ultrastructural phylogenetic characters have resolved eukaryotic diversity into six major hypothetical groups. Yet relationships among these groups remain poorly understood because of saturation of sequence changes on the billion-year time-scale, possible rapid radiations of major lineages, phylogenetic artefacts and endosymbiotic or lateral gene transfer among eukaryotes. Estimating the divergence dates between the major eukaryote lineages using molecular analyses is even more difficult than phylogenetic estimation. Error in such analyses comes from a myriad of sources including: (i) calibration fossil dates, (ii) the assumed phylogenetic tree, (iii) the nucleotide or amino acid substitution model, (iv) substitution number (branch length) estimates, (v) the model of how rates of evolution change over the tree, (vi) error inherent in the time estimates for a given model and (vii) how multiple gene data are treated. By reanalysing datasets from recently published molecular clock studies, we show that when errors from these various sources are properly accounted for, the confidence intervals on inferred dates can be very large. Furthermore, estimated dates of divergence vary hugely depending on the methods used and their assumptions. Accurate dating of divergence times among the major eukaryote lineages will require a robust tree of eukaryotes, a much richer Proterozoic fossil record of microbial eukaryotes assignable to extant groups for calibration, more sophisticated relaxed molecular clock methods and many more genes sampled from the full diversity of microbial eukaryotes.
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Dissertations / Theses on the topic "Eukaryotes"

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Clark, Francis. "A computational study of gene structure and splicing in model eukaryote organisms /." St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17395.pdf.

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Plass, Pórtulas Mireya 1982. "Comparative analysis of splicing in eukaryotes." Doctoral thesis, Universitat Pompeu Fabra, 2011. http://hdl.handle.net/10803/78124.

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L’splicing és el mecanisme pel qual els introns són eliminats del pre-mRNA per generar un trànscrit madur. Aquest procés és dut a terme per un complex macromolecular anomenat spliceosoma i requereix el reconeixement dels senyals d’splicing al pre-mRNA. Aquests senyals no són sempre identificats correctament, el que permet la producció de trànscrits diferents a partir d’un únic pre-mRNA mitjançant un procés anomenat splicing alternatiu. Aquest procés pot ser regulat mitjançant factors proteics específics o per altres mecanismes que alteren el reconeixement dels senyals d’splicing com l’estructura secundària adoptada pels pre-mRNAs. En aquesta tesi hem investigat els mecanismes de regulació de l’splicing en eucariotes mitjançant tècniques computacionals. També hem estudiat la relació existent entre les proteïnes que intervenen en la regulació de l’splicing i els senyals d’splicing, i com han coevolucionat en diferents espècies. Finalment, i tenint en compte les possibilitats que l’splicing alternatiu ofereix des del punt de vista evolutiu, també hem analitzat l’impacte de l’splicing alternatiu en l’evolució gènica.
Splicing is the mechanism by which introns are removed from the pre-mRNA to create a mature transcript. This process is performed by a macromolecular complex, the spliceosome, and involves the recognition of the splicing signals in the premRNA. These signals are not always perfectly recognized, which allows the production of different mature transcripts from a single pre-mRNA through a process called alternative splicing. This process can be regulated by specific protein factors or by other mechanisms that affect the recognition of the splicing signals, such as the secondary structure adopted by the pre-mRNA. In this thesis we have investigated the mechanisms of splicing regulation in eukaryotes using computational approaches. Moreover, we have also studied the relationship that exists between protein factors involved in splicing regulation and splicing signals, and how they have co-evolved across species. Finally, and considering the possibilities that alternative splicing can offer from the evolutionary point of view, he have also analyzed the impact of alternative splicing in gene evolution.
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van, Weringh Anna. "Exploring Codon-Anticodon Adaptation in Eukaryotes." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20303.

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tRNA genes have the fundamental role of translating the genetic code during protein synthesis. Beyond solely a passive decoding role, the tRNA pool exerts selection pressures on the codon usage of organisms and the viruses that infect them because processing codons read by rare tRNAs can be slow or even erroneous. To better understand the interactions of codons and anticodons in eukaryotic species, we first investigated whether tRNAs packaged into HIV-1 particles may relate to the poor codon usage of HIV-1 genes. By comparing the codon usage of HIV-1 genes with that of its human host, we found that tRNAs decoding poorly adapted codons are overrepresented in HIV-1 virions. Because the affinity of Gag-Pol for all tRNAs is non-specific, HIV packaging is most likely passive and reflects the tRNA pool at the time of viral particle formation. Moreover, differences that we found in the codon usage between early and late genes suggest alterations in the tRNA pool are induced late in viral infection. Next, we tested whether a reduced tRNA anticodon pattern, which was called into question by predicted tRNA datasets, is maintained across eukaryotes. tRNA prediction methods are prone to falsely identifying tRNA-derived repetitive sequences as functional tRNA genes. Thus, we proposed and tested a novel approach to identify falsely predicted tRNA genes using phylogenetics. Phylogenetic analysis removed nearly all the genes deviating from the anticodon pattern, therefore the anticodon pattern is reaffirmed across eukaryotes.
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Takamiya, Minako. "Endocrine disrupting chemical impacts on eukaryotes." Thesis, Cranfield University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487012.

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Endocrine Disrupting Chemicals (EDCs) are exogenous substances or mixtures that might lead to endocrine disruption in humans and wildlife. Bispheriol (BPA) was chosen as a model EDC and assessed for its toxic impacts on two eukaryotic test systems: (1) A fungal test system - white-rot basidiomycete, Trametes versicolor T. versicolor was tolerant of high concentrations of BPA (up to 300 ppm). The ligninolytic enzymes produced by the fungi were stimulated by 300 ppm of BPA. Of the three ligninolytic enzyme encoding genes examined, lignin peroxidase showed the greatest increase in expression in the presence ofBPA. (2) A mammalian test system - mouse Leydig tumor cell lines (mLTC-l) Time- and dose-responses of the cells stimulated with gonadotrophin to BPA demonstrated the clearest response in the expression of the steroidogenic genes without a marked effect on cell viability. The studies on the response of global gene expression to BPA by microarray analysis of mLTC-l cells showed 24 genes were differentially expressed in the presence of BPA (8 were increased and 16 were decreased). Several of these genes were related to steroid/cholesterol metabolism, transport and cell cycle regulation. In addition a study of male reproductive impairment was carried out to understand the reproductive toxicity of EDCs and likely effects on male infertility - one of the serious effects caused by EDCs. Human testicular tissues from fertile and infertile patients were examined by a microarray and 2642 genes were differentially expressed between the testes of fertile and infertile patients (955 genes were increased and 1687 genes were decreased in infertile patients). These genes are related to steroidogenesis, Leydig cell function, spermatid metamorphosis, cell cycle, and ribosome function. The array data exhibited phenotype-specific gene expression patterns. The most significant gene expression differences between fertile and infertile. patients were observed in spermatocyte- and spermatid- stages. Though further analysis is required, it is thought that BPA has weak modulatory impacts on eukaryotic test systems used in this study, however, its reproductive toxicity may not be negligible.
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Plass, Pórtulas Mireya. "Comparative analysis of splicing in eukaryotes." Doctoral thesis, Universitat Pompeu Fabra, 2011. http://hdl.handle.net/10803/78124.

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L’splicing és el mecanisme pel qual els introns són eliminats del pre-mRNA per generar un trànscrit madur. Aquest procés és dut a terme per un complex macromolecular anomenat spliceosoma i requereix el reconeixement dels senyals d’splicing al pre-mRNA. Aquests senyals no són sempre identificats correctament, el que permet la producció de trànscrits diferents a partir d’un únic pre-mRNA mitjançant un procés anomenat splicing alternatiu. Aquest procés pot ser regulat mitjançant factors proteics específics o per altres mecanismes que alteren el reconeixement dels senyals d’splicing com l’estructura secundària adoptada pels pre-mRNAs. En aquesta tesi hem investigat els mecanismes de regulació de l’splicing en eucariotes mitjançant tècniques computacionals. També hem estudiat la relació existent entre les proteïnes que intervenen en la regulació de l’splicing i els senyals d’splicing, i com han coevolucionat en diferents espècies. Finalment, i tenint en compte les possibilitats que l’splicing alternatiu ofereix des del punt de vista evolutiu, també hem analitzat l’impacte de l’splicing alternatiu en l’evolució gènica.
Splicing is the mechanism by which introns are removed from the pre-mRNA to create a mature transcript. This process is performed by a macromolecular complex, the spliceosome, and involves the recognition of the splicing signals in the premRNA. These signals are not always perfectly recognized, which allows the production of different mature transcripts from a single pre-mRNA through a process called alternative splicing. This process can be regulated by specific protein factors or by other mechanisms that affect the recognition of the splicing signals, such as the secondary structure adopted by the pre-mRNA. In this thesis we have investigated the mechanisms of splicing regulation in eukaryotes using computational approaches. Moreover, we have also studied the relationship that exists between protein factors involved in splicing regulation and splicing signals, and how they have co-evolved across species. Finally, and considering the possibilities that alternative splicing can offer from the evolutionary point of view, he have also analyzed the impact of alternative splicing in gene evolution.
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Coulombe-Huntington, Jasmin. "Intron loss and gain in Eukaryotes." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18747.

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Although introns were first discovered almost 30 years ago, their evolutionary origin and function remains elusive. In this thesis, I describe a referenced-based intron mapping method based on multi-species whole-genome alignments. We applied this method in two distinct studies. First we studied intron loss and gain dynamics in mammals and subsequently in Drosophila. We mapped known human introns onto the mouse, rat and dog genomes, mouse introns onto the human genome and Drosophila melanogaster introns onto 10 other fully sequenced Drosophila genomes. This genome-wide approach allowed us to assess the presence or absence of over 150,000 known human introns across four mammalian species and more than 35,000 D. melanogaster introns across 11 fruit fly species. We inferred 122 intron loss events in mammals and no intron gain events. In flies, we were able to identify 1754 intron loss events and 213 gain events. In both studies we found that lost introns tend to be extremely short and show higher than average similarity between their 5' splice-site sequence and the 3' partner splice-site sequence. We also demonstrate that losses in mammals occur preferentially in highly expressed house-keeping genes, while in Drosophila we show that lost and gained introns are flanked by longer than average exons, display quite distinct phase distributions and losses demonstrate significant clustering within genes. Across flies, it appears introns that have been lost evolve faster than other introns while they occur in slowly evolving genes. Our results in both studies strongly support the cDNA recombination mechanism of intron loss. The results in flies also suggest that selective pressures affect site-specific loss rates and show that intron gain has occurred within the Drosophila lineage, solidifying the “introns-middle” hypothesis and providing some hints about the gain mechanism and origin of introns.
Malgré le fait que les introns furent découverts il y a près de 30 ans, leur origine et leur fonction nous échappent encore. Au cours de cette thèse, je décrirais une méthode qui permet de projeter des introns d'une espèce de référence sur d'autres génomes, basée sur des alignements de génomes complets à plusieurs espèces. Nous avons appliqué cette méthode dans le cadre de deux études distinctes. Premièrement, nous avons étudié les pertes et les gains d'introns chez les mammifères et ensuite chez les Drosophiles. Nous avons projeté les introns humains sur le génome de la souris, du rat et du chien, les introns de la souris sur le génome humain et les introns de la Drosophile melanogaster sur les génomes de 10 autres espèces de Drosophiles complètement séquencées. Cette approche d'ordre génomique nous a permis de comparer la présence ou l'absence de plus de 150,000 introns humains dans quatre espèces de mammifères et plus de 35,000 introns de D. melanogaster dans 11 espèces de drosophiles. Nous avons détecté 122 pertes d'introns chez les mammifères mais aucun gain d'intron. Chez les mouches à fruits, nous avons identifié 1754 pertes d'introns et 213 gains d'introns. Dans les deux études, nous démontrons que les introns perdus sont extrêmement courts et démontrent une similarité relativement élevée entre le site d'épissage au début de l'intron et le site d'épissage à la fin de l'intron. Nous démontrons chez les mammifères les pertes d'introns se produisent de préférence dans des gènes hautement exprimés et de fonctions cruciales à la cellule. Chez les drosophiles nous démontrons que les introns perdus ou gagnés sont délimités par des exons plus longs que la moyenne, ont une distribution de phase plutôt distincte et les pertes démontrent une tendance à se retrouver en groupe à l'intérieur des gènes. Chez les mouches à fruits, il semble que les introns perdus évoluent plus rapidement que la moyenne
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Keeley, Anthony John. "Holliday junction processing enzymes in eukaryotes." Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313658.

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Fudenberg, Geoffrey. "Three-Dimensional Chromosome Organization in Eukaryotes." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17467516.

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The study of chromosome, and genome, organization is a both an ongoing challenge, and one with a long history. Following the advent of high-throughput sequencing and genomic technologies, much research has focused on the one-dimensional, or sequence-level, organization of genomes, with many successes. Nonetheless, genomes are physically organized as chromosomes in the three-dimensional confines of the cell nucleus, with implications for processes including gene regulation, DNA replication, and cell division. Recently, chromosome conformation capture (3C) based methods have enabled new high-resolution and genome-wide views (Hi-C) of chromosome organization in three-dimensions. 3C methods convert direct spatial contacts between pairs of genomic loci into molecular products that can be assayed using high-throughput sequencing. The new views of chromosomal organization enabled by 3C techniques have been the principal motivation for my graduate research. In particular, 3C technologies now pose multiple important computational and theoretical challenges, including how to: (1) process and filter large quantities of experimental data; (2) develop computational models of chromosomes that agree with and help the understanding of experimental data; and (3) integrate views from 3C technologies with other genomic datasets, including complementary characterizations of the chromatin fiber. This thesis presents a series of projects addressing these challenges in chronological order of their publication. The first project relates to the integration of views from Hi-C with other genomic datasets to understand the functional implications of chromosome organization. This project examined the connection between Hi-C chromosome contact maps and the distribution and positions of somatic copy number alterations observed across a variety of cancers. Since the observed alterations are the consequence of both mutational processes and evolutionary pressures on the cancers, we used a population genetics framework to consider how a mutational process governed by polymer physics might manifest in the patterns of alterations observed in cancer genomes. The second project relates to the processing and filtering of Hi-C data. This project investigated how to correct for various biases that could be introduced at different stages of the experimental protocol, and then how to decompose the resulting contact maps into dominant features of chromosomal organization. We found that we could dramatically compress the complexity of chromosome interaction patterns, and that these compressed patterns are surprisingly conserved between humans and mice. These methods have been used by our lab and others to investigate 3C data across a broad range of organisms. The third project involved the analysis of Hi-C data through the cell cycle, and the development of polymer models of chromosome organization in metaphase, when cells are prepared for division. Before cell division, chromosomes undergo extensive compaction; after division, they decondense and resume their cell-type-specific gene expression in interphase. We found that while interphase chromosome organization reflects cell-type-specific programs of gene expression, all traces of this organization are wiped clear in metaphase chromosomes. Our models of metaphase chromosomes allowed us to discriminate between two classic biological hypotheses of metaphase chromosome organization. We found that metaphase chromosomes are inconsistent with classic hierarchical models of folding, yet can be described by a two-stage process of compaction. The fourth project used polymer models to understand how local interactions, or loops, between genomic elements might in turn alter local chromosome organization. This has implications for gene regulation, as the classic model of eukaryotic gene expression requires direct spatial contact between a distal enhancer and a proximal promoter. We found that a chromatin loop can either suppress or facilitate enhancer-promoter interactions, depending on the location of the loop relative to the enhancer-promoter pair, and that looping interactions that do not directly involve an enhancer-promoter pair can nevertheless significantly modulate their interactions
Biophysics
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Akhtar, Mahmood Electrical Engineering &amp Telecommunications Faculty of Engineering UNSW. "Genomic sequence processing: gene finding in eukaryotes." Publisher:University of New South Wales. Electrical Engineering & Telecommunications, 2008. http://handle.unsw.edu.au/1959.4/40912.

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Of the many existing eukaryotic gene finding software programs, none are able to guarantee accurate identification of genomic protein coding regions and other biological signals central to pathway from DNA to the protein. Eukaryotic gene finding is difficult mainly due to noncontiguous and non-continuous nature of genes. Existing approaches are heavily dependent on the compositional statistics of the sequences they learn from and are not equally suitable for all types of sequences. This thesis firstly develops efficient digital signal processing-based methods for the identification of genomic protein coding regions, and then combines the optimum signal processing-based non-data-driven technique with an existing data-driven statistical method in a novel system demonstrating improved identification of acceptor splice sites. Most existing well-known DNA symbolic-to-numeric representations map the DNA information into three or four numerical sequences, potentially increasing the computational requirement of the sequence analyzer. Proposed mapping schemes, to be used for signal processing-based gene and exon prediction, incorporate DNA structural properties in the representation, in addition to reducing complexity in subsequent processing. A detailed comparison of all DNA representations, in terms of computational complexity and relative accuracy for the gene and exon prediction problem, reveals the newly proposed ?paired numeric? to be the best DNA representation. Existing signal processing-based techniques rely mostly on the period-3 behaviour of exons to obtain one dimensional gene and exon prediction features, and are not well equipped to capture the complementary properties of exonic / intronic regions and deal with the background noise in detection of exons at their nucleotide levels. These issues have been addressed in this thesis, by proposing six one-dimensional and three multi-dimensional signal processing-based gene and exon prediction features. All one-dimensional and multi-dimensional features have been evaluated using standard datasets such as Burset/Guigo1996, HMR195, and the GENSCAN test set. This is the first time that different gene and exon prediction features have been compared using substantial databases and using nucleotide-level metrics. Furthermore, the first investigation of the suitability of different window sizes for period-3 exon detection is performed. Finally, the optimum signal processing-based gene and exon prediction scheme from our evaluations is combined with a data-driven statistical technique for the recognition of acceptor splice sites. The proposed DSP-statistical hybrid is shown to achieve 43% reduction in false positives over WWAM, as used in GENSCAN.
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Ettwiller, Laurence Michele. "Computational investigations into cis-regulation in eukaryotes." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613876.

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Books on the topic "Eukaryotes"

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Esser, Karl, Ulrich Kück, Christine Lang-Hinrichs, Paul Lemke, Heinz Dieter Osiewacz, Ulf Stahl, and Paul Tudzynski. Plasmids of Eukaryotes. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82585-9.

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Hans, Trachsel, ed. Translation in eukaryotes. Boca Raton: CRC Press, 1991.

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Wingender, Edgar. Gene regulation in eukaryotes. Weinheim: VCH, 1993.

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Chatterjee, R. N., and Lucas Sánchez, eds. Genome Analysis in Eukaryotes. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/978-3-662-11829-0.

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1961-, Papavassiliou Athanasios, ed. Transcription factors in eukaryotes. Austin: Landes Bioscience, 1997.

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Wickner, Reed B., Alan Hinnebusch, Alan M. Lambowitz, I. C. Gunsalus, Alexander Hollaender, John R. Preer, Laurens Mets, Richard I. Gumport, Claire M. Wilson, and Gregory Kuny, eds. Extrachromosomal Elements in Lower Eukaryotes. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4684-5251-8.

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David, Beach, Basilico Claudio, Newport John, and Cold Spring Harbor Laboratory, eds. Cell cycle control in eukaryotes. Cold Spring Harbor, N.Y: Cold Spring Harbor Laboratory, 1988.

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1937-, Koltin Yigal, and Leibowitz Michael J. 1945-, eds. Viruses of fungi and simple eukaryotes. New York: M. Dekker, 1988.

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1924-, Esser Karl, ed. Plasmids of eukaryotes: Fundamentals and applications. Berlin: Springer-Verlag, 1986.

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Villa, Tomás González, and Trinidad de Miguel Bouzas, eds. Developmental Biology in Prokaryotes and Lower Eukaryotes. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-77595-7.

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Book chapters on the topic "Eukaryotes"

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Ligrone, Roberto. "Eukaryotes." In Biological Innovations that Built the World, 155–231. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-16057-9_6.

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Gooch, Jan W. "Eukaryotes." In Encyclopedic Dictionary of Polymers, 891. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_13705.

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Blanchet, Sandra, and Namit Ranjan. "Translation Phases in Eukaryotes." In Ribosome Biogenesis, 217–28. New York, NY: Springer US, 2022. http://dx.doi.org/10.1007/978-1-0716-2501-9_13.

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AbstractProtein synthesis in eukaryotes is carried out by 80S ribosomes with the help of many specific translation factors. Translation comprises four major steps: initiation, elongation, termination, and ribosome recycling. In this review, we provide a comprehensive list of translation factors required for protein synthesis in yeast and higher eukaryotes and summarize the mechanisms of each individual phase of eukaryotic translation.
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Rizzotti, Martino. "Eukaryotes: Dictyosomes." In Early Evolution, 104–8. Basel: Birkhäuser Basel, 2000. http://dx.doi.org/10.1007/978-3-0348-8668-0_8.

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Yokobori, Shin-ichi, and Ryutaro Furukawa. "Eukaryotes Appearing." In Astrobiology, 105–21. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-3639-3_8.

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Fenchel, Tom. "Anaerobic Eukaryotes." In Cellular Origin, Life in Extreme Habitats and Astrobiology, 3–16. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-1896-8_1.

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Rizzotti, Martino. "Eukaryotes: Plastidial Symbioses." In Early Evolution, 122–35. Basel: Birkhäuser Basel, 2000. http://dx.doi.org/10.1007/978-3-0348-8668-0_10.

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Rizzotti, Martino. "Eukaryotes: The Cilium." In Early Evolution, 136–54. Basel: Birkhäuser Basel, 2000. http://dx.doi.org/10.1007/978-3-0348-8668-0_11.

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Romani, Andrea M. P. "Magnesium in Eukaryotes." In Encyclopedia of Metalloproteins, 1255–64. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-1533-6_260.

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Reitner, Joachim. "Early Precambrian Eukaryotes." In Encyclopedia of Geobiology, 341–42. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-1-4020-9212-1_168.

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Conference papers on the topic "Eukaryotes"

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Nettersheim, Benjamin, and Jochen Brocks. "Primordial Eukaryotes in a Paleoproterozoic Sea." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.1911.

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Zhang, S., S. Ma, J. Su, H. Wang, and X. Wang. "Underestimated Ecological Contribution of Mesoproterozoic Eukaryotes." In IMOG 2023. European Association of Geoscientists & Engineers, 2023. http://dx.doi.org/10.3997/2214-4609.202333134.

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Cao, Chen, Xueying Xie, and Zuhong Lu. "Evolutionary Implications of Protein Domain Network in Eukaryotes." In 2010 4th International Conference on Bioinformatics and Biomedical Engineering (iCBBE). IEEE, 2010. http://dx.doi.org/10.1109/icbbe.2010.5516602.

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Zhang, Feifei, Noah J. Planavsky, Richard Stockey, Shuhai Xiao, Shuzhong Shen, Ying Cui, and A. D. Anbar. "SHALLOW WATER ANOXIA PRECEDING THE RISE OF EUKARYOTES." In GSA 2020 Connects Online. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020am-355564.

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Premalatha, C., Chandrabose Aravindan, and K. Kannan. "Promoter prediction in eukaryotes using soft computing techniques." In 2011 IEEE Recent Advances in Intelligent Computational Systems (RAICS). IEEE, 2011. http://dx.doi.org/10.1109/raics.2011.6069368.

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Cohen, Phoebe, and Robin Kodner. "EUKARYOTES WERE LIKELY AEROBIC AND ESTABLISHED IN PROTEROZOIC ECOSYSTEMS." In GSA Connects 2021 in Portland, Oregon. Geological Society of America, 2021. http://dx.doi.org/10.1130/abs/2021am-369878.

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"Bacteriophages as vectors of gene transfer from prokaryotes to eukaryotes." In Bioinformatics of Genome Regulation and Structure/Systems Biology (BGRS/SB-2022) :. Institute of Cytology and Genetics, the Siberian Branch of the Russian Academy of Sciences, 2022. http://dx.doi.org/10.18699/sbb-2022-074.

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Porter, Susannah, John L. Moore, and Leigh Anne Riedman. "PATTERNS IN THE EVOLUTIONARY ACQUISITIONS OF MINERALIZED SKELETONS IN EUKARYOTES." In GSA Connects 2021 in Portland, Oregon. Geological Society of America, 2021. http://dx.doi.org/10.1130/abs/2021am-370950.

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Akhtar, Mahmood, Julien Epps, and Eliathamby Ambikairajah. "Paired Spectral Content Measure for Gene and Exon Prediction in Eukaryotes." In 2007 International Conference on Information and Emerging Technologies. IEEE, 2007. http://dx.doi.org/10.1109/iciet.2007.4381323.

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Bishop, Caleb, Grant Cox, Marcus Kunzmann, April Shannon, Morgan Blades, Jochen Brocks, Alan Collins, and David Giles. "Linking Neoproterozoic Oxygenation to the Marinoan Glaciation and Radiation of Eukaryotes." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.197.

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Reports on the topic "Eukaryotes"

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Scott, Kenneth L., and Sharon E. Plon. Alternative DNA Damage Checkpoint Pathways in Eukaryotes. Fort Belvoir, VA: Defense Technical Information Center, April 2001. http://dx.doi.org/10.21236/ada396714.

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Li, Yi-Chen J. Alternative DNA Damage Checkpoint Pathways in Eukaryotes. Fort Belvoir, VA: Defense Technical Information Center, April 1999. http://dx.doi.org/10.21236/ada369305.

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Li, Yi-Chen. Alternative DNA Damage Checkpoint Pathways in Eukaryotes. Fort Belvoir, VA: Defense Technical Information Center, April 2000. http://dx.doi.org/10.21236/ada381190.

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Alatalo, Philip, Rebecca J. Gast,, and Ann M. Tarrant. Final cruise report and post-cruise sample processing R/V Gulf Challenger “GC Mixo 23-01”. Woods Hole Oceanographic Institution, November 2023. http://dx.doi.org/10.1575/1912/67231.

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A primary topic of interest in the field of biological oceanography is the role of planktonic productivity in the global carbon cycle. Over the past 20+ years, the traditional food web of algal production, zooplanktonic consumers and higher trophic level predators has been undergoing revision with a stronger understanding of the contributions made within the microbial loop. Of particular interest has been mixotrophy, the blurring of trophic mode assignments within the microbial eukaryotes. The overall goal of this cruise was to obtain a snapshot of the prevalence of mixotrophy within the Gulf of Maine and the potential contributions of mixotrophs to copepod diets. We proposed to accomplish this goal by sampling water and zooplankton from 3 stations.
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Alatalo, Philip, Rebecca J. Gast, Ann M. Tarrant, Rodrigo Zuñiga, and Cameron Johnson. Final cruise report and post-cruise sample processing R/V Gulf Challenger “GC Mixo 23-03”. Woods Hole Oceanographic Institution, November 2023. http://dx.doi.org/10.1575/1912/67240.

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A primary topic of interest in the field of biological oceanography is the role of planktonic productivity in the global carbon cycle. Over the past 20+ years, the traditional food web of algal production, zooplanktonic consumers and higher trophic level predators has been undergoing revision with a stronger understanding of the contributions made within the microbial loop. Of particular interest has been mixotrophy, the blurring of trophic mode assignments within the microbial eukaryotes. The overall goal of this cruise was to obtain a snapshot of the prevalence of mixotrophy within the Gulf of Maine and the potential contributions of mixotrophs to copepod diets. We proposed to accomplish this goal by sampling water and zooplankton from 3 stations.
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Alatalo, Philip, Rebecca J. Gast, Ann M. Tarrant, and Rodrigo Zuñiga. Final cruise report and post-cruise sample processing R/V Gulf Challenger “GC Mixo 23-04”. Woods Hole Oceanographic Institution, November 2023. http://dx.doi.org/10.1575/1912/67241.

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A primary topic of interest in the field of biological oceanography is the role of planktonic productivity in the global carbon cycle. Over the past 20+ years, the traditional food web of algal production, zooplanktonic consumers and higher trophic level predators has been undergoing revision with a stronger understanding of the contributions made within the microbial loop. Of particular interest has been mixotrophy, the blurring of trophic mode assignments within the microbial eukaryotes. The overall goal of this cruise was to obtain a snapshot of the prevalence of mixotrophy within the Gulf of Maine and the potential contributions of mixotrophs to copepod diets. This cruise was meant to supplement the previous cruise (2303) during which we were only able to sample one station (WB7). The specific goal for this cruise was to sample WB2.
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Schuster, Gadi, and David Stern. Integrated Studies of Chloroplast Ribonucleases. United States Department of Agriculture, September 2011. http://dx.doi.org/10.32747/2011.7697125.bard.

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Gene regulation at the RNA level encompasses multiple mechanisms in prokaryotes and eukaryotes, including splicing, editing, endo- and exonucleolytic cleavage, and various phenomena related to small or interfering RNAs. Ribonucleases are key players in nearly all of these post-transcriptional mechanisms, as the catalytic agents. This proposal continued BARD-funded research into ribonuclease activities in the chloroplast, where RNase mutation or deficiency can cause metabolic defects and is often associated with plant chlorosis, embryo or seedling lethality, and/or failure to tolerate nutrient stress. The first objective of this proposal was to examined a series of point mutations in the PNPase enzyme of Arabidopsis both in vivo and in vitro. This goal is related to structure-function analysis of an enzyme whose importance in many cellular processes in prokaryotes and eukaryotes has only begun to be uncovered. PNPase substrates are mostly generated by endonucleolytic cleavages for which the catalytic enzymes remain poorly described. The second objective of the proposal was to examine two candidate enzymes, RNase E and RNase J. RNase E is well-described in bacteria but its function in plants was still unknown. We hypothesized it catalyzes endonucleolytic cleavages in both RNA maturation and decay. RNase J was recently discovered in bacteria but like RNase E, its function in plants had yet to be explored. The results of this work are described in the scientific manuscripts attached to this report. We have completed the first objective of characterizing in detail TILLING mutants of PNPase Arabidopsis plants and in parallel introducing the same amino acids changes in the protein and characterize the properties of the modified proteins in vitro. This study defined the roles for both RNase PH core domains in polyadenylation, RNA 3’-end maturation and intron degradation. The results are described in the collaborative scientific manuscript (Germain et al 2011). The second part of the project aimed at the characterization of the two endoribonucleases, RNase E and RNase J, also in this case, in vivo and in vitro. Our results described the limited role of RNase E as compared to the pronounced one of RNase J in the elimination of antisense transcripts in the chloroplast (Schein et al 2008; Sharwood et al 2011). In addition, we characterized polyadenylation in the chloroplast of the green alga Chlamydomonas reinhardtii, and in Arabidopsis (Zimmer et al 2009). Our long term collaboration enabling in vivo and in vitro analysis, capturing the expertise of the two collaborating laboratories, has resulted in a biologically significant correlation of biochemical and in planta results for conserved and indispensable ribonucleases. These new insights into chloroplast gene regulation will ultimately support plant improvement for agriculture.
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Chamovitz, Daniel, and Albrecht Von Arnim. Translational regulation and light signal transduction in plants: the link between eIF3 and the COP9 signalosome. United States Department of Agriculture, November 2006. http://dx.doi.org/10.32747/2006.7696515.bard.

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The COP9 signalosome (CSN) is an eight-subunit protein complex that is highly conserved among eukaryotes. Genetic analysis of the signalosome in the plant model species Arabidopsis thaliana has shown that the signalosome is a repressor of light dependent seedling development as mutant Arabidopsis seedlings that lack this complex develop in complete darkness as if exposed to light. These mutant plants die following the seedling stage, even when exposed to light, indicating that the COP9 signalosome also has a central role in the regulation of normal photomorphogenic development. The biochemical mode of action of the signalosome and its position in eukaryotic cell signaling pathways is a matter of controversy and ongoing investigation, and recent results place the CSN at the juncture of kinase signaling pathways and ubiquitin-mediated protein degradation. We have shown that one of the many CSN functions may relate to the regulation of translation through the interaction of the CSN with its related complex, eukaryotic initiation factor (eIF3). While we have established a physical connection between eIF3 subunits and CSN subunits, the physiological and developmental significance of this interaction is still unknown. In an effort to understand the biochemical activity of the signalosome, and its role in regulating translation, we originally proposed to dissect the contribution of "h" subunit of eIF3 (eIF3h) along the following specific aims: (i) Isolation and phenotypic characterization of an Arabidopsis loss-of-function allele for eIF3h from insertional mutagenesis libraries; (ii) Creation of designed gain and loss of function alleles for eIF3h on the basis of its nucleocytoplasmic distribution and its yeast-two-hybrid interactions with other eIF3 and signalosome partner proteins; (iii) Determining the contribution of eIF3h and its interaction with the signalosome by expressing specific mutants of eIF3h in the eIF3h- loss-of function background. During the course of the research, these goals were modified to include examining the genetic interaction between csn and eif3h mutations. More importantly, we extended our effort toward the genetic analysis of mutations in the eIF3e subunit, which also interacts with the CSN. Through the course of this research program we have made several critical scientific discoveries, all concerned with the apparent diametrically opposed roles of eIF3h and eIF3e. We showed that: 1) While eIF3e is essential for growth and development, eIF3h is not essential for growth or basal translation; 2) While eIF3e has a negative role in translational regulation, eIF3h is positively required for efficient translation of transcripts with complex 5' UTR sequences; 3) Over-accumulation of eIF3e and loss-of-function of eIF3h both lead to cop phenotypes in dark-grown seedlings. These results were published in one publication (Kim et al., Plant Cell 2004) and in a second manuscript currently in revision for Embo J. Are results have led to a paradigm shift in translation research – eIF3 is now viewed in all systems as a dynamic entity that contains regulatory subuits that affect translational efficiency. In the long-term agronomic outlook, the proposed research has implications that may be far reaching. Many important plant processes, including developmental and physiological responses to light, abiotic stress, photosynthate, and hormones operate in part by modulating protein translation [23, 24, 40, 75]. Translational regulation is slowly coming of age as a mechanism for regulating foreign gene expression in plants, beginning with translational enhancers [84, 85] and more recently, coordinating the expression of multiple transgenes using internal ribosome entry sites. Our contribution to understanding the molecular mode of action of a protein complex as fundamental as eIF3 is likely to lead to advances that will be applicable in the foreseeable future.
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Cavanaugh, Colleen M. Molecular Characterization and Regulation of Ammonia Assimilation in Chemoautotrophic Prokaryote-Eukaryote Symbioses. Fort Belvoir, VA: Defense Technical Information Center, July 1998. http://dx.doi.org/10.21236/ada350743.

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Cooper, Priscilla. Prokaryotic and eukaryotic cell-free systems for prototyping: CRADA Final Report. Office of Scientific and Technical Information (OSTI), October 2022. http://dx.doi.org/10.2172/1890450.

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