المؤلفون: Gostinčar, Cene, Stajich, Jason E, Zupančič, Jerneja, Zalar, Polona, Gunde-Cimerman, Nina

المصدر: BMC Genomics. 19(1)

مصطلحات موضوعية: Microbiology, Biological Sciences, Genetics, Biotechnology, Human Genome, Ascomycota, Diploidy, Ecosystem, Genome, Fungal, Genomics, Hybridization, Genetic, Phylogeny, Whole genome duplication, Hybridization, Clonal reproduction, Restricted recombination, Halotolerance, Polyextremotolerance, Salt stress, Black yeast, Ploidy, Information and Computing Sciences, Medical and Health Sciences, Bioinformatics, Biological sciences, Biomedical and clinical sciences

الوصف: BackgroundThe black yeast Hortaea werneckii (Dothideomycetes, Ascomycota) is one of the most extremely halotolerant fungi, capable of growth at NaCl concentrations close to saturation. Although dothideomycetous fungi are typically haploid, the reference H. werneckii strain has a diploid genome consisting of two subgenomes with a high level of heterozygosity.ResultsIn order to explain the origin of the H. werneckii diploid genome we here report the genome sequencing of eleven strains isolated from different habitats and geographic locations. Comparison of nine diploid and two haploid strains showed that the reference genome was likely formed by hybridization between two haploids and not by endoreduplication as suggested previously. Results also support additional hybridization events in the evolutionary history of investigated strains, however exchange of genetic material in the species otherwise appears to be rare. Possible links between such unusual reproduction and the extremotolerance of H. werneckii remain to be investigated.ConclusionsH. werneckii appears to be able to form persistent haploid as well as diploid strains, is capable of occasional hybridization between relatively heterozygous haploids, but is otherwise limited to clonal reproduction. The reported data and the first identification of haploid H. werneckii strains establish this species as a good model for studying the effects of ploidy and hybridization in an extremotolerant system unperturbed by frequent genetic recombination.

وصف الملف: application/pdf

URL الوصول: https://escholarship.org/uc/item/2jb7q436

المؤلفون: Cene Gostinčar, Jason E. Stajich, Jerneja Zupančič, Polona Zalar, Nina Gunde-Cimerman

المصدر: BMC Genomics, Vol 19, Iss 1, Pp 1-12 (2018)

مصطلحات موضوعية: Whole genome duplication, Hybridization, Clonal reproduction, Restricted recombination, Halotolerance, Polyextremotolerance, Biotechnology, TP248.13-248.65, Genetics, QH426-470

الوصف: Abstract Background The black yeast Hortaea werneckii (Dothideomycetes, Ascomycota) is one of the most extremely halotolerant fungi, capable of growth at NaCl concentrations close to saturation. Although dothideomycetous fungi are typically haploid, the reference H. werneckii strain has a diploid genome consisting of two subgenomes with a high level of heterozygosity. Results In order to explain the origin of the H. werneckii diploid genome we here report the genome sequencing of eleven strains isolated from different habitats and geographic locations. Comparison of nine diploid and two haploid strains showed that the reference genome was likely formed by hybridization between two haploids and not by endoreduplication as suggested previously. Results also support additional hybridization events in the evolutionary history of investigated strains, however exchange of genetic material in the species otherwise appears to be rare. Possible links between such unusual reproduction and the extremotolerance of H. werneckii remain to be investigated. Conclusions H. werneckii appears to be able to form persistent haploid as well as diploid strains, is capable of occasional hybridization between relatively heterozygous haploids, but is otherwise limited to clonal reproduction. The reported data and the first identification of haploid H. werneckii strains establish this species as a good model for studying the effects of ploidy and hybridization in an extremotolerant system unperturbed by frequent genetic recombination.

وصف الملف: electronic resource

Relation: http://link.springer.com/article/10.1186/s12864-018-4751-5; https://doaj.org/toc/1471-2164

URL الوصول: https://doaj.org/article/0e8cc166b32d46bcb5d092920bcc95b8

المؤلفون: Lande, Russell^{Aff1, Aff2}, Seehausen, Ole^{Aff2, Aff3}, van Alphen, Jacques J. M.^Aff2

المساهمون: Hendry, A. P., editor, Kinnison, M. T., editor

المصدر: Microevolution Rate, Pattern, Process. 8:435-443

المؤلفون: Paris Veltsos, Wen-Juan Ma

المساهمون: Biology, Cell Genetics

المصدر: Genes
Genes, Vol 12, Iss 483, p 483 (2021)

مصطلحات موضوعية: 0106 biological sciences, 0301 basic medicine, Male, lcsh:QH426-470, Evolution of sexual reproduction, sex determination, Review, Biology, telomere-restricted recombination, 010603 evolutionary biology, 01 natural sciences, Genome, heteromorphy, Evolution, Molecular, 03 medical and health sciences, Phylogenetics, Genetics, Animals, anurans, Genetics (clinical), Phylogeny, homomorphy, Sex Chromosomes, Chromosome, myr, Sex Determination Processes, sexually antagonistic selection, fountain of youth, lcsh:Genetics, 030104 developmental biology, Chromosome differentiation, Evolutionary biology, Sexual selection, Female, Anura, sex-determination turnover, Heterogametic sex, sex chromosome diversity

الوصف: Frogs are ideal organisms for studying sex chromosome evolution because of their diversity in sex chromosome differentiation and sex-determination systems. We review 222 anuran frogs, spanning ~220 Myr of divergence, with characterized sex chromosomes, and discuss their evolution, phylogenetic distribution and transitions between homomorphic and heteromorphic states, as well as between sex-determination systems. Most (~75%) anurans have homomorphic sex chromosomes, with XY systems being three times more common than ZW systems. Most remaining anurans (~25%) have heteromorphic sex chromosomes, with XY and ZW systems almost equally represented. There are Y-autosome fusions in 11 species, and no W-/Z-/X-autosome fusions are known. The phylogeny represents at least 19 transitions between sex-determination systems and at least 16 cases of independent evolution of heteromorphic sex chromosomes from homomorphy, the likely ancestral state. Five lineages mostly have heteromorphic sex chromosomes, which might have evolved due to demographic and sexual selection attributes of those lineages. Males do not recombine over most of their genome, regardless of which is the heterogametic sex. Nevertheless, telomere-restricted recombination between ZW chromosomes has evolved at least once. More comparative genomic studies are needed to understand the evolutionary trajectories of sex chromosomes among frog lineages, especially in the ZW systems.

URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a688b29a024b69844e6ad5c5891d7b4c
https://biblio.vub.ac.be/vubir/the-diversity-and-evolution-of-sex-chromosomes-in-frogs(935d1d89-379e-495d-beb9-94f764c0628b).html

المؤلفون: Jerneja Zupančič, Jason E. Stajich, Nina Gunde-Cimerman, Polona Zalar, Cene Gostinčar

المصدر: BMC Genomics
Gostincar, C; Stajich, JE; Zupancic, J; Zalar, P; & Gunde-Cimerman, N. (2018). Genomic evidence for intraspecific hybridization in a clonal and extremely halotolerant yeast. BMC GENOMICS, 19. doi: 10.1186/s12864-018-4751-5. UC Riverside: Retrieved from: http://www.escholarship.org/uc/item/2jb7q436
BMC Genomics, Vol 19, Iss 1, Pp 1-12 (2018)

مصطلحات موضوعية: 0106 biological sciences, 0301 basic medicine, lcsh:QH426-470, Black yeast, lcsh:Biotechnology, Halotolerance, Salt stress, Polyextremotolerance, 010603 evolutionary biology, 01 natural sciences, Genetic recombination, DNA sequencing, Whole genome duplication, Clonal reproduction, Loss of heterozygosity, 03 medical and health sciences, Ascomycota, Ploidy, lcsh:TP248.13-248.65, Genetics, Hybridization, Ecosystem, Phylogeny, biology, fungi, Restricted recombination, Genomics, biology.organism_classification, Diploidy, lcsh:Genetics, 030104 developmental biology, Hortaea werneckii, Hybridization, Genetic, Genome, Fungal, Research Article, Biotechnology, Reference genome

الوصف: Background The black yeast Hortaea werneckii (Dothideomycetes, Ascomycota) is one of the most extremely halotolerant fungi, capable of growth at NaCl concentrations close to saturation. Although dothideomycetous fungi are typically haploid, the reference H. werneckii strain has a diploid genome consisting of two subgenomes with a high level of heterozygosity. Results In order to explain the origin of the H. werneckii diploid genome we here report the genome sequencing of eleven strains isolated from different habitats and geographic locations. Comparison of nine diploid and two haploid strains showed that the reference genome was likely formed by hybridization between two haploids and not by endoreduplication as suggested previously. Results also support additional hybridization events in the evolutionary history of investigated strains, however exchange of genetic material in the species otherwise appears to be rare. Possible links between such unusual reproduction and the extremotolerance of H. werneckii remain to be investigated. Conclusions H. werneckii appears to be able to form persistent haploid as well as diploid strains, is capable of occasional hybridization between relatively heterozygous haploids, but is otherwise limited to clonal reproduction. The reported data and the first identification of haploid H. werneckii strains establish this species as a good model for studying the effects of ploidy and hybridization in an extremotolerant system unperturbed by frequent genetic recombination. Electronic supplementary material The online version of this article (10.1186/s12864-018-4751-5) contains supplementary material, which is available to authorized users.

وصف الملف: application/pdf

URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::da610d0e0c1059f244a48d5e64e8a018
https://doi.org/10.1186/s12864-018-4751-5

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المؤلفون: Kemppainen, Petri, 1979

مصطلحات موضوعية: Ecology, Ekologi, Speciation, Local adaptations, Ecotypes, Mitochondrial DNA, Introgression, Restricted recombination, Positive selection, Inversions, Chromosomal rearrangements

الوصف: The evolution of species takes in general very long time and different mechanisms are likely to operate during the various stages of this process. Accordingly speciation should be studied at different levels of species divergence. In this thesis I have studied ecological and genetical differentiation between two ecotypes of Littorina fabalis as well as between L. fabalis and L. obtusata - two closely related, directly developing, marine, intertidal gastropods. In L. fabalis size is about 25% larger in moderately exposed habitats compared to sheltered habitats and in this thesis I present data showing that this genetically inherited size different is maintained by an interaction of several selective forces, including life history optimisation, size selective crab predation, fucoid algae functioning as refuges from crab predation and wave-induced dislodgement. The two ecotypes of L. fabalis differ also in the protein arginine kinase (Ark) and a Randomly Amplified Polymorphic DNA (RAPD) locus and this linkage disequilibrium persists in locations where both ecotypes are present suggesting that recombination is strongly suppressed between Ark, the RAPD locus and one or several loci influencing size. Chromosomal rearrangement, in particular inversions are very effective in restricting recombination and if locally adapted alleles in at least two loci on the same chromosome occur in heterogeneous environments, an inversion may immediately protect these from being mixed up with alleles (introduced by migration) that are locally adapted for other microhabitats. This model predicts that differential selection on these alleles exist before an inversion appears and I have tested this by sequencing an intron of Ark. The SS-ecotype was nearly fixed for one haplotype while the diversity among LM-ecotypes was much higher supporting a scenario where a recently derived inversion (or other kind of chromosomal rearrangement) restricts recombination between Ark and one or several loci that influence size. In this thesis a novel method used for the sequencing of the Ark intron that does not require the cloning of each sample individually (which is both time consuming and expensive) is also presented. Littorina fabalis and L. obtusata are considered as well defined species with clear differences in ecology, morphology and nuclear DNA (allozymes) and with microsatellites I could show that hybridisation between these species has not been occurring at least during the last 10,000 years (they are easily identified in the field by both size and coloration). Despite this they show no consistent differences in the mitochondrial cyt-b gene, which could either be due to incomplete lineage sorting or introgression. The idea that mitochondrial DNA can be used as a barcode in species identification is attractive but has in recent years gained criticism because the nature of the mitochondrial molecule makes it specifically prone for introgression between species. Locally restricted mitochondrial introgressions are common among closely related species but the flat periwinkle case study in this thesis clearly shows that a lack of mitochondrial divergence can also exist throughout the whole distribution range for a geographically wide spread species (L. fabalis and L. obtusata occur sympatrically from Spain to Iceland and the White Sea, Russia)

URL الوصول: https://gup.ub.gu.se/publication/111396

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