Artykuły w czasopismach na temat „Northern hybridisation analysis”
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Tran, Nham. "Fast and Simple microRNA Northern Blots". Biochemistry Insights 2 (styczeń 2009): BCI.S2257. http://dx.doi.org/10.4137/bci.s2257.
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RNA northern blots provide robust measurements of gene expression. The simple northern blot technique described in this report has been optimised to provide rapid, reproducible detection and analysis of mature and precursor forms of microRNAs. This protocol economises on the use of commercially available components and secondly reduces the hybridisation step to 2 hours.
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Scotti, Ivan, Anna Mariani, Valentino Verona, Alberto Candolini, Carlo A. Cenci i Angelo M. Olivieri. "AFLP markers and cytotaxonomic analysis reveal hybridisation in the genus Schoenus (Cyperaceae)". Genome 45, nr 2 (1.04.2002): 222–28. http://dx.doi.org/10.1139/g01-138.
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Molecular, cytological, and morphological data support the existence of a hybrid population between Schoenus nigricans and Schoenus ferrugineus. This population was found in northeastern Italy, where S. nigricans is central with respect to its natural range and S. ferrugineus is marginal, being most common in the Alps and in central and northern Europe. Molecular marker data show that the putative hybrid population is genetically intermediate between nearby populations of the parent species. Cytological evidence confirmed the hybrid nature of this population, as does the almost complete sterility of plants within the population. Although no seeds were produced by the hybrid population, some possibly fertile pollen grains were produced; this suggests that the possibility of introgression between the two species through the hybrids cannot completely be excluded.Key words: Schoenus, AFLP markers, chromosome behaviour, introgression.
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Vanmontfort, D., AE Fidler, DA Heath, SB Lawrence, DJ Tisdall, PJ Greenwood i KP McNatty. "cDNA sequence analysis, gene expression and protein localisation of the inhibin alpha-subunit of Australian brushtail possum (Trichosurus vulpecula)". Journal of Molecular Endocrinology 21, nr 2 (1.10.1998): 141–52. http://dx.doi.org/10.1677/jme.0.0210141.
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An inhibin alpha-subunit cDNA sequence from the Australian brushtail possum (Trichosurus vulpecula) has been identified and analysed. The cDNA includes an open reading frame encoding a predicted precursor protein of 361 amino acids. The predicted protein sequence includes four possible proteolytic cleavage sites, 12 evolutionarily conserved cysteine residues and three potential N-linked glycosylation sites. The mature alpha-subunit is the carboxyl terminal fragment (alphaC) consisting of 131 amino acids. The full-length precursor protein shows a mean identity with eutherian homologues of 69.8%. The homology is not evenly distributed, with the putative alphaC fragment showing the highest level (79.7%). Using Northern hybridisation, an alpha-subunit transcript of approximately 1.6 kb was detected in adult possum ovary. Using in situ hybridisation and immunocytochemistry, inhibin alpha-subunit was localised exclusively to the granulosa cell layers of follicles. Hybridisation and immunostaining for the inhibin alpha-subunit were first observed in granulosa cells of primary follicles and the expression continued throughout all stages of follicular growth. Inhibin alpha-subunit mRNA and protein were also detected in cells of the corpus luteum. In summary, results indicate considerable conservation of the structure and possible function of the inhibin alpha-subunit protein since the divergence of the marsupial and eutherian mammalian lineages. The expression data suggest that, in the adult possum, inhibin may have a role in ovarian follicular growth from the primary stage of development.
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Ruiz-Medrano, Roberto, Jesús Hinojosa Moya, Beatriz Xoconostle-Cázares i William J. Lucas. "Influence of cucumber mosaic virus infection on the mRNA population present in the phloem translocation stream of pumpkin plants". Functional Plant Biology 34, nr 4 (2007): 292. http://dx.doi.org/10.1071/fp06300.
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The effect of cucumber mosaic virus (CMV) infection on the phloem sap mRNA population was investigated in pumpkin Cucurbita maxima Duch. cv. Big Max, through analysis of a suppressive subtractive hybridisation (SSH) library. Analysis of the infected phloem library identified 91 highly diverse mRNA species, including enzymes involved in general metabolism, transcription factors and signalling agents. Our analysis indicated that, quantitatively, the effect of CMV infection on the composition of the phloem sap transcriptome was minor in nature. Virtual northern analysis was used to confirm the specific upregulation of these transcripts in the phloem of CMV-infected plants. In silico northern analysis also confirmed that none of the transcripts identified in the SSH library was contained in the population of mRNA species present in the phloem sap of healthy plants. Induction levels ranged from low to high and in situ hybridisation studies showed that transcripts displayed a range of accumulation patterns. Collectively, our findings suggest that plants have evolved a highly robust mechanism for the exchange of information macromolecules between the companion cell (CC) and the sieve tube system. Production of viral movement protein (MP) in the CC is not sufficient for the indiscriminate transport of mRNA into the sieve element. Our findings are discussed in the context of symptom development and likely strong selection pressure, on the viral genome, to encode for a MP that does not adversely interfere with the phloem long-distance trafficking system.
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Wang, Zeng-Yu, i Yaxin Ge. "Rapid and efficient production of transgenic bermudagrass and creeping bentgrass bypassing the callus formation phase". Functional Plant Biology 32, nr 9 (2005): 769. http://dx.doi.org/10.1071/fp05083.
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Callus culture has been an inevitable step in genetic transformation of monocotyledonous (monocot) species. The induction and maintenance of embryogenic calluses is time-consuming, laborious and also requires experience. A straightforward and callus-free transformation procedure was developed and demonstrated for two monocot species, bermudagrass (Cynodon spp.) and creeping bentgrass (Agrostis stolonifera). Stolon nodes were infected and co-cultivated with Agrobacterium tumefaciens harboring pCAMBIA or pTOK233 binary vectors. Green shoots were directly produced from infected stolon nodes 4–5 weeks after hygromycin selection. Without callus formation and with minimum tissue culture, this procedure allowed us to obtain well-rooted transgenic plantlets in only 7 weeks and greenhouse-grown plants in only 9 weeks. The established plants were screened by PCR; the transgenic nature of the plants was demonstrated by Southern hybridisation analysis. Expression of the transgenes was confirmed by northern hybridisation analysis and GUS staining. Based on the number of transgenic plants obtained and the number of stolon nodes inoculated, transformation frequencies of 4.8%–6.1% and 6.3%–11.3% were achieved for bermudagrass and creeping bentgrass, respectively. The rapid and efficient production of transgenic plants without callus induction is a significant improvement for genetic transformation of monocot species.
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Lloyd, Andrew, Gavin Dixon, Xu Feng Huang, Phillip Ward, Stan Catts, Ian Hickie i Denis Wakefield. "Molecular Biology and the Major Psychoses". Australian & New Zealand Journal of Psychiatry 31, nr 1 (luty 1997): 12–16. http://dx.doi.org/10.3109/00048679709073794.
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Objective:To highlight the potential role of molecular biological studies in examining the expression of genes of interest in brain tissue to elucidate the pathophysiological basis of the major psychoses. Method:To review the principles underlying the available techniques for expression studies. Results:Detection of messenger RNA by in situ hybridisation and quantitation by Northern analysis are powerful tools to detect abnormalities in gene expression in brain tissue. Conclusion:The availability of simple techniques to examine the expression of RNA and protein products of individual genes, including examination at the level of individual cells, offers a clear opportunity to define the molecular basis of the major psychoses.
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Albach, Dirk C., i Barbara G. Briggs. "Phylogenetic analysis of Australian species of Veronica (V. section Labiatoides; Plantaginaceae)". Australian Systematic Botany 25, nr 5 (2012): 353. http://dx.doi.org/10.1071/sb12014.
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Phylogenetic analyses of DNA-sequence data have revealed that the southern hemisphere species of Veronica are derived from within the northern hemisphere Veronica clade. Previous analyses focussed on the species in New Zealand and included at maximum 7 of 23 species of section Labiatoides from Australia. In the present study, we used nuclear ribosomal-ITS and plastid ndhF–rpl32-spacer sequence data of all species currently recognised in Australia to analyse phylogenetic patterns. Most importantly, herbaceous species from coastal calcareous sands or limestone habitats do not form a clade with those from shady, moist forest habitats, as formerly believed, but seem to be independently derived from woody species. Incongruence between results from nuclear- and plastid-DNA markers suggest hybridisation to be an important factor in the evolution of the group. Our sample of V. parnkalliana included alleles similar to V. decorosa and V. novae-hollandiae at both loci, which suggests a hybrid origin.
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Farquharson, M. A., R. Harvie, A. Kennedy i A. M. McNicol. "Detection of mRNA by in situ hybridisation and in northern blot analysis using oligodeoxynucleotide probes labelled with alkaline phosphatase." Journal of Clinical Pathology 45, nr 11 (1.11.1992): 999–1002. http://dx.doi.org/10.1136/jcp.45.11.999.
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Friess, H., Z. Lu, H. U. Graber, A. Zimmermann, G. Adler, M. Korc, R. M. Schmid i M. W. Büchler. "bax, but notbcl-2, influences the prognosis of human pancreatic cancer". Gut 43, nr 3 (1.09.1998): 414–21. http://dx.doi.org/10.1136/gut.43.3.414.
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Background—bcl-2and bax belong to thebcl-2-related gene family, which marks a new class of genes that influence apoptosis. Thebcl-2 oncogene acts as a broad antiapoptotic factor and extends both normal and tumour cell survival. In contrast, the bax gene is a promoter of apoptosis.Aims—To analyse the expression of bcl-2 andbax in pancreatic cancer and correlate the results with clinical parameters.Patients—Pancreatic cancer tissue samples were obtained from 28 female and 32 male patients (median age 63, range 43–79 years) having surgery for pancreatic cancer. Normal pancreatic tissues obtained from 18 previously healthy organ donors served as controls.Methods—The levels ofbcl-2 and baxmRNA expression were analysed by northern blot and the exact site of mRNA transcription was determined by in situ hybridisation. The presence of the corresponding proteins was determined by immunohistochemistry.Results—Northern blot analysis indicated that, in comparison with the normal pancreas,bcl-2 mRNA was overexpressed in 30% andbax mRNA in 61% of the pancreatic cancer samples. Concomitant overexpression ofbcl-2 and bax was present in 26% of the cancer samples. Pancreatic adenocarcinomas exhibited 3.7-fold and 5.4-fold increases (p<0.001) inbcl-2 and baxmRNA levels respectively. In situ hybridisation showed that bothbcl-2 and baxmRNA were expressed in the cancer cells. Immunohistochemical analysis showed positive Bcl-2 and Bax immunostaining in 28 and 83% of the cancer samples respectively. In multivariate analysis (Cox regression model), bax expression was found to be a strong indicator of survival (p<0.001). Patients whose tumours exhibited Bax immunostaining lived significantly longer (12 months) than those whose tumours were Bax negative (five months) (p<0.039). In contrast, no relation was found between Bcl-2 and survival time.Conclusions—The data indicate that genes that are involved in the regulation of apoptosis are upregulated in human pancreatic cancer cells. Prolonged survival times in patients in whom apoptosis promoting factors are upregulated indicate that apoptotic pathways are of biological significance in pancreatic cancer.
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Zanella, Lorenzo. "Biodiversity of the endangered coastal beetle Scarites laevigatus: is the northern Adriatic population a geographical subspecies or a case of introgressive hybridisation? (Coleoptera: Carabidae)". Fragmenta Entomologica 50, nr 2 (21.12.2018): 149–60. http://dx.doi.org/10.4081/fe.2018.274.
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The ground beetle Scarites laevigatus Fabricius, 1792 is a specialized predator occurring in the Mediterranean sandy shores, currently threatened with disappearance due to the widespread modification of beach ecosystems. The present study purposes a morphological analysis of the northern Adriatic form, described by Puel in 1938 as a subspecies with the name venetianus, in comparison with the typical form of this taxon and S. terricola. The examination of pronotum, elytra, body shape, male genitalia and wing development, suggests that the studied population is different from the nominotypical form and might originate from the introgressive hybridisation of S. terricola with the north Adriatic populations of S. laevigatus. This hypothesis is discussed in the light of current knowledge of the systematics and ecology of the putative parent species.
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Pryor, LD, ER Williams i BV Gunn. "A morphometric analysis of Eucalyptus urophylla and related taxa with descriptions of two new species". Australian Systematic Botany 8, nr 1 (1995): 57. http://dx.doi.org/10.1071/sb9950057.
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Over 400 specimens from 26 locations, mainly in the Lesser Sunda Islands and some from New Guinea and northern Cape York, were examined. These were representative of an array of forms ordinarily assigned to Eucalyptus urophylla, E. pellita and an undescribed species as well as those considered by some to be hybrid between E. alba and E. urophylla. The latter has long been considered to show considerable polymorphism. Re-examination of the available material and records suggest that interspecific hybridisation is not significantly involved in this variability. Although this examination pointed to the existence of some differentiation at the level of species in this array, there was still a core of material which could not be separated readily into subgroups. Measurements were taken of selected floral and foliar morphological features which were then subject to statistical analysis to ascertain if subgroups were discernible on this basis. As a result, the separation of two species, Eucalyptus orophila sp. nov. and Eucalyptus wetarensis sp. nov. from Eucalyptus urophylla sensu lato in the Lesser Sunda Islands, is supported. The related populations called species A by Pinyopusarerk et al. (1993), from New Guinea and northern Cape York, were to a somewhat lesser extent separated on these criteria. These results were paralleled by evidence from seedling morphology and oil characteristics. Isozyme analysis gave a similar grouping for the material from Wetar, but did not indicate other separations from the core E. urophylla.
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Maguire, S. M., M. R. Millar, R. M. Sharpe, J. Gaughan i P. T. K. Saunders. "Investigation of the potential role of the germ cell complement in control of the expression of transferrin mRNA in the prepubertal and adult rat testis". Journal of Molecular Endocrinology 19, nr 1 (sierpień 1997): 67–77. http://dx.doi.org/10.1677/jme.0.0190067.
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ABSTRACT Iron is required for the normal development of germ cells during spermatogenesis. Because these cells have no direct access to systemic iron, there exists a shuttle system involving production and secretion of the iron-transporting protein transferrin by the Sertoli cells. Previous reports using cultures of immature Sertoli cells exposed to adult germ cells, or in vivo studies involving germ cell-depleted adult rat testes, concluded that production of transferrin by Sertoli cells is modulated by germ cell complement. In the present study we have used in situ hybridisation with cRNA probes directed against the 5′ and 3′ ends of transferrin mRNA to examine the pattern of expression of transferrin in the immature and adult rat testis. Adult rats were treated with ethane dimethane sulphonate or methoxyacetic acid (MAA) to manipulate their testosterone levels or germ cell complement respectively. Initial findings obtained using the 3′ probe showed a decrease in transferrin mRNA associated with round spermatid depletion. However, these data were not confirmed by in situ hybridisation when the 5′ probe was used. The specificity of the probes was examined using Northern blotting and the 3′ probe was found to hybridise to the germ cell transcript for hemiferrin even under conditions of high stringency. Examination of immature and pubertal rat testes by in situ hybridisation using the 5′ transferrin-specific probe found that as early as 14 days of age the level of expression of transferrin mRNA was clearly different between tubules, and the mRNA appeared to be expressed in Leydig cells on and after day 31. In the adult rat testis, maximal expression of transferrin mRNA was found at stages VIII-XIV, calling into question the interpretation of the results of some previous studies showing expression of transferrin mRNA at all stages of the spermatogenic cycle. This stage-specific pattern of expression was not altered by acute germ cell depletion using MAA. However, Northern blot analysis showed a statistically significant increase in transferrin mRNA expression at 7 days after MAA treatment when pachytene spermatocytes were depleted from tubules at all stages of the spermatogenic cycle at which transferrin is normally expressed. In conclusion, we found that transferrin mRNA expression was not modulated by round spermatids as has been reported previously but that meiotic germ cells may influence expression of transferrin at specific stages of the spermatogenic cycle.
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Mally, Richard, Peter Huemer i Matthias Nuss. "Deep intraspecific DNA barcode splits and hybridisation in the Udea alpinalis group (Insecta, Lepidoptera, Crambidae) – an integrative revision". ZooKeys 746 (13.03.2018): 51–90. http://dx.doi.org/10.3897/zookeys.746.22020.
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The analysis of mitochondrial COI data for the European-Centroasian montaneUdeaalpinalisspecies group finds deep intraspecific splits. Specimens ofU.austriacalisandU.rhododendronalisseparate into several biogeographical groups. These allopatric groups are not recovered in the analyses of the two nuclear markers wingless and Elongation factor 1-alpha, except forU.austriacalisfrom the Pyrenees and the French Massif Central. The latter populations are also morphologically distinct and conspecific withScopuladonzelalisGuenée, 1854, which is removed from synonymy and reinstated asUdeadonzelalis(Guenée, 1854)stat. rev.Furthermore,Udeaaltaica(Zerny, 1914),stat. n.from the Mongolian central Altai mountains,U.juldusalis(Zerny, 1914),stat. n.from the Tian Shan mountains of Kazakhstan, Kyrgyzstan and NW China, andU.plumbalis(Zerny, 1914),stat. n.from the Sayan Mountains of Northern Mongolia are raised to species level, and lectotypes are designated. Evidence of introgression ofU.alpinalisintoU.uliginosalisat three localities in the Central Alps is presented. A screening forWolbachiausing the markers wsp, gatB and ftsZ was negative for theU.alpinalisspecies group, butWolbachiawas found in single specimens ofU.fulvalisandU.olivalis(both in theU.numeralisspecies group). We do not find evidence for the conjecture of several authors of additional subspecies inU.rhododendronalis, and synonymiseU.rhododendronalisluquetalisLeraut, 1996,syn. n.andU.r.ventosalisLeraut, 1996,syn. n.with the nominalU.rhododendronalis(Duponchel, 1834).
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Konings, Pierre N. M., Mo Shahid, Caroline van Alebeek, W. Karolien Makkink, Nico J. Stam, Gé S. F. Ruigt i Patrick M. L. Vanderheyden. "Combined in situ hybridisation, northern blot analysis, and receptor binding studies in clones expressing different levels of the human 5-HT1A receptor". Journal of Receptors and Signal Transduction 15, nr 1-4 (1.01.1995): 443–55. http://dx.doi.org/10.3109/10799899509045232.
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Hurwood, David A., Mike P. Heasman i Peter B. Mather. "Gene flow, colonisation and demographic history of the flat oyster Ostrea angasi". Marine and Freshwater Research 56, nr 8 (2005): 1099. http://dx.doi.org/10.1071/mf04261.
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The Australian flat oyster Ostrea angasi is currently being assessed for its potential as a species for culture in New South Wales. It is considered important to determine the population genetic structure of wild stocks among estuaries before translocation of juveniles (spat) for growout in order to avoid possible deleterious effects of hybridisation of genetically divergent stocks (i.e. outbreeding depression). Five estuaries were sampled in southern New South Wales as well as another four from across the natural range of the species in Australia. Sequence analysis of a 594 base pair fragment of the mitochondrial cytochrome oxidase I gene was used to determine the degree of population structuring inferred from pairwise ΦST estimates and spatial analysis of molecular variance analysis. The analyses revealed that there is no significant genetic differentiation among the sampled New South Wales estuaries (P > 0.05) and all eastern samples represent a geographically homogeneous population. This essentially removes any potential constraints on broodstock sourcing and spat translocation within this region. Although levels of differentiation among all sites varied, little divergence was evident across the entire range of the sample. Furthermore, the study revealed extremely low levels of divergence between O. angasi and its northern hemisphere congener, O. edulis, raising the possibility that O. angasi may have only recently colonised Australian estuaries.
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Jin, Un-Ho, Byung-Rae Jin, Jin-Woo Lee, Young-Su Cho, O.-Chang Kwon, Young-Kil Kim i Chung-Han Chung. "Characterisation of a methionine-rich storage protein cDNA from perilla (Perilla frutescens) seeds". Functional Plant Biology 27, nr 7 (2000): 701. http://dx.doi.org/10.1071/pp99159.
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We have cloned and characterised a cDNA (PrLeg) coding for a methionine-rich storage protein, which is reported for the first time in perilla (Perilla frutescens (L.) Britt. var. Japonica) seeds, homologous to the 11S legumin-like storage proteins. The most significant feature of the PrLeg precursor protein is that it has the highest content of methionine residues among the 11S legumin-like storage proteins examined so far. Another feature is that the deduced amino acid sequences of the PrLeg protein are phylogenetically close to the sequence groups derived from evolutionally ancient states of the 11S legumin-like storage proteins, or from gymnospermous seed storage proteins, such as Magnolia, Asarum, Dioscorea, Cryptomeria, Metasequoia and Ginkgo. In contrast, with the exception of sesame, relatively low phylogenetic relationships are determined between the PrLeg sequence group and those derived from crop plants, such as soybean, pea, broad bean, rape, pumpkin, rice, coffee and citrus. Southern blot analysis suggests that there may be several copy numbers of thePrLeg genes and their seed-specific expression patterns at the transcriptional level were confirmed by northern hybridisation analysis.
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Schmid, P., D. Cox, G. Bilbe, R. Maier i G. K. McMaster. "Differential expression of TGF beta 1, beta 2 and beta 3 genes during mouse embryogenesis". Development 111, nr 1 (1.01.1991): 117–30. http://dx.doi.org/10.1242/dev.111.1.117.
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We have examined by Northern analysis and in situ hybridisation the expression of TGF beta 1, beta 2 and beta 3 during mouse embryogenesis. TGF beta 1 is expressed predominantly in the mesodermal components of the embryo e.g. the hematopoietic cells of both fetal liver and the hemopoietic islands of the yolk sac, the mesenchymal tissues of several internal organs and in ossifying bone tissues. The strongest TGF beta 2 signals were found in early facial mesenchyme and in some endodermal and ectodermal epithelial cell layers e.g., lung and cochlea epithelia. TGF beta 3 was strongest in prevertebral tissue, in some mesothelia and in lung epithelia. All three isoforms were expressed in bone tissues but showed distinct patterns of expression both spatially and temporally. In the root sheath of the whisker follicle, TGF beta 1, beta 2 and beta 3 were expressed simultaneously. We discuss the implication of these results in regard to known regulatory elements of the TGF beta genes and their receptors.
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Fleming, JS, NM Hope i CJ Bolter. "Clusterin is expressed in the anterior and intermediate lobes, but not in the posterior pituitary of sheep". Journal of Molecular Endocrinology 23, nr 2 (1.10.1999): 199–208. http://dx.doi.org/10.1677/jme.0.0230199.
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We have examined the expression of the ovine clusterin gene in the sheep pituitary gland, with the aim of determining its site of synthesis in this tissue. Northern blotting analysis of extracted polyadenylated RNA, using a (32)P-labelled rat clusterin cDNA probe, detected the greatest amounts of clusterin mRNA in the anterior part of dissected pituitary glands. In situ hybridisation studies showed clusterin mRNA in anterior and intermediate pituitary cells, with lower amounts in vascular endothelium and posterior pituicytes. Clusterin protein, detected by immunohistochemistry, was observed in some single secretory cells, within the capillary lumen and in cells around capillaries in the anterior and intermediate lobes, but no immunoreactivity was observed in posterior pituitary tissue. The pattern of clusterin expression in anterior and intermediate pituitary cells suggests possible roles for the protein in secretory cell turnover and/or hormone secretion or lipid uptake. Clusterin does not appear to be involved in ovine posterior pituitary hormone neurosecretion.
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Khoo, Jenny Gaik Imm, i Frank Y. T. Sin. "Molecular cloning and characterisation of a novel membrane receptor gene from the lobster Jasus edwardsii". Journal of Experimental Biology 204, nr 19 (1.10.2001): 3369–77. http://dx.doi.org/10.1242/jeb.204.19.3369.
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SUMMARY The eyestalk of the lobster, Jasus edwardsii, is an important source for hormones involved in the regulation of growth and reproduction. How these hormones transfer their messages to the cell and nucleus is not known. This paper describes the cloning, characterization and expression analyses of two genes that code for two membrane-associated peptides that may be involved in signal transduction. These genes, peJK2 and peJK3, were isolated from a cDNA library derived from lobster eyestalk mRNAs. The two clones shared 96.6 % sequence homology, and code for putative proteins of 110 and 113 amino acids, respectively. These were likely to be two allelic forms of the same gene. Northern blot analysis using these clones as probes detected the same mRNA from eyestalk, muscle and epithelial extracts, but with greater intensity in the eyestalk extract. In situ hybridisation also indicated the predominant expression of these genes in the eyestalk. Analysis of the putative protein sequences showed that they contained two transmembrane (TM) helices, a short amino acid sequence sharing high homology with the G-protein-coupled receptor (GPCR) motif in the second TM, a signal sequence between the TMs, and a protein kinase phosphorylation site at the C termini. Sequence analyses therefore suggested that the deduced peptides may function in signal transduction.
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Schadich, Ermin, Drusilla Mason i Frank Sin. "Co-expressed peJK genes of lobster (Jasus edwardsii)". Australian Journal of Zoology 60, nr 1 (2012): 10. http://dx.doi.org/10.1071/zo11105.
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Previous studies have shown that the two novel genes of southern rock lobster (Jasus edwardsii) named peJK2 and peJK3 are implicated in eyestalk hormonal regulation of the lobster moult cycle. Northern blot, in situ hybridisation studies and sequence analyses showed that their putative products might be transmembrane proteins associated with cell signal transduction of hormonal signals in the eyestalk during the intermoult phase of the moult cycle. The aim of this study was to analyse coexpression of peJK genes in different J. edwardsii tissues. Using reverse transcriptase–polymerase chain reaction (RT-PCR), the expression of peJK genes was analysed in seven different tissues (eyestalk, brain, epidermis, hepatopancreas, gill, muscle and heart) of an intermoult lobster. During RT-PCR analysis, a novel sequence was isolated, and was named peJK4. It shares 88% and 86% sequence identity with peJK2 and peJK3 respectively. The peJK2 and peJK4 genes are expressed in all tested tissues. Sequence analyses of the predicted peJK2 and peJK4 proteins revealed two common signal transduction motifs, transmembrane helices and protein kinase C. These results showed that the peJK genes of J. edwardsii are a complex group of genes and possibly involved in different signal transduction pathways.
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Ishiwata, T., M. Kornmann, H. G. Beger i M. Korc. "Enhanced fibroblast growth factor 5 expression in stromal and exocrine elements of the pancreas in chronic pancreatitis". Gut 43, nr 1 (1.07.1998): 134–39. http://dx.doi.org/10.1136/gut.43.1.134.
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Background—Fibroblast growth factor 5 (FGF-5) belongs to a group of mitogenic and angiogenic heparin binding growth factors but its potential role in chronic inflammatory conditions is not known.Aims—To compare FGF-5 expression in the normal pancreas and in the pancreas of patients with chronic pancreatitis (CP) and to characterise FGF-5 expression and secretion in TAKA-1 cells, an immortalised Syrian hamster pancreatic duct cell line.Methods and results—Northern blotting revealed the presence of a 4.0 kb FGF-5 mRNA transcript in both normal and CP tissue samples. Densitometric analysis indicated that the transcript levels were increased by a factor of 1.44 in CP tissue samples compared with normal tissue samples (p=0.039). By immunohistochemisty and in situ hybridisation, FGF-5 was faintly expressed in ductal and islet cells in the normal pancreas. In contrast, in CP tissue samples, there was abundant expression of FGF-5 in ductal, acinar, and islet cells, as well as in periductal fibroblasts. FGF-5 was also expressed in TAKA-1 cells as determined by Northern blotting. By immunoblotting of heparin-sepharose precipitates, TAKA-1 cells were shown to secrete FGF-5 into the medium.Conclusion—Exocrine and stromal derived FGF-5 has the potential to participate in autocrine and paracrine pathways that may contribute to the pathobiology of chronic pancreatitis.
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Telfer, Wendy R., i Mark D. B. Eldridge. "High levels of mitochondrial DNA divergence within short-eared rock-wallaby (Petrogale brachyotis) populations in northern Australia". Australian Journal of Zoology 58, nr 2 (2010): 104. http://dx.doi.org/10.1071/zo09119.
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Most population genetics studies of rock-wallabies conducted to date have examined remnant colonies of threatened species inhabiting southern Australia. In this study we examined the natural pattern of contemporary and long-term gene flow among colonies of the widespread and abundant short-eared rock-wallaby, Petrogale brachyotis, in the relatively unmodified landscapes of Australia’s tropical north. We sampled 105 wallabies from seven colonies 1.2 km to 250 km apart. Mitochondrial DNA (mtDNA) control region sequence analysis was conducted on samples from all colonies and microsatellite analysis (10 loci) on samples from the three largest colonies. The microsatellite data revealed no evidence of inbreeding within colonies, but higher levels of genetic diversity were found in the Kakadu National Park population compared with the smaller, more isolated colonies at Litchfield National Park. Both the mtDNA and microsatellite results showed that populations of P. brachyotis are naturally highly structured even within this relatively intact landscape, with only limited contemporary and long-term gene flow between colonies more than 1.2 km apart. Nine mtDNA control region haplotypes were identified within the seven colonies. There were unusually high levels of sequence divergence (up to 6.9%) within colonies at Litchfield NP. This divergence suggests that multiple taxa may exist within what is currently recognised as P. brachyotis. Alternatively, if current taxonomy is correct, the high levels of divergence raise the possibility of ancestral isolation and divergence of populations in allopatry with subsequent admixture at a secondary contact zone. The possibility that these unusually divergent haplotypes result from introgressive interspecific hybridisation with the sympatric P. concinna appears unlikely.
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Şahin-Çevik, Mehtap, i Gloria A. Moore. "Two AP2 domain containing genes isolated from the cold-hardy Citrus relative Poncirus trifoliata are induced in response to cold". Functional Plant Biology 33, nr 9 (2006): 863. http://dx.doi.org/10.1071/fp06005.
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Poncirus trifoliata (L.) Raf. is a cold-hardy, interfertile Citrus relative able to tolerate temperatures as low as –26°C when cold acclimated. Therefore, it has been used for improving cold tolerance in cold-sensitive commercial citrus varieties. A cold-induced cDNA library was constructed by subtractive hybridisation of non-acclimated and 2-d cold-acclimated P. trifoliata seedlings and many genes induced in response to cold were identified. Two of these cDNAs, PI-B05 and PI-C10, were selected from this library for further characterisation. Full-length cDNA sequences of these genes were obtained by 5′ and 3′ rapid amplification of cDNA ends (RACE). Sequence analysis revealed that PI-B05 contained an apetala2 / ethylene response factor (AP2 / ERF) domain and showed homology with ERF proteins from other plants, some of which are involved in environmental stress-induced gene expression. PI-C10 contained both AP2 / ERF and B3 DNA binding domains and showed homology with other plant proteins in the RAV subfamily of the AP2 / ERF transcription factors, some of which are induced in response to cold and other environmental stresses. Expression patterns of these genes in cold-tolerant P. trifoliata and cold-sensitive pummelo [Citrus grandis (L.) Osb.] in response to cold and drought at different time points were analysed by northern blots. Expression analysis showed that both genes were induced in response to cold, but not under drought conditions in cold-hardy P. trifoliata. However, little or no expression of these genes was detected by northern analysis in cold-sensitive pummelo under cold or drought conditions. The sequence analysis and expression data indicated that these genes may play a role in cold-responsive gene expression in cold-hardy P. trifoliata and could possibly be used for improving cold tolerance in cold-sensitive citrus cultivars.
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Donnellan, S. C., K. McGuigan, R. Knowles, M. Mahony i C. Moritz. "Genetic evidence for species boundaries in frogs of the Litoria citropa species-group (Anura:Hylidae)". Australian Journal of Zoology 47, nr 3 (1999): 275. http://dx.doi.org/10.1071/zo99013.
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The Litoria citropa species-group comprises several small to medium-sized tree-frog species found from mid-eastern Queensland to eastern Victoria in a variety of habitats along streams associated with the Great Dividing Range. The smaller members of the Litoria citropa species-group, Litoria phyllochroa and L. pearsoniana, have a confused taxonomic history with the taxonomic status of several populations, some regarded as endangered, still in doubt. Multi-locus allozyme electrophoretic profiles and nucleotide sequences of a portion of the mitochondrial 16S ribosomal RNA gene were used to examine the evolutionary relationships of populations that are a geographically comprehensive and morphologically representative sample of the species-group. These data demonstrate the presence of a minimum of three species: L. nudidigitus, L. phyllochroa and a third species whose taxonomic name is yet to be resolved. This third taxon encompasses a wide range of allozyme and mitochondrial nucleotide diversity and can be divided into at least four evolutionarily significant units (ESUs) that replace each other in a linear sequence from north of the Hunter Valley in New South Wales to the Kroombit Tops in central Queensland. A possible zone of hybridisation between the southernmost pair of these ESUs was identified in northern New South Wales. The fourth ESU, a northern outlier of the range of the species-group, is confined to Kroombit Tops, central Queensland.While its phylogenetic relationship with the other three ESUs was not resolved precisely by the present analysis, it nevertheless comprises a distinct and very divergent mitochondrial lineage of considerable antiquity.Resolution of the status of a further name applied to the species-group, L. piperata, awaits a morphological analysis that includes the relevant type material.
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Jang, You-Jee, Jae-Il Park, Seong-Eun Jeong, You-Mi Seo, Phuong T. M. Dam, Young-Woo Seo, Bum-Chae Choi, Sang-Jin Song, Sang-Young Chun i Moon-Kyoung Cho. "Regulation of interleukin-11 expression in ovulatory follicles of the rat ovary". Reproduction, Fertility and Development 29, nr 12 (2017): 2437. http://dx.doi.org/10.1071/rd16460.
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The aim of the present study was to examine the regulation of interleukin (IL)-11 expression, as well as the role of IL-11, during ovulation in gonadotropin-primed immature rats. Injection of equine chorionic gonadotropin (eCG), followed by human CG (hCG) to induce superovulation stimulated expression of the Il11 gene in theca cells within 6 h, as revealed by northern blot and in situ hybridisation analyses. Real-time reverse transcription–polymerase chain reaction analysis showed that the IL-11 receptor, α subunit gene was expressed in granulosa and theca cells and that injection of hCG had no effect on its expression. IL-11 protein expression was stimulated in theca cells by hCG. LH-stimulated increases in Il11 mRNA levels in cultured preovulatory follicles were inhibited by protein kinase A and mitogen-activated protein kinase kinase inhibitors. Toll-like receptor (TLR) 2 and TLR4 were detected in preovulatory follicles, and the TLR4 ligand lipopolysaccharide, but not the TLR2 ligand Pam3Cys, increased Il11 mRNA levels in theca cells, but not in granulosa cells. Treatment of preovulatory follicles with IL-11 stimulated progesterone production and steroidogenic acute regulatory protein (Star) gene expression. Together, these results indicate that IL-11 in theca cells is stimulated by mitogen-activated protein kinase signalling and TLR4 activation, and increases progesterone production during ovulation.
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Mokhtar, N. M., S. K. Smith i D. Charnock-Jones. "126. Progesterone regulates CXCL14 (macrophage inflammatory protein 2γ) mRNA in human endometrium". Reproduction, Fertility and Development 17, nr 9 (2005): 75. http://dx.doi.org/10.1071/srb05abs126.
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The emergence of microarray technology has enabled a thorough study of the level of transcripts in the human body. A high density micoarray analysis revealed a comprehensive list of transcripts, which were significantly different between mid-proliferative and mid-secretory phase endometrium.2 An EST identified from the HG_U95B chip is identical to the 3′UTR of CXCL14 or macrophage inflammatory protein 2γ (MIP 2γ). The level is 19-fold higher in the mid-secretory compared to the mid-proliferative phase of menstrual cycle. This has suggested that the transcript level of CXCL14 may be directly regulated by progesterone. Northern hybridisation and in situ hybridisation confirmed that the transcript level of CXCL14 (MIP 2γ) was high in the mid-to-late secretory endometrium and its mRNA was localised in the glandular epithelium of this tissue.1 In silico analysis has predicted six progesterone response elements (PREs) within 2040 bp upstream from the ATG site. To investigate the possible functions of these PREs, a dual luciferase assay was performed on the ishikawa cell line transfected with five deletion constructs of the gene promoter. Cells were co-transfected with progesterone receptor B (PRB) and treated with 10–6 M progesterone. Luciferase activities of these constructs have localised two fragments that were most likely to contain the active PREs, i.e. PRE1 and PRE2. An electrophoretic mobility shift assay showed that PRE oligonulcleotides within these two regions were able to bind PRB that was synthesised in vitro, although there was a stronger signal seen in the PRE2 region. A dose competition study revealed PRE1/PRB and PRE2/PRB protein binding could be competed with different concentrations of cold wild-type competitor oligonucleotides. Mutagenesis of PRE1 and PRE2 analysed by luciferase reporter assay reduced the inductive effect of progesterone treatment. This study indicates that progestegen induced transcript encoding a chemokine in the human endometrium may likely act as a chemoattractant for leucocytes during the secretory phase of the menstrual cycle. (1)Mokhtar NM, Smith SK, Charnock-Jones DS. (2003). Characterisation of chemokine macrophage inflammatory protein 2gamma mRNA in human endometrium. 50th Society for Gynaecologic Investigation. Washington DC, USA. March 2003.(2)Borthwick JM, Charnock-Jones DS, Tom BD, Hull ML, Teirney R, Phillip SC, Smith SK. (2003). Determination of the transcript profile of human endometrium. Mol. Hum. Reprod. 9, 19–33.
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Fjeldheim, Åse-Karine, Per Ivar Høvring, Ole-Petter Løseth, Per Wiik Johansen, Joel C. Glover, Vilborg Matre, Ole Kristoffer Olstad i in. "Thyrotrophin-releasing hormone receptor 1 and prothyrotrophin-releasing hormone mRNA expression in the central nervous system are regulated by suckling in lactating rats". European Journal of Endocrinology 152, nr 5 (maj 2005): 791–803. http://dx.doi.org/10.1530/eje.1.01902.
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Background: The accepted function of the hypothalamic peptide, thyrotrophin-releasing hormone (TRH), is to initiate release of thyrotrophin (TSH) from the pituitary. A physiological role for TRH in lactating rats has not yet been established. Methods: Tissues were prepared from random-cycling and lactating rats and analysed using Northern blot, real time RT-PCR and quantitative in situ hybridisation. Results: This study demonstrates that TRH receptor 1 (TRHR1) mRNA expression is up-regulated in the pituitary and in discrete nuclei of the hypothalamus in lactating rats, while proTRH mRNA expression levels are increased only in the hypothalamus. The results were corroborated by quantitative in situ analysis of proTRH and TRHR1. Bromocriptine, which reduced prolactin (PRL) concentrations in plasma of lactating and nursing rats, also counteracted the suckling-induced increase in TRHR1 mRNA expression in the hypothalamus, but had an opposite effect in the pituitary. These changes were confined to the hypothalamus and the amygdala in the brain. Conclusions: The present study shows that the mechanisms of suckling-induced lactation involve region-specific regulation of TRHR1 and proTRH mRNAs in the central nervous system notably at the hypothalamic level. The results demonstrate that continued suckling is critical to maintain plasma prolactin (PRL) levels as well as proTRH and TRHR1 mRNA expression in the hypothalamus. Increased plasma PRL levels may have a positive modulatory role on the proTRH/TRHR1 system during suckling.
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Holmes, Gareth D., Trisha L. Downing, Elizabeth A. James, Mark J. Blacket, Ary A. Hoffmann i Michael J. Bayly. "Phylogeny of the holly grevilleas (Proteaceae) based on nuclear ribosomal and chloroplast DNA". Australian Systematic Botany 27, nr 1 (2014): 56. http://dx.doi.org/10.1071/sb13045.
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The holly grevilleas are an informal grouping of 15 species (19 taxa) of woody shrubs from south-eastern Australia, with a centre of distribution in central to western Victoria. Many of the species are narrowly endemic. The present study is the first molecular-phylogenetic analysis of the group, with the aim of providing an evolutionary framework for assessing species-level taxonomy and conservation priorities. Analyses using the nrDNA internal transcribed spacer (ITS) regions were complicated by the presence of divergent paralogues, including inferred pseudogenes; analyses restricted to presumed orthologous, functional ITS sequences were uninformative. Combined analyses of three chloroplast intergenic spacers (trnQ–5′rps16, trnL–trnF and rpoB–trnC) strongly support the monophyly of a core group of 16 taxa (the ‘southern holly grevilleas’) from Victoria and South Australia. However, nodes outside this group are poorly resolved and poorly supported, and the relationships of taxa from New South Wales and eastern Victoria (the ‘northern holly grevilleas’) are unclear. Among the southern holly grevilleas, the following four distinct and partly sympatric cpDNA clades are identified: the ‘Grevillea ilicifolia’, ‘G. aquifolium’, ‘G. dryophylla’ and ‘G. repens’ clades, among which the earliest and most strongly supported divergence is that of the western-most ‘G. ilicifolia’ clade. Variation in cpDNA is incongruent with current species-level taxonomy, especially for G. aquifolium (polyphyletic), G. montis-cole (polyphyletic, but the two subspecies each monophyletic) and G. microstegia (nested in G. aquifolium). The effects of incomplete chloroplast lineage sorting, gene flow through hybridisation or introgression, and inappropriate taxonomy are possible explanations for this incongruence. The formal conservation listing for some species within the holly grevillea group requires re-evaluation.
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Smith, CA, V. Clifford, PS Western, SA Wilcox, KS Bell i AH Sinclair. "Cloning and expression of a DAX1 homologue in the chicken embryo". Journal of Molecular Endocrinology 24, nr 1 (1.02.2000): 23–32. http://dx.doi.org/10.1677/jme.0.0240023.
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DAX1 is an unusual member of the orphan nuclear receptor family of transcription factors. Mutations in human DAX1 cause X-linked adrenal hypoplasia congenita, while abnormal duplication of the gene is responsible for male-to-female dosage-sensitive sex reversal. Based on these and other observations, DAX1 is thought to play a role in adrenal and gonadal development in mammals. As DAX1 has not previously been described in any other vertebrate, a putative avian DAX1 clone was isolated from an embryonic chicken (Gallus domesticus) urogenital ridge cDNA library. The expression profile of this cDNA was then examined during gonadogenesis. The clone included the conserved 3' ligand-binding motif identified in humans and mice but the 5' region lacked the repeat motif thought to specify a DNA-binding domain in mammals. Southern blot analysis and fluorescence in situ hybridisation mapping showed that the gene is autosomal, located on chromosome 1q. Sequence comparisons showed that the putative chicken DAX1 protein has 63 and 60% identity with the human and mouse proteins respectively over the region of the conserved ligand-binding domain. However, stronger identity (74%) exists with a putative alligator DAX1 sequence over the same region. Northern blotting detected a single 1.4 kb transcript in late embryonic chicken gonads, while RNase protection assays revealed expression in the embryonic gonads of both sexes during the period of sexual differentiation. Expression increased in both sexes during gonadogenesis, but was higher in females than in males. This is the first description of a DAX1 homologue in a non-mammalian vertebrate.
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O'Bryan, MK, KL Sebire, O. Gerdprasert, MP Hedger, MT Hearn i DM de Kretser. "Cloning and regulation of the rat activin betaE subunit". Journal of Molecular Endocrinology 24, nr 3 (1.06.2000): 409–18. http://dx.doi.org/10.1677/jme.0.0240409.
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Using a combination of polymerase chain reaction (PCR) procedures, we have cloned and sequenced the rat activin beta(E) subunit cDNA. The putative protein corresponding to the prepro-activin beta(E) subunit was predicted to comprise 350 amino acids which, when cleaved between amino acid residues 236 and 237, would yield a mature polypeptide of approximately M(r) 12 500 with a predicted pI of 5.1. Two cDNA transcripts for activin beta(E) were identified; these differed by 738 bp in the 3'-untranslated region. Activin beta(E) mRNA transcripts were expressed only in rat liver and lung tissue as assessed by Northern blotting and PCR analysis. Relatively higher levels of both transcripts were found in the liver, whereas the lung contained lower levels that were detectable by PCR only. In situ hybridisation data showed that, within the liver, activin beta(E) mRNA was localised to hepatocytes. In vivo treatment with lipopolysaccharide as a means of activating the immune system and the hepatic acute-phase response resulted in stimulated activin beta(E) mRNA levels, compared with untreated, control rats. This increased expression was accompanied by a preferential increase in the amount of the long activin beta(E) transcript over the shorter transcript. These findings suggested that the two activin beta(E) mRNA transcripts may be products of alternative splicing events or use alternative polyadenylation sites which are differentially regulated during inflammation. These data provide evidence of a role for activin beta(E) in liver function and inflammation in the rat.
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Hidayani, Andi Aliah, Asmi Citra Malina A. R. Tasakka, Widyastuti Umar, Md Jobaidul Alam, Amit Kumer Neogi i Sapto Andriyono. "Low Genetic Diversity Study on Leopard Coral Grouper Plectropomus leopardus (Perciformes: Serranidae) from Sulawesi, Indonesia". Jurnal Ilmiah Perikanan dan Kelautan 14, nr 2 (30.08.2022): 349–59. http://dx.doi.org/10.20473/jipk.v14i2.32815.
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Highlight ResearchThe leopard coral grouper Plectropomus leopardus was identified and analysed based on molecular approach.Genetic diversity within two regions in Gorontalo, Sulawesi successfully performed using connectivity analysis.Three haplotypes of Plectropomus leopardus from two region in Gorontalo as one of economical important marine fish species. AbstractBar-cheek coral trout (P. leopardus) is the flagship of the grouper in the live fish market in Asia. Unfortunately, the potential of the grouper is still partly produced from natural catches. Even though hybridisation activities have also started to be carried out, there still have not been many studies on the genetic diversity of these fish. The application of molecular identification has been widely applied in marine aquatic animal species, which are very likely to occur due to errors in terms of shape and colour in the morphological character. DNA information has been beneficial in efforts to the breeding program and develop grouper aquaculture activities. DNA barcoding was used for the molecular identification and haplotype analysis of P. leopardus from two locations in Gorontalo, Sulawesi, Indonesia. A total of 14 fish samples were collected from two traditional fish markets around Kwandang and Sumalata Gulf in the northern part of Gorontalo Province, Sulawesi. This study identified and found three haplotypes from both regions. Molecular identification using Cytochrome c Oxidase subunit I (COI) gene region on mitochondrial DNA. Besides Mega7 for phylogenetic reconstruction, the data analysis using DnaSP6, Arlequin Ver.3.5.2.2, and Network 5.0.1.1. The first Haplotype is a mixed population between the Kwandang Gulf and the Sumalata Gulf, then the Kwandang Gulf haplotype and the Sumalata Gulf haplotype. The genetic distance between Kwandang Gulf haplotype and Sumalata Gulf haplotype is 0.003984, classified as a shallow genetic distance and needs more samples from another region to figure out leopard coral grouper around Indonesia.
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Dekker, E. J., M. J. Vaessen, C. van den Berg, A. Timmermans, S. Godsave, T. Holling, P. Nieuwkoop, A. Geurts van Kessel i A. Durston. "Overexpression of a cellular retinoic acid binding protein (xCRABP) causes anteroposterior defects in developing Xenopus embryos". Development 120, nr 4 (1.04.1994): 973–85. http://dx.doi.org/10.1242/dev.120.4.973.
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We have isolated the first Xenopus laevis cDNA coding for a cellular retinoic acid binding protein (xCRABP). xCRABP contains a single open reading frame, coding for an approximately 15 × 10(3) M(r) protein. Northern blot analysis shows that this cDNA hybridizes to a mRNA that is expressed both maternally and zygotically and which already reaches maximal expression during gastrulation (much earlier than previously described CRABP genes from other species). In situ hybridisation showed that at the onset of gastrulation, xCRABP mRNA is localised at the dorsal side of the embryo, in the ectoderm and in invaginating mesoderm. xCRABP expression then rapidly resolves into two domains; a neural domain, which becomes localised in the anterior hindbrain, and a posterior domain in neuroectoderm and mesoderm. These two domains were already evident by the mid-gastrula stage. We investigated the function of xCRABP by injecting fertilized eggs with an excess of sense xCRABP mRNA and examined the effects on development. We observed embryos with clear antero-posterior defects, many of which resembled the effects of treating Xenopus gastrulae with all-trans retinoic acid. Notably, the heart was deleted, anterior brain structures and the tail were reduced, and segmentation of the hindbrain was inhibited. The effects of injecting xCRABP transcripts are compatible with the idea that xCRABP overexpression modulates the action of an endogenous retinoid, thereby regulating the expression of retinoid target genes, such as Hox genes. In support of this, we showed that the expression of two Xenopus Hoxb genes, Hoxb-9 and Hoxb-4, is strongly enhanced by xCRABP over-expression. These results suggest that xCRABP expression may help to specify the anteroposterior axis during the early development of Xenopus laevis.
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Andrew, Rose L., Joseph T. Miller, Rod Peakall, Michael D. Crisp i Randall J. Bayer. "Genetic, cytogenetic and morphological patterns in a mixed mulga population: evidence for apomixis". Australian Systematic Botany 16, nr 1 (2003): 69. http://dx.doi.org/10.1071/sb01043.
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The mulga complex (Acacia aneura and closely related taxa) is a widespread group that is dominant in much of arid Australia. The group is taxonomically difficult, due to a complex interaction of sympatry and putative hybridisation between the major species, geographic variation within species and sympatric variation within A. aneura. Mulga is highly variable in a wide range of vegetative and reproductive characters and it is not unusual to find five or six distinct forms growing side by side. The aim of this project was to gain a better understanding of the relationships among mulga species and A. aneura varieties, as well as the maintenance of this variation. A single site in the Northern Territory, containing A. ayersiana, A. minyura and two varieties of A. aneura, was sampled intensively. Six morphotypes were observed in the field and five were strongly supported by morphometric analysis. Although the mulga complex is generally tetraploid (2n = 52), triploid (2n = 39) and pentaploid (2n = 65) seedlings were produced in the study population. Microsatellite primers developed for A. mangium (sect. Juliflorae) were amplified in individuals of each morphotype, resulting in genetic marker patterns consistent with polyploidy. Genetic and morphometric distances were correlated and differences between morphotypes account for 63% of the total genetic variation (ΦPT = 0.63, P < 0.001). Allele sequences confirmed the presence of genuine heterozygosity and clonality was suggested by the low genotypic diversity and the lack of allele segregation. Seedlings had identical genotypes to the maternal plants and polyembryony was observed in each taxon, consistent with apomictic reproduction. Both variation of the ploidy level and apomixis may restrict gene flow among morphotypes, playing a role in the maintenance of morphological diversity at the study site. The success of the group in arid and semi-arid Australia may also be due, in part, to these factors.
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Hopkins, Mark J., George T. Macfarlane, Elizabeth Furrie, Alemu Fite i Sandra Macfarlane. "Characterisation of intestinal bacteria in infant stools using real-time PCR and northern hybridisation analyses". FEMS Microbiology Ecology 54, nr 1 (wrzesień 2005): 77–85. http://dx.doi.org/10.1016/j.femsec.2005.03.001.
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Chaplin, Kirilee, Katie Smith Date, Rebecca D. Bray, Kimberly A. Miller, Maiko L. Lutz, Emma Razeng, Michael B. Thompson i David G. Chapple. "Intraspecific hybridisation of an invasive lizard on Lord Howe Island". Australian Journal of Zoology 69, nr 5 (2.08.2022): 184–96. http://dx.doi.org/10.1071/zo21045.
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Human-mediated dispersal of animals often acts to bring populations that have been separated for substantial periods of evolutionary time (e.g. millions of years) in their native range into contact in their introduced range. Whether these taxa successfully interbreed in the introduced range provides information on the strength of reproductive isolation amongst them. The invasive delicate skink (Lampropholis delicata) has been accidentally introduced to Lord Howe Island from four genetically divergent (>2 million years) regions of the species’ native range in eastern Australia. We used mitochondrial DNA and microsatellite data to investigate whether the individuals from four of the native-range source regions are interbreeding on Lord Howe Island. Our analyses indicate that intraspecific hybridisation among individuals from all four native-range source regions is occurring. Although there is little evidence for hybrids in the northern end of Lord Howe Island (proportion of hybrids: 0–0.02; n = 31), there is a high proportion of hybrids in the central (0.33–0.69; n = 59) and southern regions (0.38–0.75; n = 8) of the island. Given the strong evidence for interbreeding among all four native-range source regions examined, and the relatively minor morphological, life-history and phenotypic variation among them, we suggest that the delicate skink should continue to be treated as a single, widespread, but variable species.
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Godjo, Anique, Leonard Afouda, Hugues Baimey, Marjolein Couvreur, Lionel Zadji, Gladys Houssou, Wim Bert, Anne Willems i Wilfrida Decraemer. "Steinernema kandii n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from northern Benin". Nematology 21, nr 2 (2019): 107–28. http://dx.doi.org/10.1163/15685411-00003201.
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Summary Two nematode isolates from the genus Steinernema were collected in northern Benin. Morphological, morphometric, molecular and cross-hybridisation studies placed these nematodes into a new species, Steinernema kandii n. sp., within the bicornutum-group. Phylogenetic analyses based on both ITS and D2-D3 regions of 28S rDNA revealed that S. kandii n. sp. is different from all known Steinernema species and sister to S. abbasi (97.3-97.6% ITS nucleotide similarity) and S. bifurcatum (98.3-98.4% D2-D3 similarity). Steinernema kandii n. sp. can be separated from other members of the bicornutum-group by the greater infective juvenile (IJ) max. body diam. of 35 (27-48) μm (type isolate). It differs from S. abbasi by the greater IJ body length 707 (632-833) μm (type isolate), EP distance 55 (52-60) μm (type isolate), spicule length 67 (57-75) μm (type isolate) and the occurrence of one pair of genital papillae at the cloacal aperture.
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Weinmaster, G., V. J. Roberts i G. Lemke. "Notch2: a second mammalian Notch gene". Development 116, nr 4 (1.12.1992): 931–41. http://dx.doi.org/10.1242/dev.116.4.931.
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Notch is a cell surface receptor that mediates a wide variety of cellular interactions that specify cell fate during Drosophila development. Recently, homologs of Drosophila Notch have been isolated from Xenopus, human and rat, and the expression patterns of these vertebrate proteins suggest that they may be functionally analogous to their Drosophila counterpart. We have now identified a second rat gene that exhibits substantial nucleic and amino acid sequence identity to Drosophila Notch. This gene, designated Notch2, encodes a protein that contains all the structural motifs characteristic of a Notch protein. Thus, mammals differ from Drosophila in having more than one Notch gene. Northern and in situ hybridisation analyses in the developing and adult rat identify distinct spatial and temporal patterns of expression for Notch1 and Notch2, indicating that these genes are not redundant. These results suggest that the great diversity of cell-fate decisions regulated by Notch in Drosophila may be further expanded in vertebrates by the activation of distinct Notch proteins.
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Whiffin, T., i PY Ladiges. "Patterns of variation and relationships in the Eucalyptus Alpina–E. baxteri complex (Myrtaceae) based on leaf volatile oils". Australian Systematic Botany 5, nr 6 (1992): 695. http://dx.doi.org/10.1071/sb9920695.
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In the stringybark eucalypts, the baxteri clade consists of E. arenacea, from South Australia and northwestern Victoria, E. baxteri, mainly from the Great Dividing Range of Victoria, and E. alpina, an endemic taxon from the Grampian Ranges of Victoria. Populations of these taxa were sampled from across their geographic and morphological ranges. Phenetic and phylogenetic analyses were undertaken of the leaf volatile oil composition of the sampled plants. On the basis of these analyses, E. arenacea emerges as a cohesive, monophyletic species, while E. baxteri is a variable and probably paraphyletic species. Populations on Kangaroo Island, South Australia, are variable and intermediate, and may represent recent intergradation between the two species. Populations of E. baxteri from the Grampians are distinctive chemically, but not morphologically, within the species. Recent hybridisation between this form of E. baxteri and E. alpina was shown to be occuning within the Grampians. E. alpina is a highly variable taxon, and probably polyphyletic as currently recognised. Three distinct forms were recognised within E. alpina. The first, and most distinctive, is from the southern Serra Range; the second is from the northern Serra Range and Wonderland Range; the third, and most similar to E. baxteri, is from the Victoria Range.
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Mischler, Claudia, Andrew Veale, Tracey van Stijn, Rudiger Brauning, John McEwan, Richard Maloney i Bruce Robertson. "Population Connectivity and Traces of Mitochondrial Introgression in New Zealand Black-Billed Gulls (Larus bulleri)". Genes 9, nr 11 (9.11.2018): 544. http://dx.doi.org/10.3390/genes9110544.
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Black-billed gulls (Larus bulleri) are endemic to New Zealand and are suspected to be undergoing substantial population declines. They primarily breed on open gravel beds in braided rivers of the South Island—a habitat that is diminishing and becoming increasingly modified. Although management of this species is increasing, little has been published on their movements and demographics. In this study, both mitochondrial DNA (mtDNA) control region domain I and nuclear single nucleotide polymorphisms (SNPs) were examined to help understand the connectivity and population structure of black-billed gulls across the country and to help inform management decisions. Mitochondrial DNA showed no population structure, with high haplotype and low nucleotide diversity, and analyses highlighted mitochondrial introgression with the closely related red-billed gulls (Larus novaehollandiae scopulinus). Nuclear DNA analyses, however, identified two groups, with Rotorua birds in the North Island being distinct from the rest of New Zealand, and isolation-by-distance evident across the South Island populations. Gene flow primarily occurs between nearby colonies with a stepwise movement across the landscape. The importance from a genetic perspective of the more isolated North Island birds (1.6% of total population) needs to be further evaluated. From our results, we infer that the South Island black-billed gull management should focus on maintaining several populations within each region rather than focusing on single specific colonies or river catchments. Future study is needed to investigate the genetic structure of populations at the northern limit of the species’ range, and identify the mechanisms behind, and extent of, the hybridisation between red-billed and black-billed gulls.
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Ma, Juan, Juan Ma, Shulong Chen, Juan Ma, Shulong Chen, Patrick De Clercq, Juan Ma i in. "A new entomopathogenic nematode, Steinernema xinbinense n. sp. (Nematoda: Steinernematidae), from north China". Nematology 14, nr 6 (2012): 723–39. http://dx.doi.org/10.1163/156854112x627273.
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During a survey for entomopathogenic nematodes in northern China, a new species of Steinernema was isolated from soil samples collected from Xinbin county, Liaoning province. This nematode was obtained by the insect-baiting technique using last instar larvae of Galleria mellonella. It is described herein as S. xinbinense n. sp. The nematode can be separated from other described species of the group by morphological and morphometric characteristics of the different stages and by characterisation and phylogeny of DNA sequences of the D2D3 domain of the LSU or ITS regions of rDNA. This new species is characterised by the following morphological characters: infective third-stage juvenile with a body length of 694 (635-744) μm, distance from head to excretory pore of 51 (46-53) μm, tail length of 73 (61-81) μm, E = 71 (65-78)%, presence of eight unevenly spaced and developed ridges in middle lateral field (i.e., nine lines). First generation male with well curved, yellowish spicules 56 (49-62) μm long and gubernaculum 35 (30-41) μm long, small mucron mostly present, first generation female with protruding vulva, tail conical with one or two small mucrons and D = 45 (41-50)%. Cross hybridisation tests with S. tielingense, S. kraussei, S. feltiae and S. hebeiense showed that this species was reproductively isolated. The analyses of ITS-rDNA and D2D3 sequence confirm that the studied nematode isolate is a valid new species belonging to the ‘feltiae-kraussei-oregonense’ group.
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Yu, H., Y. Hu, A. J. Pask, G. Shaw i M. B. Renfree. "245. Aristaless-related homeobox gene is involved in early development and spermatogenesis in mammals". Reproduction, Fertility and Development 20, nr 9 (2008): 45. http://dx.doi.org/10.1071/srb08abs245.
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The aristaless homeobox gene, ARX, belongs to a large family of homeodomain transcription factors with essential roles in forebrain, pancreas, muscle tissues and testes development in human and mouse. Mutation of ARX in humans results in mental retardation with or without ambiguous genitalia. We used comparative analyses to examine the evolutionary conservation of the mammalian ARX gene. We characterised ARX in a marsupial, the tammar wallaby, to determine if this gene is highly conserved in the homeodomain, aristaless domain, octapeptide motif and polyalanine tracts of all mammals. We further investigated the mRNA distribution in the developing head of tammar with in situ hybridisation, and found that it is expressed in forebrain and olfactory bulb as expected. Besides these regions, very strong expression was detected in the epithelium of the tongue and nasal pits. In the gonads, there is very strong staining in the interstitial cells and some of the germ cells in the developing ovary; strong staining was also seen in the cytoplasm of Sertoli cells and some of the germ cells, weak staining was also detected in the interstitium of the testis, possibly within the vessel endothelial cells and interstitial fibroblast-like cells. In addition, we investigated mRNA distribution in adult testes based on a very strong signal observed with northern blotting. Interestingly, mRNA expression was restricted to the round spermatids, and was not seen before or after this stage. In order to confirm this new role for ARX in the adult testis, we further investigated mRNA distribution of Arx in adult mouse testis, and found the same expression pattern, which implies a conserved function for ARX in spermatogenesis and may explain why humans with ARX mutations are infertile. This is the first report that ARX gene is involved in spermatogenesis in addition to its conserved roles in early mammalian development.
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Martin Cerezo, Maria Luisa, Saioa López, Lucy van Dorp, Garrett Hellenthal, Martin Johnsson, Eben Gering, Rie Henriksen i Dominic Wright. "Population structure and hybridisation in a population of Hawaiian feral chickens". Heredity, 1.02.2023. http://dx.doi.org/10.1038/s41437-022-00589-z.
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AbstractChickens are believed to have inhabited the Hawaiian island of Kauai since the first human migrations around 1200AD, but numbers have peaked since the tropical storms Iniki and Iwa in the 1980s and 1990s that destroyed almost all the chicken coops on the island and released large numbers of domestic chickens into the wild. Previous studies have shown these now feral chickens are an admixed population between Red Junglefowl (RJF) and domestic chickens. Here, using genetic haplotypic data, we estimate the time of the admixture event between the feral population on the island and the RJF to 1981 (1976–1995), coinciding with the timings of storm Iwa and Iniki. Analysis of genetic structure reveals a greater similarity between individuals inhabiting the northern and western part of the island to RJF than individuals from the eastern part of the island. These results point to the possibility of introgression events between feral chickens and the wild chickens in areas surrounding the Koke’e State Park and the Alaka’i plateau, posited as two of the major RJF reservoirs in the island. Furthermore, we have inferred haplotype blocks from pooled data to determine the most plausible source of the feral population. We identify a clear contribution from RJF and layer chickens of the White Leghorn (WL) breed. This work provides independent confirmation of the traditional hypothesis surrounding the origin of the feral populations and draws attention to the possibility of introgression of domestic alleles into the wild reservoir.
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Ginibun, Florence C., Paul Arens, Ben Vosman, Subha Bhassu, Norzulaani Khalid i Rofina Yasmin Othman. "Genetic diversity of endangered terrestrial orchids Spathoglottis plicata in Peninsular Malaysia based on AFLP markers". Plant Omics, nr 11(03) 2018 (20.11.2018). http://dx.doi.org/10.21475/poj.11.03.18.p1227.
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Spathoglottis plicata is an endangered terrestrial orchid species that have experienced severe threats to its habitat as wild forest sites come under pressure from industrialisation and natural disasters. This orchid species chosen to evaluate their levels of genetic diversity and population genetic structure, which 25-30 accession collected in the different location with different geographical, altitude and habitat. Genomic DNA was extracted from six natural populations (n=172) in Peninsular Malaysia using eleven AFLP markers of EcoRI+3 bases/MseI+3 base primer combinations. Based on 279 polymorphic bands, a significant degree of genetic population differentiation was found, with a 78.5% variation within populations as measured by AMOVA, indicating a potential restricted gene flow. Two distinct clades generated from a UPGMA dendrogram were further investigated through a Bayesian analysis using STRUCTURE software, producing an estimated population structure at optimal value K=4. These results point to the presence of four genetic structures in the Spathoglottis plicata population. The Pahang and Terengganu population revealed a higher than average genetic variation (60.25%), indicating that there may be a robust structural division between the population samples and a possible hybridisation between the Northern (Kedah), Southern (Negeri Sembilan and Johor) and Central (Selangor) region populations. In sum, these results suggest that geographical distance is the primary factor contributing to differences among populations and the need for conservation measures to protect the Spathoglottis plicata species.
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Giménez, Mabel D., Jonathan J. Hughes, Moira Scascitelli, Sofia I. Gabriel, Daniel W. Förster, Thadsin Panithanarak, Heidi C. Hauffe i Jeremy B. Searle. "Tracking Chromosomal Origins in the Northern Italy System of Metacentric Races of the House Mouse". Cytogenetic and Genome Research, 1.12.2022, 1–16. http://dx.doi.org/10.1159/000527106.
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The Western European house mouse is chromosomally diverse, with diploid karyotypes ranging from the standard 40 telocentric chromosomes down to 22 chromosomes. Karyotypes are modified through Robertsonian (Rb) fusion of 2 telocentrics into a single metacentric, occurring repeatedly with fixation, and whole-arm reciprocal translocations (WARTs) generating additional novel karyotypes. Over 100 metacentric populations (chromosomal races) have been identified, geographically clustered into “systems.” Chromosomal races within systems often hybridise, and new races may emerge through this hybridisation (“zonal raciation”). We wished to determine the degree to which chromosomal races in a system have evolved independently or share common ancestry. Recombination between chromosomes from hybridising chromosomal races can erase the signals associated with a particular metacentric of interest, making inferences challenging. However, reduced recombination near the centromeres of chromosomal race-specific metacentrics makes centromere-adjacent markers ideal for solving this problem. For the Northern Italy System (NIS), we used microsatellite markers near the centromere to test previous hypotheses about evolutionary relationships of 5 chromosomal races. We chose markers from chromosomes 1, 3, 4, and 6, all of which comprise one arm of a metacentric in at least 2 of these NIS metacentric populations. We used estimates of F<sub>ST</sub> and R<sub>ST</sub>, as well as principal components analyses and neighbour-joining phylogenetic analyses, to infer evolutionary relationships between these 5 chromosomal races and neighbouring mice with the standard karyotype. We showed that the metacentric populations form a single grouping distinct from the standard populations, consistent with their common origin and consistent with a parsimonious sequence of chromosomal rearrangements to explain the relationship of the chromosomal races. That origin and evolution of the chromosomal races in the system would have involved Rb fusions, explaining the occurrence of chromosomal races with diploid numbers as low as 22. However, WARTs and zonal raciation have also been inferred, and the rare occurrence of chromosome 1 in different metacentrics in closely related chromosomal races is almost certainly explained by a WART. Our results with centromeric microsatellites are consistent with the above scenarios, illustrating, once again, the value of markers in the centromeric region to test evolutionary hypotheses in house mouse chromosomal systems.