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Setti PG, Deon GA, Zeni Dos Santos R, Goes CAG, Garnero ADV, Gunski RJ, de Oliveira EHC, Porto-Foresti F, de Freitas TRO, Silva FAO, Liehr T, Utsunomia R, Kretschmer R, de Bello Cioffi M. Evolution of bird sex chromosomes: a cytogenomic approach in Palaeognathae species. BMC Ecol Evol 2024; 24:51. [PMID: 38654159 PMCID: PMC11036779 DOI: 10.1186/s12862-024-02230-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 03/26/2024] [Indexed: 04/25/2024] Open
Abstract
BACKGROUND Different patterns of sex chromosome differentiation are seen in Palaeognathae birds, a lineage that includes the ratites (Struthioniformes, Rheiformes, Apterygiformes, Casuariiformes, and the sister group Tinamiformes). While some Tinamiform species have well-differentiated W chromosomes, both Z and W of all the flightless ratites are still morphologically undifferentiated. Here, we conducted a comprehensive analysis of the ZW differentiation in birds using a combination of cytogenetic, genomic, and bioinformatic approaches. The whole set of satDNAs from the emu (Dromaius novaehollandiae) was described and characterized. Furthermore, we examined the in situ locations of these satDNAs alongside several microsatellite repeats and carried out Comparative Genomic Hybridizations in two related species: the greater rhea (Rhea americana) and the tataupa tinamou (Crypturellus tataupa). RESULTS From the 24 satDNA families identified (which represent the greatest diversity of satDNAs ever uncovered in any bird species), only three of them were found to accumulate on the emu's sex chromosomes, with no discernible accumulation observed on the W chromosome. The W chromosomes of both the greater rhea and the emu did not exhibit a significant buildup of either C-positive heterochromatin or repetitive DNAs, indicating their large undifferentiation both at morphological and molecular levels. In contrast, the tataupa tinamou has a highly differentiated W chromosome that accumulates several DNA repeats. CONCLUSION The findings provide new information on the architecture of the avian genome and an inside look at the starting points of sex chromosome differentiation in birds.
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Affiliation(s)
- Príncia Grejo Setti
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, 13565-905, São Carlos, SP, Brazil
| | - Geize Aparecida Deon
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, 13565-905, São Carlos, SP, Brazil
| | | | | | - Analía Del Valle Garnero
- Campus São Gabriel, Universidade Federal do Pampa, 97307-020, São Gabriel, Rio Grande do Sul, Brazil
| | - Ricardo José Gunski
- Campus São Gabriel, Universidade Federal do Pampa, 97307-020, São Gabriel, Rio Grande do Sul, Brazil
| | - Edivaldo Herculano Corrêa de Oliveira
- Laboratório de Citogenômica e Mutagênese Ambiental, Seção de Meio Ambiente, Instituto Evandro Chagas, 67030-000, Ananindeua, PA, Brazil
- Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará, 66075-110, Belém, PA, Brazil
| | - Fábio Porto-Foresti
- Faculdade de Ciências, Universidade Estadual Paulista, 17033-360, Bauru, São Paulo, Brazil
| | | | - Fábio Augusto Oliveira Silva
- Laboratório de Citogenômica e Mutagênese Ambiental, Seção de Meio Ambiente, Instituto Evandro Chagas, 67030-000, Ananindeua, PA, Brazil
| | - Thomas Liehr
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, 07747, Jena, Germany.
| | - Ricardo Utsunomia
- Faculdade de Ciências, Universidade Estadual Paulista, 17033-360, Bauru, São Paulo, Brazil
| | - Rafael Kretschmer
- Departamento de Ecologia, Zoologia e Genética, Instituto de Biologia, Universidade Federal de Pelotas, 96.010-610, Pelotas, RS, Brazil
| | - Marcelo de Bello Cioffi
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, 13565-905, São Carlos, SP, Brazil
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2
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Cotter DJ, Webster TH, Wilson MA. Genomic and demographic processes differentially influence genetic variation across the human X chromosome. PLoS One 2023; 18:e0287609. [PMID: 37910456 PMCID: PMC10619814 DOI: 10.1371/journal.pone.0287609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 06/08/2023] [Indexed: 11/03/2023] Open
Abstract
Many forces influence genetic variation across the genome including mutation, recombination, selection, and demography. Increased mutation and recombination both lead to increases in genetic diversity in a region-specific manner, while complex demographic patterns shape patterns of diversity on a more global scale. While these processes act across the entire genome, the X chromosome is particularly interesting because it contains several distinct regions that are subject to different combinations and strengths of these forces: the pseudoautosomal regions (PARs) and the X-transposed region (XTR). The X chromosome thus can serve as a unique model for studying how genetic and demographic forces act in different contexts to shape patterns of observed variation. We therefore sought to explore diversity, divergence, and linkage disequilibrium in each region of the X chromosome using genomic data from 26 human populations. Across populations, we find that both diversity and substitution rate are consistently elevated in PAR1 and the XTR compared to the rest of the X chromosome. In contrast, linkage disequilibrium is lowest in PAR1, consistent with the high recombination rate in this region, and highest in the region of the X chromosome that does not recombine in males. However, linkage disequilibrium in the XTR is intermediate between PAR1 and the autosomes, and much lower than the non-recombining X. Finally, in addition to these global patterns, we also observed variation in ratios of X versus autosomal diversity consistent with population-specific evolutionary history as well. While our results were generally consistent with previous work, two unexpected observations emerged. First, our results suggest that the XTR does not behave like the rest of the recombining X and may need to be evaluated separately in future studies. Second, the different regions of the X chromosome appear to exhibit unique patterns of linked selection across different human populations. Together, our results highlight profound regional differences across the X chromosome, simultaneously making it an ideal system for exploring the action of evolutionary forces as well as necessitating its careful consideration and treatment in genomic analyses.
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Affiliation(s)
- Daniel J. Cotter
- Department of Genetics, Stanford University, Stanford, CA, United States of America
| | - Timothy H. Webster
- Department of Anthropology, University of Utah, Salt Lake City, UT, United States of America
- School of Life Sciences, Arizona State University, Tempe, AZ, United States of America
| | - Melissa A. Wilson
- School of Life Sciences, Arizona State University, Tempe, AZ, United States of America
- Center for Evolution and Medicine, Biodesign Institute, Arizona State University, Tempe, AZ, United States of America
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3
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Darolti I, Fong LJM, Sandkam BA, Metzger DCH, Mank JE. Sex chromosome heteromorphism and the Fast-X effect in poeciliids. Mol Ecol 2023; 32:4599-4609. [PMID: 37309716 DOI: 10.1111/mec.17048] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 05/29/2023] [Accepted: 05/31/2023] [Indexed: 06/14/2023]
Abstract
Fast-X evolution has been observed in a range of heteromorphic sex chromosomes. However, it remains unclear how early in the process of sex chromosome differentiation the Fast-X effect becomes detectible. Recently, we uncovered an extreme variation in sex chromosome heteromorphism across poeciliid fish species. The common guppy, Poecilia reticulata, Endler's guppy, P. wingei, swamp guppy, P. picta and para guppy, P. parae, appear to share the same XY system and exhibit a remarkable range of heteromorphism. Species outside this group lack this sex chromosome system. We combined analyses of sequence divergence and polymorphism data across poeciliids to investigate X chromosome evolution as a function of hemizygosity and reveal the causes for Fast-X effects. Consistent with the extent of Y degeneration in each species, we detect higher rates of divergence on the X relative to autosomes, a signal of Fast-X evolution, in P. picta and P. parae, species with high levels of X hemizygosity in males. In P. reticulata, which exhibits largely homomorphic sex chromosomes and little evidence of hemizygosity, we observe no change in the rate of evolution of X-linked relative to autosomal genes. In P. wingei, the species with intermediate sex chromosome differentiation, we see an increase in the rate of nonsynonymous substitutions on the older stratum of divergence only. We also use our comparative approach to test for the time of origin of the sex chromosomes in this clade. Taken together, our study reveals an important role of hemizygosity in Fast-X evolution.
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Affiliation(s)
- Iulia Darolti
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Lydia J M Fong
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Benjamin A Sandkam
- Department of Neurobiology and Behavior, Cornell University, Ithaca, New York, USA
| | - David C H Metzger
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Judith E Mank
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
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4
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Zhou Y, Zhan X, Jin J, Zhou L, Bergman J, Li X, Rousselle MMC, Belles MR, Zhao L, Fang M, Chen J, Fang Q, Kuderna L, Marques-Bonet T, Kitayama H, Hayakawa T, Yao YG, Yang H, Cooper DN, Qi X, Wu DD, Schierup MH, Zhang G. Eighty million years of rapid evolution of the primate Y chromosome. Nat Ecol Evol 2023; 7:1114-1130. [PMID: 37268856 DOI: 10.1038/s41559-022-01974-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 12/15/2022] [Indexed: 06/04/2023]
Abstract
The Y chromosome usually plays a critical role in determining male sex and comprises sequence classes that have experienced unique evolutionary trajectories. Here we generated 19 new primate sex chromosome assemblies, analysed them with 10 existing assemblies and report rapid evolution of the Y chromosome across primates. The pseudoautosomal boundary has shifted at least six times during primate evolution, leading to the formation of a Simiiformes-specific evolutionary stratum and to the independent start of young strata in Catarrhini and Platyrrhini. Different primate lineages experienced different rates of gene loss and structural and chromatin change on their Y chromosomes. Selection on several Y-linked genes has contributed to the evolution of male developmental traits across the primates. Additionally, lineage-specific expansions of ampliconic regions have further increased the diversification of the structure and gene composition of the Y chromosome. Overall, our comprehensive analysis has broadened our knowledge of the evolution of the primate Y chromosome.
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Affiliation(s)
| | | | | | - Long Zhou
- Centre for Evolutionary & Organismal Biology, and Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China
| | - Juraj Bergman
- Section for Ecoinformatics & Biodiversity, Department of Biology, Aarhus University, Aarhus C., Denmark
- Bioinformatics Research Centre, Aarhus University, Aarhus C., Denmark
| | - Xuemei Li
- BGI-Shenzhen, Shenzhen, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | | | | | - Lan Zhao
- College of Life Sciences, Northwest University, Xi'an, China
| | | | | | - Qi Fang
- BGI-Shenzhen, Shenzhen, China
| | - Lukas Kuderna
- Institute of Evolutionary Biology (UPF-CSIC), PRBB, Barcelona, Spain
| | - Tomas Marques-Bonet
- Institute of Evolutionary Biology (UPF-CSIC), PRBB, Barcelona, Spain
- Catalan Institution of Research and Advanced Studies (ICREA), Barcelona, Spain
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Haruka Kitayama
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
| | - Takashi Hayakawa
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan
- Japan Monkey Centre, Inuyama, Japan
| | - Yong-Gang Yao
- Kunming College of Life Science, University of the Chinese Academy of Sciences, Kunming, China
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China
- National Resource Center for Non-Human Primates, Kunming Primate Research Center, and National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Huanming Yang
- BGI-Shenzhen, Shenzhen, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
- James D. Watson Institute of Genome Sciences, Hangzhou, China
- Guangdong Provincial Academician Workstation of BGI Synthetic Genomics, BGI-Shenzhen, Shenzhen, China
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, China
| | - David N Cooper
- Institute of Medical Genetics, School of Medicine, Cardiff University, Cardiff, UK
| | - Xiaoguang Qi
- College of Life Sciences, Northwest University, Xi'an, China
| | - Dong-Dong Wu
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China
- National Resource Center for Non-Human Primates, Kunming Primate Research Center, and National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | | | - Guojie Zhang
- Centre for Evolutionary & Organismal Biology, and Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China.
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China.
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
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5
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Yazdi HP, Olito C, Kawakami T, Unneberg P, Schou MF, Cloete SWP, Hansson B, Cornwallis CK. The evolutionary maintenance of ancient recombining sex chromosomes in the ostrich. PLoS Genet 2023; 19:e1010801. [PMID: 37390104 DOI: 10.1371/journal.pgen.1010801] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 05/28/2023] [Indexed: 07/02/2023] Open
Abstract
Sex chromosomes have evolved repeatedly across the tree of life and often exhibit extreme size dimorphism due to genetic degeneration of the sex-limited chromosome (e.g. the W chromosome of some birds and Y chromosome of mammals). However, in some lineages, ancient sex-limited chromosomes have escaped degeneration. Here, we study the evolutionary maintenance of sex chromosomes in the ostrich (Struthio camelus), where the W remains 65% the size of the Z chromosome, despite being more than 100 million years old. Using genome-wide resequencing data, we show that the population scaled recombination rate of the pseudoautosomal region (PAR) is higher than similar sized autosomes and is correlated with pedigree-based recombination rate in the heterogametic females, but not homogametic males. Genetic variation within the sex-linked region (SLR) (π = 0.001) was significantly lower than in the PAR, consistent with recombination cessation. Conversely, genetic variation across the PAR (π = 0.0016) was similar to that of autosomes and dependent on local recombination rates, GC content and to a lesser extent, gene density. In particular, the region close to the SLR was as genetically diverse as autosomes, likely due to high recombination rates around the PAR boundary restricting genetic linkage with the SLR to only ~50Kb. The potential for alleles with antagonistic fitness effects in males and females to drive chromosome degeneration is therefore limited. While some regions of the PAR had divergent male-female allele frequencies, suggestive of sexually antagonistic alleles, coalescent simulations showed this was broadly consistent with neutral genetic processes. Our results indicate that the degeneration of the large and ancient sex chromosomes of the ostrich may have been slowed by high recombination in the female PAR, reducing the scope for the accumulation of sexually antagonistic variation to generate selection for recombination cessation.
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Affiliation(s)
| | - Colin Olito
- Department of Biology, Lund University, Lund, Sweden
| | - Takeshi Kawakami
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
- Embark Veterinary, Inc., Boston, Massachusetts, United States of America
| | - Per Unneberg
- Department of Cell and Molecular Biology, National Bioinformatics Infrastructure Sweden, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Mads F Schou
- Department of Biology, Lund University, Lund, Sweden
| | - Schalk W P Cloete
- Directorate Animal Sciences, Western Cape Department of Agriculture, Elsenburg, South Africa
- Department of Animal Sciences, Stellenbosch University, Matieland, South Africa
| | - Bengt Hansson
- Department of Biology, Lund University, Lund, Sweden
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6
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Wang Y, Cai X, Zhang Y, Hörandl E, Zhang Z, He L. The male-heterogametic sex determination system on chromosome 15 of Salix triandra and Salix arbutifolia reveals ancestral male heterogamety and subsequent turnover events in the genus Salix. Heredity (Edinb) 2023; 130:122-134. [PMID: 36593355 PMCID: PMC9981616 DOI: 10.1038/s41437-022-00586-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 12/08/2022] [Accepted: 12/09/2022] [Indexed: 01/03/2023] Open
Abstract
Dioecious Salix evolved more than 45 million years ago, but have homomorphic sex chromosomes, suggesting that turnover event(s) prevented major differentiation. Sex chromosome turnover events have been inferred in the sister genus Populus. The genus Salix includes two main clades, Salix and Vetrix, with several previously studied Vetrix clade species having female-heterogametic (ZW) or male-heterogametic (XY) sex-determining systems (SDSs) on chromosome 15, while three Salix clade species have XY SDSs on chromosome 7. We here studied two basal taxa of the Vetrix clade, S. arbutifolia and S. triandra using S. purpurea as the reference genome. Analyses of whole genome resequencing data for genome-wide associations (GWAS) with the sexes and genetic differentiation between the sexes (FST values) showed that both species have male heterogamety with a sex-determining locus on chromosome 15, suggesting an early turnover event within the Vetrix clade, perhaps promoted by sexually antagonistic or (and) sex-ratio selection. Changepoint analysis based on FST values identified small sex-linked regions of ~3.33 Mb and ~2.80 Mb in S. arbutifolia and S. triandra, respectively. The SDS of S. arbutifolia was consistent with recent results that used its own genome as reference. Ancestral state reconstruction of SDS suggests that at least two turnover events occurred in Salix.
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Affiliation(s)
- Yi Wang
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai, 201602, China
| | - Xinjie Cai
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yue Zhang
- Shenyang Arboretum, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Elvira Hörandl
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), University of Goettingen, Göttingen, Germany
| | - Zhixiang Zhang
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China.
| | - Li He
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai, 201602, China.
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7
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Burley JT, Orzechowski SCM, Sin SYW, Edwards SV. Whole-genome phylogeography of the blue-faced honeyeater (Entomyzon cyanotis) and discovery and characterization of a neo-Z chromosome. Mol Ecol 2023; 32:1248-1270. [PMID: 35797346 DOI: 10.1111/mec.16604] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 06/22/2022] [Accepted: 07/04/2022] [Indexed: 11/28/2022]
Abstract
Whole-genome surveys of genetic diversity and geographic variation often yield unexpected discoveries of novel structural variation, which long-read DNA sequencing can help clarify. Here, we report on whole-genome phylogeography of a bird exhibiting classic vicariant geographies across Australia and New Guinea, the blue-faced honeyeater (Entomyzon cyanotis), and the discovery and characterization of a novel neo-Z chromosome by long-read sequencing. Using short-read genome-wide SNPs, we inferred population divergence events within E. cyanotis across the Carpentarian and other biogeographic barriers during the Pleistocene (~0.3-1.7 Ma). Evidence for introgression between nonsister populations supports a hypothesis of reticulate evolution around a triad of dynamic barriers around Pleistocene Lake Carpentaria between Australia and New Guinea. During this phylogeographic survey, we discovered a large (134 Mbp) neo-Z chromosome and we explored its diversity, divergence and introgression landscape. We show that, as in some sylvioid passerine birds, a fusion occurred between chromosome 5 and the Z chromosome to form a neo-Z chromosome; and in E. cyanotis, the ancestral pseudoautosomal region (PAR) appears nonrecombinant between Z and W, along with most of the fused chromosome 5. The added recombination-suppressed portion of the neo-Z (~37.2 Mbp) displays reduced diversity and faster population genetic differentiation compared with the ancestral-Z. Yet, the new PAR (~17.4 Mbp) shows elevated diversity and reduced differentiation compared to autosomes, potentially resulting from introgression. In our case, long-read sequencing helped clarify the genomic landscape of population divergence on autosomes and sex chromosomes in a species where prior knowledge of genome structure was still incomplete.
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Affiliation(s)
- John T Burley
- Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA.,Department of Evolutionary Biology, Evolutionary Biology Centre (EBC), Uppsala University, Uppsala, Sweden.,Department of Ecology Evolution and Organismal Biology, Brown University, Providence, Rhode Island, USA.,Institute at Brown for Environment and Society, Brown University, Providence, Rhode Island, USA
| | | | - Simon Yung Wa Sin
- Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA.,School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Scott V Edwards
- Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA
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8
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Heterochiasmy and Sex Chromosome Evolution in Silene. Genes (Basel) 2023; 14:genes14030543. [PMID: 36980816 PMCID: PMC10048291 DOI: 10.3390/genes14030543] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 02/17/2023] [Accepted: 02/21/2023] [Indexed: 02/24/2023] Open
Abstract
The evolution of a non-recombining sex-specific region is a key step in sex chromosome evolution. Suppression of recombination between the (proto-) X- and Y-chromosomes in male meiosis creates a non-recombining Y-linked region (NRY), while the X-chromosome continues to recombine in females. Lack of recombination in the NRY defines its main properties—genetic degeneration and accumulation of repetitive DNA, making X and Y chromosomes very different from each other. How and why recombination suppression on sex chromosomes evolves remains controversial. A strong difference in recombination rates between the sexes (heterochiasmy) can facilitate or even cause recombination suppression. In the extreme case—complete lack of recombination in the heterogametic sex (achiasmy)—the entire sex-specific chromosome is automatically non-recombining. In this study, I analyse sex-specific recombination rates in a dioecious plant Silene latifolia (Caryophyllaceae), which evolved separate sexes and sex chromosomes ~11 million years ago. I reconstruct high-density RNAseq-based genetic maps including over five thousand genic markers for the two sexes separately. The comparison of the male and female maps reveals only modest heterochiasmy across the genome, with the exception of the sex chromosomes, where recombination is suppressed in males. This indicates that heterochiasmy likely played only a minor, if any, role in NRY evolution in S. latifolia, as recombination suppression is specific to NRY rather than to the entire genome in males. Other mechanisms such as structural rearrangements and/or epigenetic modifications were likely involved, and comparative genome analysis and genetic mapping in multiple Silene species will help to shed light on the mechanism(s) of recombination suppression that led to the evolution of sex chromosomes.
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9
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Han W, Liu L, Wang J, Wei H, Li Y, Zhang L, Guo Z, Li Y, Liu T, Zeng Q, Xing Q, Shu Y, Wang T, Yang Y, Zhang M, Li R, Yu J, Pu Z, Lv J, Lian S, Hu J, Hu X, Bao Z, Bao L, Zhang L, Wang S. Ancient homomorphy of molluscan sex chromosomes sustained by reversible sex-biased genes and sex determiner translocation. Nat Ecol Evol 2022; 6:1891-1906. [PMID: 36280781 DOI: 10.1038/s41559-022-01898-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 09/05/2022] [Indexed: 12/15/2022]
Abstract
Contrary to classic theory prediction, sex-chromosome homomorphy is prevalent in the animal kingdom but it is unclear how ancient homomorphic sex chromosomes avoid chromosome-scale degeneration. Molluscs constitute the second largest, Precambrian-originated animal phylum and have ancient, uncharacterized homomorphic sex chromosomes. Here, we profile eight genomes of the bivalve mollusc family of Pectinidae in a phylogenetic context and show 350 million years sex-chromosome homomorphy, which is the oldest known sex-chromosome homomorphy in the animal kingdom, far exceeding the ages of well-known heteromorphic sex chromosomes such as 130-200 million years in mammals, birds and flies. The long-term undifferentiation of molluscan sex chromosomes is potentially sustained by the unexpected intertwined regulation of reversible sex-biased genes, together with the lack of sexual dimorphism and occasional sex chromosome turnover. The pleiotropic constraint of regulation of reversible sex-biased genes is widely present in ancient homomorphic sex chromosomes and might be resolved in heteromorphic sex chromosomes through gene duplication followed by subfunctionalization. The evolutionary dynamics of sex chromosomes suggest a mechanism for 'inheritance' turnover of sex-determining genes that is mediated by translocation of a sex-determining enhancer. On the basis of these findings, we propose an evolutionary model for the long-term preservation of homomorphic sex chromosomes.
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Affiliation(s)
- Wentao Han
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Liangjie Liu
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Jing Wang
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Huilan Wei
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Yuli Li
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Lijing Zhang
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Zhenyi Guo
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Yajuan Li
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Tian Liu
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Qifan Zeng
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- Key Laboratory of Tropical Aquatic Germplasm of Hainan Province, Sanya Oceanographic Institution, Ocean University of China, Sanya, China
| | - Qiang Xing
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Ya Shu
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Tong Wang
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Yaxin Yang
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Meiwei Zhang
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Ruojiao Li
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Jiachen Yu
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Zhongqi Pu
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Jia Lv
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Shanshan Lian
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Jingjie Hu
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Key Laboratory of Tropical Aquatic Germplasm of Hainan Province, Sanya Oceanographic Institution, Ocean University of China, Sanya, China
| | - Xiaoli Hu
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Zhenmin Bao
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- Key Laboratory of Tropical Aquatic Germplasm of Hainan Province, Sanya Oceanographic Institution, Ocean University of China, Sanya, China
| | - Lisui Bao
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao, China.
| | - Lingling Zhang
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China.
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
| | - Shi Wang
- Sars-Fang Centre & MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China.
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
- Key Laboratory of Tropical Aquatic Germplasm of Hainan Province, Sanya Oceanographic Institution, Ocean University of China, Sanya, China.
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10
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Bergman J, Schierup MH. Evolutionary dynamics of pseudoautosomal region 1 in humans and great apes. Genome Biol 2022; 23:215. [PMID: 36253794 PMCID: PMC9575207 DOI: 10.1186/s13059-022-02784-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 09/30/2022] [Indexed: 12/03/2022] Open
Abstract
Background The pseudoautosomal region 1 (PAR1) is a 2.7 Mb telomeric region of human sex chromosomes. PAR1 has a crucial role in ensuring proper segregation of sex chromosomes during male meiosis, exposing it to extreme recombination and mutation processes. We investigate PAR1 evolution using population genomic datasets of extant humans, eight populations of great apes, and two archaic human genome sequences. Results We find that PAR1 is fast evolving and closer to evolutionary nucleotide equilibrium than autosomal telomeres. We detect a difference between substitution patterns and extant diversity in PAR1, mainly driven by the conflict between strong mutation and recombination-associated fixation bias at CpG sites. We detect excess C-to-G mutations in PAR1 of all great apes, specific to the mutagenic effect of male recombination. Despite recent evidence for Y chromosome introgression from humans into Neanderthals, we find that the Neanderthal PAR1 retained similarity to the Denisovan sequence. We find differences between substitution spectra of these archaics suggesting rapid evolution of PAR1 in recent hominin history. Frequency analysis of alleles segregating in females and males provided no evidence for recent sexual antagonism in this region. We study repeat content and double-strand break hotspot regions in PAR1 and find that they may play roles in ensuring the obligate X-Y recombination event during male meiosis. Conclusions Our study provides an unprecedented quantification of population genetic forces governing PAR1 biology across extant and extinct hominids. PAR1 evolutionary dynamics are predominantly governed by recombination processes with a strong impact on mutation patterns across all species. Supplementary Information The online version contains supplementary material available at 10.1186/s13059-022-02784-x.
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Affiliation(s)
- Juraj Bergman
- Bioinformatics Research Centre, Aarhus University, DK-8000, Aarhus C, Denmark.
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11
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Capron C, Januel L, Vieville G, Jaillard S, Kuentz P, Salaun G, Nadeau G, Clement P, Brechard MP, Herve B, Dupont JM, Gruchy N, Chambon P, Abdelhedi F, Dahlen E, Vago P, Harbuz R, Plotton I, Coutton C, Belaud-Rotureau MA, Schluth-Bolard C, Vialard F. Evidence for high breakpoint variability in 46, XX, SRY-positive testicular disorder and frequent ARSE deletion that may be associated with short stature. Andrology 2022; 10:1625-1631. [PMID: 36026611 DOI: 10.1111/andr.13279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 08/19/2022] [Accepted: 08/19/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND The translocation of SRY onto one of the two X chromosomes results in a 46,XX testicular disorder of sex development; this is supposedly due to non-allelic homologous recombination between the protein kinase X gene (PRKX) and the inverted protein kinase Y pseudogene (PRKY). Although 46,XX SRY-positive men are infertile, the literature data indicate that some of these individuals are of short stature (relative to the general population). We sought to determine whether short stature was linked to additional, more complex chromosomal rearrangements. METHODS Twelve laboratories gathered detailed clinical, anthropomorphic, cytogenetic and genetic data (including chromosome microarray (CMA) data) on patients with 46,XX SRY-positive male syndrome. RESULTS SRY was present (suggesting a der(X)t(X;Y)) in 34 of the 38 cases (89.5%). When considering only the 20 patients with CMA data, we identified several chromosomal rearrangements and breakpoints - especially on the X chromosome. In the five cases for whom the X chromosome breakpoint was located in the pseudoautosomal (PAR) region, there was partial duplication of the derivate X chromosome. In contrast, in the 15 cases for whom the breakpoint was located downstream of the pseudoautosomal region, part of the derivate X chromosome had been deleted (included the arylsulfatase E (ARSE) gene in 11 patients). For patients with vs. without ARSE deletion, the mean height was respectively 167.7 ± 4.5 and 173.1 ± 4.0 cm; this difference was not statistically significant (p = 0.1005). CONCLUSION Although 46,XX SRY-positive male syndromes were mainly due to imbalanced crossover between the X and Y chromosome during meiosis, the breakpoints differed markedly from one patient to another (especially on the X chromosome); this suggests the presence of a replication-based mechanism for recombination between non-homologous sequences. In some patients, the translocation of SRY to the X chromosome was associated with ARSE gene deletion, which might have led to short stature. With a view to explaining this disorder of sex development, whole exome sequencing could be suggested for SRY-negative patients. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Céline Capron
- Département de Génétique, CHI de Poissy St Germain en Laye, Poissy, France
| | - Louis Januel
- Service de Génétique, Hospices Civils de Lyon, Lyon, France
| | - Gaëlle Vieville
- Département de Génétique et Procréation, Hôpital Couple Enfant, CHU Grenoble, Grenoble Cedex, 38043, France.,INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Université Grenoble Alpes, Grenoble, France
| | - Sylvie Jaillard
- Cytogénétique et Biologie cellulaire, CHU de Rennes, Rennes, France.,IRSET - INSERM UMR1085 - Equipe Physiologie et physiopathologie du tractus uro-génital, Faculté de Médecine, Université de Rennes 1, Rennes, France
| | - Paul Kuentz
- Oncobiologie Génétique Bioinformatique, PCBio, CHU Besançon, Besançon, France
| | - Gaëlle Salaun
- CHU Clermont-Ferrand, Cytogénétique Médicale, Clermont-Ferrand, France
| | - Gwenaël Nadeau
- Laboratoire de Cytogénétique, CH de Chambéry, Chambéry, France
| | | | | | - Bérénice Herve
- Département de Génétique, CHI de Poissy St Germain en Laye, Poissy, France
| | | | - Nicolas Gruchy
- Service de Génétique - CHU de Caen - Site Clémenceau, Caen, France.,EA7450, Université Caen Normandie, Caen, France
| | - Pascal Chambon
- UNIROUEN, Inserm U1245, Université de Normandie, Rouen, France.,Département de Génétique, CHU Rouen, Rouen, France
| | - Fatma Abdelhedi
- Service de Génétique Médicale, CHU Hédi Chaker, Sfax, Tunisie.,Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Sfax, Tunisie
| | - Eric Dahlen
- Oncobiologie Génétique Bioinformatique, PCBio, CHU Besançon, Besançon, France
| | - Philippe Vago
- CHU Clermont-Ferrand, Cytogénétique Médicale, Clermont-Ferrand, France
| | - Radu Harbuz
- Département de Génétique et Procréation, Hôpital Couple Enfant, CHU Grenoble, Grenoble Cedex, 38043, France
| | - Ingrid Plotton
- Service de Médecine de la Reproduction, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France.,Laboratoire d'hormonologie et endocrinologie Moléculaire, Hospices Civils de Lyon, Bron, France.,Unité INSERM 1208, Université Lyon 1, Lyon, France
| | - Charles Coutton
- Département de Génétique et Procréation, Hôpital Couple Enfant, CHU Grenoble, Grenoble Cedex, 38043, France.,INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Université Grenoble Alpes, Grenoble, France
| | - Marc-Antoine Belaud-Rotureau
- Cytogénétique et Biologie cellulaire, CHU de Rennes, Rennes, France.,IRSET - INSERM UMR1085 - Equipe Physiologie et physiopathologie du tractus uro-génital, Faculté de Médecine, Université de Rennes 1, Rennes, France
| | - Caroline Schluth-Bolard
- Service de Génétique, Hospices Civils de Lyon, Lyon, France.,Institut Neuromyogène, Equipe Métabolisme énergétique et développement neuronal, CNRS UMR 5310, INSERM U1217, Université Lyon 1, Lyon, France
| | - François Vialard
- Département de Génétique, CHI de Poissy St Germain en Laye, Poissy, France.,UMR-BREED, INRAE, ENVA, UVSQ, UFR SVS, Montigny le Bretonneux, France
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12
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Kim KW, De-Kayne R, Gordon IJ, Omufwoko KS, Martins DJ, Ffrench-Constant R, Martin SH. Stepwise evolution of a butterfly supergene via duplication and inversion. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210207. [PMID: 35694743 PMCID: PMC9189502 DOI: 10.1098/rstb.2021.0207] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Supergenes maintain adaptive clusters of alleles in the face of genetic mixing. Although usually attributed to inversions, supergenes can be complex, and reconstructing the precise processes that led to recombination suppression and their timing is challenging. We investigated the origin of the BC supergene, which controls variation in warning coloration in the African monarch butterfly, Danaus chrysippus. By generating chromosome-scale assemblies for all three alleles, we identified multiple structural differences. Most strikingly, we find that a region of more than 1 million bp underwent several segmental duplications at least 7.5 Ma. The resulting duplicated fragments appear to have triggered four inversions in surrounding parts of the chromosome, resulting in stepwise growth of the region of suppressed recombination. Phylogenies for the inversions are incongruent with the species tree and suggest that structural polymorphisms have persisted for at least 4.1 Myr. In addition to the role of duplications in triggering inversions, our results suggest a previously undescribed mechanism of recombination suppression through independent losses of divergent duplicated tracts. Overall, our findings add support for a stepwise model of supergene evolution involving a variety of structural changes. This article is part of the theme issue ‘Genomic architecture of supergenes: causes and evolutionary consequences’.
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Affiliation(s)
- Kang-Wook Kim
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
| | - Rishi De-Kayne
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
| | - Ian J Gordon
- Centre of Excellence in Biodiversity and Natural Resource Management, University of Rwanda, Huye Campus, Huye, Rwanda
| | | | - Dino J Martins
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, USA.,Mpala Research Centre, Nanyuki, Kenya
| | | | - Simon H Martin
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
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13
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Dagilis AJ, Sardell JM, Josephson MP, Su Y, Kirkpatrick M, Peichel CL. Searching for signatures of sexually antagonistic selection on stickleback sex chromosomes. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210205. [PMID: 35694749 PMCID: PMC9189504 DOI: 10.1098/rstb.2021.0205] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Intralocus sexually antagonistic selection occurs when an allele is beneficial to one sex but detrimental to the other. This form of selection is thought to be key to the evolution of sex chromosomes but is hard to detect. Here we perform an analysis of phased young sex chromosomes to look for signals of sexually antagonistic selection in the Japan Sea stickleback (Gasterosteus nipponicus). Phasing allows us to date the suppression of recombination on the sex chromosome and provides unprecedented resolution to identify sexually antagonistic selection in the recombining region of the chromosome. We identify four windows with elevated divergence between the X and Y in the recombining region, all in or very near genes associated with phenotypes potentially under sexually antagonistic selection in humans. We are unable, however, to rule out the alternative hypothesis that the peaks of divergence result from demographic effects. Thus, although sexually antagonistic selection is a key hypothesis for the formation of supergenes on sex chromosomes, it remains challenging to detect. This article is part of the theme issue ‘Genomic architecture of supergenes: causes and evolutionary consequences’.
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Affiliation(s)
- Andrius J Dagilis
- Department of Integrative Biology, University of Texas, Austin TX 78712, USA.,Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Jason M Sardell
- Department of Integrative Biology, University of Texas, Austin TX 78712, USA
| | - Matthew P Josephson
- Division of Evolutionary Ecology, Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland
| | - Yiheng Su
- Department of Computer Science, University of Texas, Austin TX 78712, USA
| | - Mark Kirkpatrick
- Department of Integrative Biology, University of Texas, Austin TX 78712, USA
| | - Catherine L Peichel
- Division of Evolutionary Ecology, Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland
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14
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Xu X, Wang Y, Wang C, Guo G, Yu X, Dai Y, Liu Y, Wei G, He X, Jin G, Zhang Z, Guan Q, Pain A, Wang S, Zhang W, Young ND, Gasser RB, McManus DP, Cao J, Zhou Q, Zhang Q. Chromosome-level genome assembly defines female-biased genes associated with sex determination and differentiation in the human blood fluke Schistosoma japonicum. Mol Ecol Resour 2022; 23:205-221. [PMID: 35844053 DOI: 10.1111/1755-0998.13689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 07/05/2022] [Accepted: 07/11/2022] [Indexed: 12/01/2022]
Abstract
Schistosomiasis is a neglected tropical disease of humans caused by blood flukes of the genus Schistosoma, the only dioecious parasitic flatworm. Although aspects of sex determination, differentiation and reproduction have been studied in some Schistosoma species, almost nothing is known for Schistosoma japonicum, the causative agent of schistosomiasis japonica. This mainly reflects the lack of high-quality genomic and transcriptomic resources for this species. As current genomes for S. japonicum are highly fragmented, we assembled and report a chromosome-level reference genome (seven autosomes, the Z-chromosome and partial W-chromosome), achieving a substantially enhanced gene annotation. Utilizing this genome, we discovered that the sex chromosomes of S. japonicum and its congener S. mansoni independently suppressed recombination during evolution, forming five and two evolutionary strata, respectively. By exploring the W-chromosome and sex-specific transcriptomes, we identified 35 W-linked genes and 257 female-preferentially transcribed genes (FTGs) from our chromosomal assembly and uncovered a signature for sex determination and differentiation in S. japonicum. These FTGs clustering within autosomes or the Z-chromosome exhibit a highly dynamic transcription profile during the pairing of female and male schistosomula, thereby representing a critical phase for the maturation of the female worms and suggesting distinct layers of regulatory control of gene transcription at this development stage. Collectively, these data provide a valuable resource for further functional genomic characterization of S. japonicum, shed light on the evolution of sex chromosomes in this highly virulent human blood fluke, and provide a pathway to identify novel targets for development of intervention tools against schistosomiasis.
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Affiliation(s)
- Xindong Xu
- Laboratory of Molecular Parasitology, Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Tongji Hospital, and Clinical Center for Brain and Spinal Cord Research School of Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Yifeng Wang
- MOE Laboratory of Biosystems Homeostasis and Protection and Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, China
| | - Changhong Wang
- Laboratory of Molecular Parasitology, Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Tongji Hospital, and Clinical Center for Brain and Spinal Cord Research School of Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Gangqiang Guo
- Laboratory of Molecular Parasitology, Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Tongji Hospital, and Clinical Center for Brain and Spinal Cord Research School of Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Xinyu Yu
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China
| | - Yang Dai
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China
| | - Yaobao Liu
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China
| | - Guiying Wei
- Laboratory of Molecular Parasitology, Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Tongji Hospital, and Clinical Center for Brain and Spinal Cord Research School of Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Xiaohui He
- Laboratory of Molecular Parasitology, Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Tongji Hospital, and Clinical Center for Brain and Spinal Cord Research School of Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Ge Jin
- Novogene Bioinformatics Institute, Beijing, China
| | - Ziqiu Zhang
- Novogene Bioinformatics Institute, Beijing, China
| | - Qingtian Guan
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Arnab Pain
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Shengyue Wang
- National Research Center for Translational Medicine, State Key Laboratory of Medical Genomics, Ruijin Hospital Affiliated to Shanghai Jiao Tong University (SJTU) School of Medicine, Shanghai, China
| | - Wenbao Zhang
- State Key Laboratory of Pathogenesis, Prevention and Treatment of High Incidence Diseases in Central Asia, Clinical Medical Research Institute, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Neil D Young
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Robin B Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Donald P McManus
- Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Jun Cao
- National Health Commission Key Laboratory of Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, China.,Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Qi Zhou
- MOE Laboratory of Biosystems Homeostasis and Protection and Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, China.,Department of Neuroscience and Developmental Biology, University of Vienna, Vienna, Austria.,Center for Reproductive Medicine, the Second Affiliated Hospital School of Medicine and Life Sciences Institute, Zhejiang University, Hangzhou, China
| | - Qingfeng Zhang
- Laboratory of Molecular Parasitology, Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Tongji Hospital, and Clinical Center for Brain and Spinal Cord Research School of Medicine, School of Medicine, Tongji University, Shanghai, China
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15
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Filatov DA. Recent expansion of the non-recombining sex-linked region on Silene latifolia sex chromosomes. J Evol Biol 2022; 35:1696-1708. [PMID: 35834179 PMCID: PMC10083954 DOI: 10.1111/jeb.14063] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 06/19/2022] [Accepted: 06/21/2022] [Indexed: 11/27/2022]
Abstract
Evolution of a non-recombining sex-specific region on the Y (or W) chromosome (NRY) is a key step in sex chromosome evolution, but how recombination suppression evolves is not well understood. Studies in many different organisms indicated that NRY evolution often involves several expansion steps. Why such NRY expansions occur remains unclear, although it is though that they are likely driven by sexually antagonistic selection. This paper describes a recent NRY expansion due to shift of the pseudoautosomal boundary on the sex chromosomes of a dioecious plant Silene latifolia. The shift resulted in inclusion of at least 16 pseudoautosomal genes into the NRY. This region is pseudoautosomal in closely related Silene dioica and Silene diclinis, indicating that the NRY expansion occurred in S. latifolia after it speciated from the other species ~120 thousand years ago. As S. latifolia and S. dioica actively hybridise across Europe, interspecific gene flow could blur the PAR boundary in these species. The pseudoautosomal genes have significantly elevated genetic diversity (π ~ 3% at synonymous sites), which is consistent with balancing selection maintaining diversity in this region. The recent shift of the PAR boundary in S. latifolia offers an opportunity to study the process of on-going NRY expansion.
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16
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Santos C, Mendes T, Antunes A. The genes from the pseudoautosomal region 1 (PAR1) of the mammalian sex chromosomes: Synteny, phylogeny and selection. Genomics 2022; 114:110419. [PMID: 35753589 DOI: 10.1016/j.ygeno.2022.110419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 06/10/2022] [Accepted: 06/20/2022] [Indexed: 11/04/2022]
Abstract
Sex chromosomes recombine restrictly in their homologous area, the pseudoautosomal region (PAR), represented by PAR1 and PAR2, which behave like an autosome in both pairing and recombination. The PAR1, common to most of the eutherian mammals, is located at the terminus of the sex chromosomes short arm and exhibit recombination rates ~20 times higher than the autosomes. Here, we assessed the interspecific evolutionary genomic dynamics of 15 genes of the PAR1 across 41 mammalian genera (representing six orders). The strong negative selection detected in most of the assessed groups reinforces the presence of evolutionary constraints, imposed by the important function of the PAR1 genes. Indeed, mutations in these genes are associated with various diseases in humans, including stature problems (Klinefelter Syndrome), leukemia and mental diseases. Yet, a few genes exhibiting positive selection (ω-value >1) were depicted in Rodentia (ASMT and ZBED1) and Primates (CRLF2 and CSF2RA). Rodents have the smallest described PAR1, while that of simian primates/humans underwent a 3 to 5 fold size reduction. The assessment of the PAR1 genes synteny revealed differences among the mammalian species, especially in the Rodentia order where chromosomic translocations from the sex chromosomes to the autosomes were observed. Such syntenic changes may be an evidence of the rapid evolution in rodents, as previous referred in other papers, also depicted by their increased branch lengths in the phylogenetic analyses. Concluding, we suggest that genome migration is an important factor influencing the evolution of mammals and may result in changes of the selective pressures operating on the genome.
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Affiliation(s)
- Carla Santos
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Avenida General Norton de Matos, s/n, 4450-208 Porto, Portugal; Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Portugal
| | - Tito Mendes
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Avenida General Norton de Matos, s/n, 4450-208 Porto, Portugal
| | - Agostinho Antunes
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Avenida General Norton de Matos, s/n, 4450-208 Porto, Portugal; Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal.
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17
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Delph LF, Brown KE, Ríos LD, Kelly JK. Sex‐specific natural selection on SNPs in
Silene latifolia. Evol Lett 2022; 6:308-318. [PMID: 35937470 PMCID: PMC9346077 DOI: 10.1002/evl3.283] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 02/24/2022] [Accepted: 03/13/2022] [Indexed: 01/15/2023] Open
Affiliation(s)
- Lynda F. Delph
- Department of Biology Indiana University Bloomington Indiana USA
| | - Keely E. Brown
- Department of Ecology and Evolutionary Biology University of Kansas Lawrence Kansas USA
| | - Luis Diego Ríos
- Department of Biology Indiana University Bloomington Indiana USA
| | - John K. Kelly
- Department of Ecology and Evolutionary Biology University of Kansas Lawrence Kansas USA
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18
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Why not Y naught. Heredity (Edinb) 2022; 129:75-78. [PMID: 35581478 PMCID: PMC9338309 DOI: 10.1038/s41437-022-00543-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 05/02/2022] [Accepted: 05/05/2022] [Indexed: 11/12/2022] Open
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19
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Ponnikas S, Sigeman H, Lundberg M, Hansson B. Extreme variation in recombination rate and genetic diversity along the Sylvioidea neo-sex chromosome. Mol Ecol 2022; 31:3566-3583. [PMID: 35578784 PMCID: PMC9327509 DOI: 10.1111/mec.16532] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 04/13/2022] [Accepted: 05/04/2022] [Indexed: 12/03/2022]
Abstract
Recombination strongly impacts sequence evolution by affecting the extent of linkage and the efficiency of selection. Here, we study recombination over the Z chromosome in great reed warblers (Acrocephalus arundinaceus) using pedigree‐based linkage mapping. This species has extended Z and W chromosomes (“neo‐sex chromosomes”) formed by a fusion between a part of chromosome 4A and the ancestral sex chromosomes, which provides a unique opportunity to assess recombination and sequence evolution in sex‐linked regions of different ages. We assembled an 87.54 Mbp and 90.19 cM large Z with a small pseudoautosomal region (0.89 Mbp) at one end and the fused Chr4A‐part at the other end of the chromosome. A prominent feature in our data was an extreme variation in male recombination rate along Z with high values at both chromosome ends, but an apparent lack of recombination over a substantial central section, covering 78% of the chromosome. The nonrecombining region showed a drastic loss of genetic diversity and accumulation of repeats compared to the recombining parts. Thus, our data emphasize a key role of recombination in affecting local levels of polymorphism. Nonetheless, the evolutionary rate of genes (dN/dS) did not differ between high and low recombining regions, suggesting that the efficiency of selection on protein‐coding sequences can be maintained also at very low levels of recombination. Finally, the Chr4A‐derived part showed a similar recombination rate as the part of the ancestral Z that did recombine, but its sequence characteristics reflected both its previous autosomal, and current Z‐linked, recombination patterns.
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Affiliation(s)
- Suvi Ponnikas
- Department of Biology, Lund University, Lund, Sweden.,Ecology and Genetics Research Unit, University of Oulu, Oulu, Finland
| | - Hanna Sigeman
- Department of Biology, Lund University, Lund, Sweden
| | - Max Lundberg
- Department of Biology, Lund University, Lund, Sweden
| | - Bengt Hansson
- Department of Biology, Lund University, Lund, Sweden
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20
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Xue R, Tang Q, Zhang Y, Xie M, Li C, Wang S, Yang H. Integrative Analyses of Genes Associated With Otologic Disorders in Turner Syndrome. Front Genet 2022; 13:799783. [PMID: 35273637 PMCID: PMC8902304 DOI: 10.3389/fgene.2022.799783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 02/08/2022] [Indexed: 12/02/2022] Open
Abstract
Background: Loss or partial loss of one X chromosome induces Turner syndrome (TS) in females, causing major medical concerns, including otologic disorders. However, the underlying genetic pathophysiology of otologic disorders in TS is mostly unclear. Methods: Ear-related genes of TS (TSEs) were identified by analyzing differentially expressed genes (DEGs) in two Gene Expression Omnibus (GEO)-derived expression profiles and ear-genes in the Comparative Toxicogenomic Database (CTD). Subsequently, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Disease Ontology (DO) analyses; Gene Set Enrichment Analysis (GSEA); and Gene Set Variation Analysis (GSVA) were adopted to study biological functions. Moreover, hub genes within the TSEs were identified by assessing protein-protein interaction (PPI), gene-microRNA, and gene-transcription factor (TF) networks. Drug-Gene Interaction Database (DGIdb) analysis was performed to predict molecular drugs for TS. Furthermore, three machine-learning analysis outcomes were comprehensively compared to explore optimal biomarkers of otologic disorders in TS. Finally, immune cell infiltration was analyzed. Results: The TSEs included 30 significantly upregulated genes and 14 significantly downregulated genes. Enrichment analyses suggested that TSEs play crucial roles in inflammatory responses, phospholipid and glycerolipid metabolism, transcriptional processes, and epigenetic processes, such as histone acetylation, and their importance for inner ear development. Subsequently, we described three hub genes in the PPI network and confirmed their involvement in Wnt/β-catenin signaling pathway and immune cell regulation and roles in maintaining normal auditory function. We also constructed gene-microRNA and gene-TF networks. A novel biomarker (SLC25A6) of the pathogenesis of otologic disorders in TS was identified by comprehensive comparisons of three machine-learning analyses with the best predictive performance. Potential therapeutic agents in TS were predicted using the DGIdb. Immune cell infiltration analysis showed that TSEs are related to immune-infiltrating cells. Conclusion: Overall, our findings have deepened the understanding of the pathophysiology of otologic disorders in TS and made contributions to present a promising biomarker and treatment targets for in-depth research.
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Affiliation(s)
- Ruoyan Xue
- Department of Otolaryngology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Qi Tang
- Department of Otolaryngology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yongli Zhang
- Department of Otolaryngology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Mengyao Xie
- Department of Otolaryngology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Chen Li
- Department of Otolaryngology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Shu Wang
- Department of Otolaryngology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hua Yang
- Department of Otolaryngology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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21
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Hansen CCR, Westfall KM, Pálsson S. Evaluation of four methods to identify the homozygotic sex chromosome in small populations. BMC Genomics 2022; 23:160. [PMID: 35209843 PMCID: PMC8867824 DOI: 10.1186/s12864-022-08393-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 02/15/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Whole genomes are commonly assembled into a collection of scaffolds and often lack annotations of autosomes, sex chromosomes, and organelle genomes (i.e., mitochondrial and chloroplast). As these chromosome types differ in effective population size and can have highly disparate evolutionary histories, it is imperative to take this information into account when analysing genomic variation. Here we assessed the accuracy of four methods for identifying the homogametic sex chromosome in a small population using two whole genome sequences (WGS) and 133 RAD sequences of white-tailed eagles (Haliaeetus albicilla): i) difference in read depth per scaffold in a male and a female, ii) heterozygosity per scaffold in a male and a female, iii) mapping to the reference genome of a related species (chicken) with annotated sex chromosomes, and iv) analysis of SNP-loadings from a principal components analysis (PCA), based on the low-depth RADseq data. RESULTS The best performing approach was the reference mapping (method iii), which identified 98.12% of the expected homogametic sex chromosome (Z). Read depth per scaffold (method i) identified 86.41% of the homogametic sex chromosome with few false positives. SNP-loading scores (method iv) identified 78.6% of the Z-chromosome and had a false positive discovery rate of more than 10%. Heterozygosity per scaffold (method ii) did not provide clear results due to a lack of diversity in both the Z and autosomal chromosomes, and potential interference from the heterogametic sex chromosome (W). The evaluation of these methods also revealed 10 Mb of putative PAR and gametologous regions. CONCLUSION Identification of the homogametic sex chromosome in a small population is best accomplished by reference mapping or examining differences in read depth between sexes.
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Affiliation(s)
| | - Kristen M Westfall
- Department of Life and Environmental Sciences, University of Iceland, Reykjavik, Iceland.,Current: Fisheries and Oceans Canada, Pacific Biological Station, Nanaimo, BC, Canada
| | - Snæbjörn Pálsson
- Department of Life and Environmental Sciences, University of Iceland, Reykjavik, Iceland
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22
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Astro V, Alowaysi M, Fiacco E, Saera-Vila A, Cardona-Londoño KJ, Aiese Cigliano R, Adamo A. Pseudoautosomal Region 1 Overdosage Affects the Global Transcriptome in iPSCs From Patients With Klinefelter Syndrome and High-Grade X Chromosome Aneuploidies. Front Cell Dev Biol 2022; 9:801597. [PMID: 35186953 PMCID: PMC8850648 DOI: 10.3389/fcell.2021.801597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 12/28/2021] [Indexed: 01/19/2023] Open
Abstract
Klinefelter syndrome (KS) is the most prevalent aneuploidy in males and is characterized by a 47,XXY karyotype. Less frequently, higher grade sex chromosome aneuploidies (HGAs) can also occur. Here, using a paradigmatic cohort of KS and HGA induced pluripotent stem cells (iPSCs) carrying 49,XXXXY, 48,XXXY, and 47,XXY karyotypes, we identified the genes within the pseudoautosomal region 1 (PAR1) as the most susceptible to dosage-dependent transcriptional dysregulation and therefore potentially responsible for the progressively worsening phenotype in higher grade X aneuploidies. By contrast, the biallelically expressed non-PAR escape genes displayed high interclonal and interpatient variability in iPSCs and differentiated derivatives, suggesting that these genes could be associated with variable KS traits. By interrogating KS and HGA iPSCs at the single-cell resolution we showed that PAR1 and non-PAR escape genes are not only resilient to the X-inactive specific transcript (XIST)-mediated inactivation but also that their transcriptional regulation is disjointed from the absolute XIST expression level. Finally, we explored the transcriptional effects of X chromosome overdosage on autosomes and identified the nuclear respiratory factor 1 (NRF1) as a key regulator of the zinc finger protein X-linked (ZFX). Our study provides the first evidence of an X-dosage-sensitive autosomal transcription factor regulating an X-linked gene in low- and high-grade X aneuploidies.
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Affiliation(s)
- Veronica Astro
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Maryam Alowaysi
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Elisabetta Fiacco
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | | | - Kelly J. Cardona-Londoño
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | | | - Antonio Adamo
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- *Correspondence: Antonio Adamo,
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23
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Dynamic Patterns of Sex Chromosome Evolution in Neognath Birds: Many Independent Barriers to Recombination at the ATP5F1A Locus. BIRDS 2022. [DOI: 10.3390/birds3010004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Avian sex chromosomes evolved after the divergence of birds and crocodilians from their common ancestor, so they are younger than the better-studied chromosomes of mammals. It has long been recognized that there may have been several stages to the evolution of avian sex chromosomes. For example, the CHD1 undergoes recombination in paleognaths but not neognaths. Genome assemblies have suggested that there may be variation in the timing of barriers to recombination among Neognathae, but there remains little understanding of the extent of this variability. Here, we look at partial sequences of ATP5F1A, which is on the avian Z and W chromosomes. It is known that recombination of this gene has independently ceased in Galliformes, Anseriformes, and at least five neoavian orders, but whether there are other independent cessations of recombination among Neoaves is not understood. We analyzed a combination of data extracted from published chromosomal-level genomes with data collected using PCR and cloning to identify Z and W copies in 22 orders. Our results suggest that there may be at least 19 independent cessations of recombination within Neognathae, and 3 clades that may still be undergoing recombination (or have only recently ceased recombination). Analyses of ATP5F1A protein sequences revealed an increased amino acid substitution rate for W chromosome gametologs, suggesting relaxed purifying selection on the W chromosome. Supporting this hypothesis, we found that the increased substitution rate was particularly pronounced for buried residues, which are expected to be more strongly constrained by purifying selection. This highlights the dynamic nature of avian sex chromosomes, and that this level of variation among clades means they should be a good system to understand sex chromosome evolution.
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24
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Ramos L, Antunes A. Decoding sex: Elucidating sex determination and how high-quality genome assemblies are untangling the evolutionary dynamics of sex chromosomes. Genomics 2022; 114:110277. [PMID: 35104609 DOI: 10.1016/j.ygeno.2022.110277] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 12/22/2021] [Accepted: 01/26/2022] [Indexed: 11/28/2022]
Abstract
Sexual reproduction is a diverse and widespread process. In gonochoristic species, the differentiation of sexes occurs through diverse mechanisms, influenced by environmental and genetic factors. In most vertebrates, a master-switch gene is responsible for triggering a sex determination network. However, only a few genes have acquired master-switch functions, and this process is associated with the evolution of sex-chromosomes, which have a significant influence in evolution. Additionally, their highly repetitive regions impose challenges for high-quality sequencing, even using high-throughput, state-of-the-art techniques. Here, we review the mechanisms involved in sex determination and their role in the evolution of species, particularly vertebrates, focusing on sex chromosomes and the challenges involved in sequencing these genomic elements. We also address the improvements provided by the growth of sequencing projects, by generating a massive number of near-gapless, telomere-to-telomere, chromosome-level, phased assemblies, increasing the number and quality of sex-chromosome sequences available for further studies.
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Affiliation(s)
- Luana Ramos
- CIIMAR/CIMAR, Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450-208 Porto, Portugal; Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal
| | - Agostinho Antunes
- CIIMAR/CIMAR, Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450-208 Porto, Portugal; Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal.
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25
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Ruzicka F, Connallon T. An unbiased test reveals no enrichment of sexually antagonistic polymorphisms on the human X chromosome. Proc Biol Sci 2022; 289:20212314. [PMID: 35078366 PMCID: PMC8790371 DOI: 10.1098/rspb.2021.2314] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Mutations with beneficial effects in one sex can have deleterious effects in the other. Such 'sexually antagonistic' (SA) variants contribute to variation in life-history traits and overall fitness, yet their genomic distribution is poorly resolved. Theory predicts that SA variants could be enriched on the X chromosome or autosomes, yet current empirical tests face two formidable challenges: (i) identifying SA selection in genomic data is difficult; and (ii) metrics of SA variation show persistent biases towards the X, even when SA variants are randomly distributed across the genome. Here, we present an unbiased test of the theory that SA variants are enriched on the X. We first develop models for reproductive FST-a metric for quantifying sex-differential (including SA) effects of genetic variants on lifetime reproductive success-that control for X-linked biases. Comparing data from approximately 250 000 UK Biobank individuals to our models, we find FST elevations consistent with both X-linked and autosomal SA polymorphisms affecting reproductive success in humans. However, the extent of FST elevations does not differ from a model in which SA polymorphisms are randomly distributed across the genome. We argue that the polygenic nature of SA variation, along with sex asymmetries in SA effects, might render X-linked enrichment of SA polymorphisms unlikely.
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Affiliation(s)
- Filip Ruzicka
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Tim Connallon
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
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26
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Fukami M, Fujisawa Y, Ono H, Jinno T, Ogata T. Human Spermatogenesis Tolerates Massive Size Reduction of the Pseudoautosomal Region. Genome Biol Evol 2021; 12:1961-1964. [PMID: 32785664 PMCID: PMC7608489 DOI: 10.1093/gbe/evaa168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/05/2020] [Indexed: 01/21/2023] Open
Abstract
Mammalian male meiosis requires homologous recombination between the X and Y chromosomes. In humans, such recombination occurs exclusively in the short arm pseudoautosomal region (PAR1) of 2.699 Mb in size. Although it is known that complete deletion of PAR1 causes spermatogenic arrest, no studies have addressed to what extent male meiosis tolerates PAR1 size reduction. Here, we report two families in which PAR1 partial deletions were transmitted from fathers to their offspring. Cytogenetic analyses revealed that a ∼400-kb segment at the centromeric end of PAR1, which accounts for only 14.8% of normal PAR1 and 0.26% and 0.68% of the X and Y chromosomes, respectively, is sufficient to mediate sex chromosomal recombination during spermatogenesis. These results highlight the extreme recombinogenic activity of human PAR1. Our data, in conjunction with previous findings from animal studies, indicate that the minimal size requirement of mammalian PARs to maintain male fertility is fairly small.
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Affiliation(s)
- Maki Fukami
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Yasuko Fujisawa
- Department of Pediatrics, Hamamatsu University School of Medicine, Japan
| | - Hiroyuki Ono
- Department of Pediatrics, Hamamatsu University School of Medicine, Japan
| | - Tomoko Jinno
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Tsutomu Ogata
- Department of Pediatrics, Hamamatsu University School of Medicine, Japan
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27
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Chromosome-Level Genome Assemblies Expand Capabilities of Genomics for Conservation Biology. Genes (Basel) 2021; 12:genes12091336. [PMID: 34573318 PMCID: PMC8466942 DOI: 10.3390/genes12091336] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/20/2021] [Accepted: 08/25/2021] [Indexed: 11/26/2022] Open
Abstract
Genome assemblies are in the process of becoming an increasingly important tool for understanding genetic diversity in threatened species. Unfortunately, due to limited budgets typical for the area of conservation biology, genome assemblies of threatened species, when available, tend to be highly fragmented, represented by tens of thousands of scaffolds not assigned to chromosomal locations. The recent advent of high-throughput chromosome conformation capture (Hi-C) enables more contiguous assemblies containing scaffolds spanning the length of entire chromosomes for little additional cost. These inexpensive contiguous assemblies can be generated using Hi-C scaffolding of existing short-read draft assemblies, where N50 of the draft contigs is larger than 0.1% of the estimated genome size and can greatly improve analyses and facilitate visualization of genome-wide features including distribution of genetic diversity in markers along chromosomes or chromosome-length scaffolds. We compared distribution of genetic diversity along chromosomes of eight mammalian species, including six listed as threatened by IUCN, where both draft genome assemblies and newer chromosome-level assemblies were available. The chromosome-level assemblies showed marked improvement in localization and visualization of genetic diversity, especially where the distribution of low heterozygosity across the genomes of threatened species was not uniform.
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28
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Xenophontos A, Seidlitz J, Liu S, Clasen LS, Blumenthal JD, Giedd JN, Alexander-Bloch A, Raznahan A. Altered Sex Chromosome Dosage Induces Coordinated Shifts in Cortical Anatomy and Anatomical Covariance. Cereb Cortex 2021; 30:2215-2228. [PMID: 31828307 DOI: 10.1093/cercor/bhz235] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Sex chromosome dosage (SCD) variation increases risk for neuropsychiatric impairment, which may reflect direct SCD effects on brain organization. Here, we 1) map cumulative X- and Y-chromosome dosage effects on regional cortical thickness (CT) and investigate potential functional implications of these effects using Neurosynth, 2) test if this map is organized by patterns of CT covariance that are evident in health, and 3) characterize SCD effects on CT covariance itself. We modeled SCD effects on CT and CT covariance for 308 equally sized regions of the cortical sheet using structural neuroimaging data from 301 individuals with varying numbers of sex chromosomes (169 euploid, 132 aneuploid). Mounting SCD increased CT in the rostral frontal cortex and decreased CT in the lateral temporal cortex, bilaterally. Regions targeted by SCD were associated with social functioning, language processing, and comprehension. Cortical regions with a similar degree of SCD-sensitivity showed heightened CT covariance in health. Finally, greater SCD also increased covariance among regions similarly affected by SCD. Our study both 1) develops novel methods for comparing typical and disease-related structural covariance networks in the brain and 2) uses these techniques to resolve and identify organizing principles for SCD effects on regional cortical anatomy and anatomical covariance.
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Affiliation(s)
- Anastasia Xenophontos
- Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20892, USA
| | - Jakob Seidlitz
- Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20892, USA.,Department of Psychiatry, University of Cambridge, Cambridge CB2 1TN, UK
| | - Siyuan Liu
- Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20892, USA
| | - Liv S Clasen
- Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20892, USA
| | - Jonathan D Blumenthal
- Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20892, USA
| | - Jay N Giedd
- Department of Psychiatry, University of California, La Jolla, CA 92093, USA
| | - Aaron Alexander-Bloch
- Department of Child and Adolescent Psychiatry and Behavioral Science, Children's Hospital of Philadelphia, Philadelphia, PA 19104.,Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104
| | - Armin Raznahan
- Developmental Neurogenomics Unit, Human Genetics Branch, National Institute of Mental Health, Bethesda, MD 20892, USA
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29
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Hartmann FE, Ament-Velásquez SL, Vogan AA, Gautier V, Le Prieur S, Berramdane M, Snirc A, Johannesson H, Grognet P, Malagnac F, Silar P, Giraud T. Size Variation of the Nonrecombining Region on the Mating-Type Chromosomes in the Fungal Podospora anserina Species Complex. Mol Biol Evol 2021; 38:2475-2492. [PMID: 33555341 PMCID: PMC8136517 DOI: 10.1093/molbev/msab040] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Sex chromosomes often carry large nonrecombining regions that can extend progressively over time, generating evolutionary strata of sequence divergence. However, some sex chromosomes display an incomplete suppression of recombination. Large genomic regions without recombination and evolutionary strata have also been documented around fungal mating-type loci, but have been studied in only a few fungal systems. In the model fungus Podospora anserina (Ascomycota, Sordariomycetes), the reference S strain lacks recombination across a 0.8-Mb region around the mating-type locus. The lack of recombination in this region ensures that nuclei of opposite mating types are packaged into a single ascospore (pseudohomothallic lifecycle). We found evidence for a lack of recombination around the mating-type locus in the genomes of ten P. anserina strains and six closely related pseudohomothallic Podospora species. Importantly, the size of the nonrecombining region differed between strains and species, as indicated by the heterozygosity levels around the mating-type locus and experimental selfing. The nonrecombining region is probably labile and polymorphic, differing in size and precise location within and between species, resulting in occasional, but infrequent, recombination at a given base pair. This view is also supported by the low divergence between mating types, and the lack of strong linkage disequilibrium, chromosomal rearrangements, transspecific polymorphism and genomic degeneration. We found a pattern suggestive of evolutionary strata in P. pseudocomata. The observed heterozygosity levels indicate low but nonnull outcrossing rates in nature in these pseudohomothallic fungi. This study adds to our understanding of mating-type chromosome evolution and its relationship to mating systems.
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Affiliation(s)
- Fanny E Hartmann
- Ecologie Systématique Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | | | - Aaron A Vogan
- Organismal Biology, Uppsala University, Uppsala, Sweden
| | - Valérie Gautier
- Laboratoire Interdisciplinaire des Energies de Demain, Université de Paris, Paris, France
| | - Stephanie Le Prieur
- Ecologie Systématique Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Myriam Berramdane
- Ecologie Systématique Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | - Alodie Snirc
- Ecologie Systématique Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
| | | | - Pierre Grognet
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Fabienne Malagnac
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Philippe Silar
- Laboratoire Interdisciplinaire des Energies de Demain, Université de Paris, Paris, France
| | - Tatiana Giraud
- Ecologie Systématique Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
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30
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Kuhl H, Guiguen Y, Höhne C, Kreuz E, Du K, Klopp C, Lopez-Roques C, Yebra-Pimentel ES, Ciorpac M, Gessner J, Holostenco D, Kleiner W, Kohlmann K, Lamatsch DK, Prokopov D, Bestin A, Bonpunt E, Debeuf B, Haffray P, Morvezen R, Patrice P, Suciu R, Dirks R, Wuertz S, Kloas W, Schartl M, Stöck M. A 180 Myr-old female-specific genome region in sturgeon reveals the oldest known vertebrate sex determining system with undifferentiated sex chromosomes. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200089. [PMID: 34247507 PMCID: PMC8273502 DOI: 10.1098/rstb.2020.0089] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Several hypotheses explain the prevalence of undifferentiated sex chromosomes in poikilothermic vertebrates. Turnovers change the master sex determination gene, the sex chromosome or the sex determination system (e.g. XY to WZ). Jumping master genes stay main triggers but translocate to other chromosomes. Occasional recombination (e.g. in sex-reversed females) prevents sex chromosome degeneration. Recent research has uncovered conserved heteromorphic or even homomorphic sex chromosomes in several clades of non-avian and non-mammalian vertebrates. Sex determination in sturgeons (Acipenseridae) has been a long-standing basic biological question, linked to economical demands by the caviar-producing aquaculture. Here, we report the discovery of a sex-specific sequence from sterlet (Acipenser ruthenus). Using chromosome-scale assemblies and pool-sequencing, we first identified an approximately 16 kb female-specific region. We developed a PCR-genotyping test, yielding female-specific products in six species, spanning the entire phylogeny with the most divergent extant lineages (A. sturio, A. oxyrinchus versus A. ruthenus, Huso huso), stemming from an ancient tetraploidization. Similar results were obtained in two octoploid species (A. gueldenstaedtii, A. baerii). Conservation of a female-specific sequence for a long period, representing 180 Myr of sturgeon evolution, and across at least one polyploidization event, raises many interesting biological questions. We discuss a conserved undifferentiated sex chromosome system with a ZZ/ZW-mode of sex determination and potential alternatives. This article is part of the theme issue ‘Challenging the paradigm in sex chromosome evolution: empirical and theoretical insights with a focus on vertebrates (Part I)’.
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Affiliation(s)
- Heiner Kuhl
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301 and 310, 12587 Berlin, Germany
| | | | - Christin Höhne
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301 and 310, 12587 Berlin, Germany
| | - Eva Kreuz
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301 and 310, 12587 Berlin, Germany
| | - Kang Du
- Developmental Biochemistry, Biocenter, University of Würzburg, 97074 Würzburg, Germany.,The Xiphophorus Genetic Stock Center, Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA
| | - Christophe Klopp
- SIGENAE, Plate-forme Bio-informatique Genotoul, Mathématiques et Informatique Appliquées de Toulouse, INRAe, 31326 Castanet-Tolosan, France
| | | | | | - Mitica Ciorpac
- Danube Delta National Institute for Research and Development, Tulcea 820112, Romania.,Genetic Improvement Laboratory, Research Station for Cattle Breeding Dancu - Iasi (SCDCB Dancu), Academy of Agricultural and Forestry Sciences 'Gheorghe Ionescu-Sisesti', Iasi-Ungheni Street, No. 9, Holboca, Iași county 707252, Romania
| | - Jörn Gessner
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301 and 310, 12587 Berlin, Germany
| | - Daniela Holostenco
- Danube Delta National Institute for Research and Development, Tulcea 820112, Romania
| | - Wibke Kleiner
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301 and 310, 12587 Berlin, Germany
| | - Klaus Kohlmann
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301 and 310, 12587 Berlin, Germany
| | - Dunja K Lamatsch
- Research Department for Limnology, University of Innsbruck, A-5310 Mondsee, Austria
| | - Dmitry Prokopov
- Institute of Molecular and Cellular Biology, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Anastasia Bestin
- SYSAAF, Station INRAE-LPGP, Campus de Beaulieu, 35042 Rennes cedex, France
| | | | - Bastien Debeuf
- SCEA Sturgeon, 29 rue du Carillon, 17240 Saint Fort sur Gironde, France
| | - Pierrick Haffray
- SYSAAF, Station INRAE-LPGP, Campus de Beaulieu, 35042 Rennes cedex, France
| | - Romain Morvezen
- SYSAAF, Station INRAE-LPGP, Campus de Beaulieu, 35042 Rennes cedex, France
| | - Pierre Patrice
- SYSAAF, Station INRAE-LPGP, Campus de Beaulieu, 35042 Rennes cedex, France
| | - Radu Suciu
- Danube Delta National Institute for Research and Development, Tulcea 820112, Romania
| | - Ron Dirks
- Future Genomics Technologies B.V., Sylviusweg 74, 2333 BD, Leiden, The Netherlands
| | - Sven Wuertz
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301 and 310, 12587 Berlin, Germany
| | - Werner Kloas
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301 and 310, 12587 Berlin, Germany
| | - Manfred Schartl
- Developmental Biochemistry, Biocenter, University of Würzburg, 97074 Würzburg, Germany.,The Xiphophorus Genetic Stock Center, Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA
| | - Matthias Stöck
- Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301 and 310, 12587 Berlin, Germany
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31
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Warling A, Yavi M, Clasen LS, Blumenthal JD, Lalonde FM, Raznahan A, Liu S. Sex Chromosome Dosage Effects on White Matter Structure in the Human Brain. Cereb Cortex 2021; 31:5339-5353. [PMID: 34117759 DOI: 10.1093/cercor/bhab162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 04/29/2021] [Accepted: 05/18/2021] [Indexed: 11/14/2022] Open
Abstract
Sex chromosome aneuploidies, a group of neurogenetic conditions characterized by aberrant sex chromosome dosage (SCD), are associated with increased risks for psychopathology as well as alterations in gray matter structure. However, we still lack a comprehensive understanding of potential SCD-associated changes in white matter structure, or knowledge of how these changes might relate to known alterations in gray matter anatomy. Thus, here, we use voxel-based morphometry on structural neuroimaging data to provide the first comprehensive maps of regional white matter volume (WMV) changes across individuals with varying SCD (n = 306). We show that mounting X- and Y-chromosome dosage are both associated with widespread WMV decreases, including in cortical, subcortical, and cerebellar tracts, as well as WMV increases in the genu of the corpus callosum and posterior thalamic radiation. We also correlate X- and Y-chromosome-linked WMV changes in certain regions to measures of internalizing and externalizing psychopathology. Finally, we demonstrate that SCD-driven WMV changes show a coordinated coupling with SCD-driven gray matter volume changes. These findings represent the most complete maps of X- and Y-chromosome effects on human white matter to date, and show how such changes connect to psychopathological symptoms and gray matter anatomy.
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Affiliation(s)
- Allysa Warling
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mani Yavi
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Liv S Clasen
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jonathan D Blumenthal
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - François M Lalonde
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Armin Raznahan
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Siyuan Liu
- Section on Developmental Neurogenomics, Human Genetics Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
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32
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Chae T, Harkess A, Moore RC. Sex-linked gene expression and the emergence of hermaphrodites in Carica papaya. AMERICAN JOURNAL OF BOTANY 2021; 108:1029-1041. [PMID: 34156700 DOI: 10.1002/ajb2.1689] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 02/08/2021] [Indexed: 06/13/2023]
Abstract
PREMISE One evolutionary path from hermaphroditism to dioecy is via a gynodioecious intermediate. The evolution of dioecy may also coincide with the formation of sex chromosomes that possess sex-determining loci that are physically linked in a region of suppressed recombination. Dioecious papaya (Carica papaya) has an XY chromosome system, where the presence of a Y chromosome determines maleness. However, in cultivation, papaya is gynodioecious, due to the conversion of the male Y chromosome to a hermaphroditic Yh chromosome during its domestication. METHODS We investigated gene expression linked to the X, Y, and Yh chromosomes at different floral developmental stages to identify differentially expressed genes that may be involved in the sexual transition of males to hermaphrodites. RESULTS We identified 309 sex-biased genes found on the sex chromosomes, most of which are found in the pseudoautosomal regions. Female (XX) expression in the sex-determining region was almost double that of X-linked expression in males (XY) and hermaphrodites (XYh ), which rules out dosage compensation for most sex-linked genes; although, an analysis of hemizygous X-linked loci found evidence of partial dosage compensation. Furthermore, we identified a candidate gene associated with sex determination and the transition to hermaphroditism, a homolog of the MADS-box protein SHORT VEGETATIVE PHASE. CONCLUSIONS We identified a pattern of partial dosage compensation for hemizygous genes located in the papaya sex-determining region. Furthermore, we propose that loss-of-expression of the Y-linked SHORT VEGETATIVE PHASE homolog facilitated the transition from males to hermaphrodites in papaya.
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Affiliation(s)
- Taylor Chae
- Department of Biology, Miami University, Oxford, OH
| | - Alex Harkess
- Department of Crop, Soil, and Environmental Sciences, Auburn University, Auburn, AL
- HudsonAlpha Institute for Biotechnology, Huntsville, AL
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33
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Meisel RP. The maintenance of polygenic sex determination depends on the dominance of fitness effects which are predictive of the role of sexual antagonism. G3 (BETHESDA, MD.) 2021; 11:6261074. [PMID: 33930135 PMCID: PMC8496315 DOI: 10.1093/g3journal/jkab149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/23/2021] [Indexed: 12/18/2022]
Abstract
In species with polygenic sex determination (PSD), multiple male- and female-determining loci on different proto-sex chromosomes segregate as polymorphisms within populations. The extent to which these polymorphisms are at stable equilibria is not yet resolved. Previous work demonstrated that PSD is most likely to be maintained as a stable polymorphism when the proto-sex chromosomes have opposite (sexually antagonistic) fitness effects in males and females. However, these models usually consider PSD systems with only two proto-sex chromosomes, or they do not broadly consider the dominance of the alleles under selection. To address these shortcomings, I used forward population genetic simulations to identify selection pressures that can maintain PSD under different dominance scenarios in a system with more than two proto-sex chromosomes (modeled after the house fly). I found that overdominant fitness effects of male-determining proto-Y chromosomes are more likely to maintain PSD than dominant, recessive, or additive fitness effects. The overdominant fitness effects that maintain PSD tend to have proto-Y chromosomes with sexually antagonistic effects (male-beneficial and female-detrimental). In contrast, dominant fitness effects that maintain PSD tend to have sexually antagonistic multi-chromosomal genotypes, but the individual proto-sex chromosomes do not have sexually antagonistic effects. These results demonstrate that sexual antagonism can be an emergent property of the multi-chromosome genotype without individual sexually antagonistic chromosomes. My results further illustrate how the dominance of fitness effects has consequences for both the likelihood that PSD will be maintained as well as the role sexually antagonistic selection is expected to play in maintaining the polymorphism.
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Affiliation(s)
- Richard P Meisel
- Department of Biology and Biochemistry, University of Houston, Houston, TX 77204, USA
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34
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Flintham EO, Savolainen V, Mullon C. Dispersal Alters the Nature and Scope of Sexually Antagonistic Variation. Am Nat 2021; 197:543-559. [PMID: 33908829 DOI: 10.1086/713739] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractIntralocus sexual conflict, or sexual antagonism, occurs when alleles have opposing fitness effects in the two sexes. Previous theory suggests that sexual antagonism is a driver of genetic variation by generating balancing selection. However, most of these studies assume that populations are well mixed, neglecting the effects of spatial subdivision. Here, we use mathematical modeling to show that limited dispersal changes evolution at sexually antagonistic autosomal and X-linked loci as a result of inbreeding and sex-specific kin competition. We find that if the sexes disperse at different rates, kin competition within the philopatric sex biases intralocus conflict in favor of the more dispersive sex. Furthermore, kin competition diminishes the strength of balancing selection relative to genetic drift, reducing genetic variation in small subdivided populations. Meanwhile, by decreasing heterozygosity, inbreeding reduces the scope for sexually antagonistic polymorphism due to nonadditive allelic effects, and this occurs to a greater extent on the X chromosome than autosomes. Overall, our results indicate that spatial structure is a relevant factor in predicting where sexually antagonistic alleles might be observed. We suggest that sex-specific dispersal ecology and demography can contribute to interspecific and intragenomic variation in sexual antagonism.
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35
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Monteiro B, Arenas M, Prata MJ, Amorim A. Evolutionary dynamics of the human pseudoautosomal regions. PLoS Genet 2021; 17:e1009532. [PMID: 33872316 PMCID: PMC8084340 DOI: 10.1371/journal.pgen.1009532] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 04/29/2021] [Accepted: 04/06/2021] [Indexed: 01/19/2023] Open
Abstract
Recombination between the X and Y human sex chromosomes is limited to the two pseudoautosomal regions (PARs) that present quite distinct evolutionary origins. Despite the crucial importance for male meiosis, genetic diversity patterns and evolutionary dynamics of these regions are poorly understood. In the present study, we analyzed and compared the genetic diversity of the PAR regions using publicly available genomic sequences encompassing both PAR1 and PAR2. Comparisons were performed through allele diversities, linkage disequilibrium status and recombination frequencies within and between X and Y chromosomes. In agreement with previous studies, we confirmed the role of PAR1 as a male-specific recombination hotspot, but also observed similar characteristic patterns of diversity in both regions although male recombination occurs at PAR2 to a much lower extent (at least one recombination event at PAR1 and in ≈1% in normal male meioses at PAR2). Furthermore, we demonstrate that both PARs harbor significantly different allele frequencies between X and Y chromosomes, which could support that recombination is not sufficient to homogenize the pseudoautosomal gene pool or is counterbalanced by other evolutionary forces. Nevertheless, the observed patterns of diversity are not entirely explainable by sexually antagonistic selection. A better understanding of such processes requires new data from intergenerational transmission studies of PARs, which would be decisive on the elucidation of PARs evolution and their role in male-driven heterosomal aneuploidies.
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Affiliation(s)
- Bruno Monteiro
- Institute of Investigation and Innovation in Health (i3S). University of Porto, Porto, Portugal
- Institute of Molecular Pathology and Immunology (IPATIMUP), University of Porto, Porto, Portugal
| | - Miguel Arenas
- Department of Biochemistry, Genetics and Immunology, University of Vigo, Vigo, Spain
- CINBIO (Biomedical Research Centre), University of Vigo, Vigo, Spain
| | - Maria João Prata
- Institute of Investigation and Innovation in Health (i3S). University of Porto, Porto, Portugal
- Institute of Molecular Pathology and Immunology (IPATIMUP), University of Porto, Porto, Portugal
- Faculty of Sciences, University of Porto, Porto, Portugal
- * E-mail:
| | - António Amorim
- Institute of Investigation and Innovation in Health (i3S). University of Porto, Porto, Portugal
- Institute of Molecular Pathology and Immunology (IPATIMUP), University of Porto, Porto, Portugal
- Faculty of Sciences, University of Porto, Porto, Portugal
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36
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Cormier F, Martin G, Vignes H, Lachman L, Cornet D, Faure Y, Maledon E, Mournet P, Arnau G, Chaïr H. Genetic control of flowering in greater yam (Dioscorea alata L.). BMC PLANT BIOLOGY 2021; 21:163. [PMID: 33794780 PMCID: PMC8015048 DOI: 10.1186/s12870-021-02941-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 03/25/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Greater yam (Dioscorea alata L.) is a major tropical and subtropical staple crop cultivated for its starchy tubers. Breeding of this dioecious species is hampered by its erratic flowering, yet little is currently known on the genetic determinism of its sexual reproduction. RESULT Here we used a genome-wide association approach and identified a major genetic barrier to reproduction in yam on chromosome 1, as represented by two candidate genes. A deleterious effect on male fitness could be hypothesized considering the involvement of these two genes in male reproduction and the low frequency of this non-flowering dominant allele within the male genepool. We also extended the hypothesis of a XX/XY sex-determination system located on chromosome 6 in D. alata to encompass most of the species diversity. Moreover, a kompetitive allele-specific PCR (KASPar) marker was designed and validated that enables accurate cultivar sex estimation. The reconstruction of chromosome 6 associated with the detection of highly putative structural variations confirmed the possible involvement of a major part of the chromosome. CONCLUSION The findings of this study, combined with proper estimation of accession ploidy levels to avoid endosperm incompatibility issues, could facilitate the design of future promising parental combinations in D. alata breeding programs. Moreover, the discovery of this genetic barrier to reproduction opens new avenues for gaining insight into yam reproductive biology and diversification.
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Affiliation(s)
- Fabien Cormier
- CIRAD, UMR AGAP Institut, 97170, Petit-Bourg, Guadeloupe, France
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398, Montpellier, France
| | - Guillaume Martin
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398, Montpellier, France
- CIRAD, UMR AGAP Institut, F-34398, Montpellier, France
| | - Hélène Vignes
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398, Montpellier, France
- CIRAD, UMR AGAP Institut, F-34398, Montpellier, France
| | - Laurie Lachman
- CIRAD, UMR AGAP Institut, 97170, Petit-Bourg, Guadeloupe, France
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398, Montpellier, France
- Univ. Des Antilles, Pôle Guadeloupe, IUT Saint Claude, Guadeloupe, France
| | - Denis Cornet
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398, Montpellier, France
- CIRAD, UMR AGAP Institut, F-34398, Montpellier, France
| | - Yoana Faure
- INRA, UR ASTRO Agrosytèmes Tropicaux, Petit-Bourg, Guadeloupe, France
| | - Erick Maledon
- CIRAD, UMR AGAP Institut, 97170, Petit-Bourg, Guadeloupe, France
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398, Montpellier, France
| | - Pierre Mournet
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398, Montpellier, France
- CIRAD, UMR AGAP Institut, F-34398, Montpellier, France
| | - Gemma Arnau
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398, Montpellier, France
- CIRAD, UMR AGAP Institut, F-34398, Montpellier, France
| | - Hâna Chaïr
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, F-34398, Montpellier, France.
- CIRAD, UMR AGAP Institut, F-34398, Montpellier, France.
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37
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Wu M, Haak DC, Anderson GJ, Hahn MW, Moyle LC, Guerrero RF. Inferring the Genetic Basis of Sex Determination from the Genome of a Dioecious Nightshade. Mol Biol Evol 2021; 38:2946-2957. [PMID: 33769517 PMCID: PMC8233512 DOI: 10.1093/molbev/msab089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Dissecting the genetic mechanisms underlying dioecy (i.e., separate female and male individuals) is critical for understanding the evolution of this pervasive reproductive strategy. Nonetheless, the genetic basis of sex determination remains unclear in many cases, especially in systems where dioecy has arisen recently. Within the economically important plant genus Solanum (∼2,000 species), dioecy is thought to have evolved independently at least 4 times across roughly 20 species. Here, we generate the first genome sequence of a dioecious Solanum and use it to ascertain the genetic basis of sex determination in this species. We de novo assembled and annotated the genome of Solanum appendiculatum (assembly size: ∼750 Mb scaffold N50: 0.92 Mb; ∼35,000 genes), identified sex-specific sequences and their locations in the genome, and inferred that males in this species are the heterogametic sex. We also analyzed gene expression patterns in floral tissues of males and females, finding approximately 100 genes that are differentially expressed between the sexes. These analyses, together with observed patterns of gene-family evolution specific to S. appendiculatum, consistently implicate a suite of genes from the regulatory network controlling pectin degradation and modification in the expression of sex. Furthermore, the genome of a species with a relatively young sex-determination system provides the foundational resources for future studies on the independent evolution of dioecy in this clade.
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Affiliation(s)
- Meng Wu
- Department of Biology, Indiana University, Bloomington, IN, USA
| | - David C Haak
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA, USA
| | - Gregory J Anderson
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - Matthew W Hahn
- Department of Biology, Indiana University, Bloomington, IN, USA.,Department of Computer Science, Indiana University, Bloomington, IN, USA
| | - Leonie C Moyle
- Department of Biology, Indiana University, Bloomington, IN, USA
| | - Rafael F Guerrero
- Department of Computer Science, Indiana University, Bloomington, IN, USA.,Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
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Witherspoon L, Dergham A, Flannigan R. Y-microdeletions: a review of the genetic basis for this common cause of male infertility. Transl Androl Urol 2021; 10:1383-1390. [PMID: 33850774 PMCID: PMC8039600 DOI: 10.21037/tau-19-599] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The human Y-chromosome contains genetic material responsible for normal testis development and spermatogenesis. The long arm (Yq) of the Y-chromosome has been found to be susceptible to self-recombination during spermatogenesis predisposing this area to deletions. The incidence of these deletions is estimated to be 1/4,000 in the general population but has been found to be much higher in infertile men. Currently, Y-microdeletions are the second most commonly identified genetic cause of male infertility after Klinefelter syndrome. This has led to testing for these deletions becoming standard practice in men with azoospermia and severe oligospermia. There are three commonly identified Y-microdeletions in infertile males, termed azoospermia factor (AZF) microdeletions AZFa, AZFb and AZFc. With increased understanding and investigation of this genetic basis for infertility a more comprehensive understanding of these deletions has evolved, with several other deletion subtypes being identified. Understanding the genetic basis and pathology behind these Y-microdeletions is essential for any clinician involved in reproductive medicine. In this review we discuss the genetic basis of Y-microdeletions, the various subtypes of deletions, and current technologies available for testing. Our understanding of this issue is evolving in many areas, and in this review we highlight future testing opportunities that may allow us to stratify men with Y-microdeletion associated infertility more accurately
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Affiliation(s)
- Luke Witherspoon
- Division of Urology, Department of Surgery, The Ottawa Hospital and University of Ottawa, Ottawa, ON, Canada
| | - Ali Dergham
- School of Medicine, Faculty of Health Sciences, Queen's University, Kingston, ON, Canada
| | - Ryan Flannigan
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.,Department of Urology, Weill Cornell Medicine, New York, NY, USA
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39
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Li D, Pan S, Zhang H, Fu Y, Peng Z, Zhang L, Peng S, Xu F, Huang H, Shi R, Zheng H, Peng Y, Tan Z. A comprehensive microsatellite landscape of human Y-DNA at kilobase resolution. BMC Genomics 2021; 22:76. [PMID: 33482734 PMCID: PMC7821415 DOI: 10.1186/s12864-021-07389-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/13/2021] [Indexed: 12/12/2022] Open
Abstract
Background Though interest in human simple sequence repeats (SSRs) is increasing, little is known about the exact distributional features of numerous SSRs in human Y-DNA at chromosomal level. Herein, totally 540 maps were established, which could clearly display SSR landscape in every bin of 1 k base pairs (Kbp) along the sequenced part of human reference Y-DNA (NC_000024.10), by our developed differential method for improving the existing method to reveal SSR distributional characteristics in large genomic sequences. Results The maps show that SSRs accumulate significantly with forming density peaks in at least 2040 bins of 1 Kbp, which involve different coding, noncoding and intergenic regions of the Y-DNA, and 10 especially high density peaks were reported to associate with biological significances, suggesting that the other hundreds of especially high density peaks might also be biologically significant and worth further analyzing. In contrast, the maps also show that SSRs are extremely sparse in at least 207 bins of 1 Kbp, including many noncoding and intergenic regions of the Y-DNA, which is inconsistent with the widely accepted view that SSRs are mostly rich in these regions, and these sparse distributions are possibly due to powerfully regional selection. Additionally, many regions harbor SSR clusters with same or similar motif in the Y-DNA. Conclusions These 540 maps may provide the important information of clearly position-related SSR distributional features along the human reference Y-DNA for better understanding the genome structures of the Y-DNA. This study may contribute to further exploring the biological significance and distribution law of the huge numbers of SSRs in human Y-DNA. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07389-5.
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Affiliation(s)
- Douyue Li
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Saichao Pan
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Hongxi Zhang
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Yongzhuo Fu
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Zhuli Peng
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Liang Zhang
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Shan Peng
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Fei Xu
- Department of Mathematics, Wilfrid Laurier University, Waterloo, Ontario, N2L 3C5, Canada
| | - Hanrou Huang
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Ruixue Shi
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Heping Zheng
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Yousong Peng
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China
| | - Zhongyang Tan
- Bioinformatics Center, College of Biology, Hunan University, Changsha, 410082, China.
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40
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Abstract
Model organisms are extensively used in research as accessible and convenient systems for studying a particular area or question in biology. Traditionally, only a limited number of organisms have been studied in detail, but modern genomic tools are enabling researchers to extend beyond the set of classical model organisms to include novel species from less-studied phylogenetic groups. This review focuses on model species for an important group of multicellular organisms, the brown algae. The development of genetic and genomic tools for the filamentous brown alga Ectocarpus has led to it emerging as a general model system for this group, but additional models, such as Fucus or Dictyota dichotoma, remain of interest for specific biological questions. In addition, Saccharina japonica has emerged as a model system to directly address applied questions related to algal aquaculture. We discuss the past, present, and future of brown algal model organisms in relation to the opportunities and challenges in brown algal research.
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Affiliation(s)
- Susana M Coelho
- Laboratory of Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR), CNRS, Sorbonne Université, 29680 Roscoff, France;
- Current affiliation: Department of Algal Development and Evolution, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany;
| | - J Mark Cock
- Laboratory of Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR), CNRS, Sorbonne Université, 29680 Roscoff, France;
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41
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Niayale R, Cui Y, Adzitey F. Male hybrid sterility in the cattle-yak and other bovines: a review. Biol Reprod 2020; 104:495-507. [PMID: 33185248 DOI: 10.1093/biolre/ioaa207] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 09/16/2020] [Accepted: 11/11/2020] [Indexed: 12/19/2022] Open
Abstract
Hybridization is important for both animal breeders attempting to fix new phenotypic traits and researchers trying to unravel the mechanism of reproductive barriers in hybrid species and the process of speciation. In interspecies animal hybrids, gains made in terms of adaptation to environmental conditions and hybrid vigor may be offset by reduced fertility or sterility. Bovine hybrids exhibit remarkable hybrid vigor compared to their parents. However, the F1 male hybrid exhibits sterility, whereas the female is fertile. This male-biased sterility is consistent with the Haldane rule where heterogametic sex is preferentially rare, absent, or sterile in the progeny of two different species. The obstacle of fixing favorable traits and passing them to subsequent generations due to the male sterility is a major setback in improving the reproductive potential of bovines through hybridization. Multiperspective approaches such as molecular genetics, proteomics, transcriptomics, physiology, and endocrinology have been used by several researchers over the past decade in an attempt to unravel the potential mechanisms underlying male hybrid sterility. However, the mechanism of sterility in the hybrid male is still not completely unravelled. This review seeks to provide an update of the mechanisms of the sterility in the cattle-yak and other bovines.
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Affiliation(s)
- Robert Niayale
- Laboratory of Animal Anatomy & Tissue Embryology, Department of Basic Veterinary Medicine, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, Gansu Province, China.,Faculty of Agriculture, Animal Science Department, University for Development Studies, Tamale, Ghana
| | - Yan Cui
- Laboratory of Animal Anatomy & Tissue Embryology, Department of Basic Veterinary Medicine, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, Gansu Province, China
| | - Fredrick Adzitey
- Faculty of Agriculture, Animal Science Department, University for Development Studies, Tamale, Ghana
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42
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Yazdi HP, Silva WTAF, Suh A. Why Do Some Sex Chromosomes Degenerate More Slowly Than Others? The Odd Case of Ratite Sex Chromosomes. Genes (Basel) 2020; 11:E1153. [PMID: 33007827 PMCID: PMC7601716 DOI: 10.3390/genes11101153] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 09/25/2020] [Accepted: 09/28/2020] [Indexed: 01/10/2023] Open
Abstract
The hallmark of sex chromosome evolution is the progressive suppression of recombination which leads to subsequent degeneration of the non-recombining chromosome. In birds, species belonging to the two major clades, Palaeognathae (including tinamous and flightless ratites) and Neognathae (all remaining birds), show distinctive patterns of sex chromosome degeneration. Birds are female heterogametic, in which females have a Z and a W chromosome. In Neognathae, the highly-degenerated W chromosome seems to have followed the expected trajectory of sex chromosome evolution. In contrast, among Palaeognathae, sex chromosomes of ratite birds are largely recombining. The underlying reason for maintenance of recombination between sex chromosomes in ratites is not clear. Degeneration of the W chromosome might have halted or slowed down due to a multitude of reasons ranging from selective processes, such as a less pronounced effect of sexually antagonistic selection, to neutral processes, such as a slower rate of molecular evolution in ratites. The production of genome assemblies and gene expression data for species of Palaeognathae has made it possible, during recent years, to have a closer look at their sex chromosome evolution. Here, we critically evaluate the understanding of the maintenance of recombination in ratites in light of the current data. We conclude by highlighting certain aspects of sex chromosome evolution in ratites that require further research and can potentially increase power for the inference of the unique history of sex chromosome evolution in this lineage of birds.
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Affiliation(s)
| | | | - Alexander Suh
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK;
- Department of Organismal Biology—Systematic Biology, Uppsala University, SE-752 36 Uppsala, Sweden
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43
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Construction of high-density genetic maps defined sex determination region of the Y chromosome in spinach. Mol Genet Genomics 2020; 296:41-53. [DOI: 10.1007/s00438-020-01723-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 09/04/2020] [Indexed: 12/18/2022]
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44
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Gomes I, Pinto N, Antão-Sousa S, Gomes V, Gusmão L, Amorim A. Twenty Years Later: A Comprehensive Review of the X Chromosome Use in Forensic Genetics. Front Genet 2020; 11:926. [PMID: 33093840 PMCID: PMC7527635 DOI: 10.3389/fgene.2020.00926] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 07/24/2020] [Indexed: 12/12/2022] Open
Abstract
The unique structure of the X chromosome shaped by evolution has led to the present gender-specific genetic differences, which are not shared by its counterpart, the Y chromosome, and neither by the autosomes. In males, recombination between the X and Y chromosomes is limited to the pseudoautosomal regions, PAR1 and PAR2; therefore, in males, the X chromosome is (almost) entirely transmitted to female offspring. On the other hand, the X chromosome is present in females with two copies that recombine along the whole chromosome during female meiosis and that is transmitted to both female and male descendants. These transmission characteristics, besides the obvious clinical impact (sex chromosome aneuploidies are extremely frequent), make the X chromosome an irreplaceable genetic tool for population genetic-based studies as well as for kinship and forensic investigations. In the early 2000s, the number of publications using X-chromosomal polymorphisms in forensic and population genetic applications increased steadily. However, nearly 20 years later, we observe a conspicuous decrease in the rate of these publications. In light of this observation, the main aim of this article is to provide a comprehensive review of the advances and applications of X-chromosomal markers in population and forensic genetics over the last two decades. The foremost relevant topics are addressed as: (i) developments concerning the number and types of markers available, with special emphasis on short tandem repeat (STR) polymorphisms (STR nomenclatures and practical concerns); (ii) overview of worldwide population (frequency) data; (iii) the use of X-chromosomal markers in (complex) kinship testing and the forensic statistical evaluation of evidence; (iv) segregation and mutation studies; and (v) current weaknesses and future prospects.
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Affiliation(s)
- Iva Gomes
- Institute for Research and Innovation in Health Sciences (i3S), University of Porto, Porto, Portugal.,Institute of Molecular Pathology and Immunology, University of Porto (IPATIMUP), Porto, Portugal
| | - Nádia Pinto
- Institute for Research and Innovation in Health Sciences (i3S), University of Porto, Porto, Portugal.,Institute of Molecular Pathology and Immunology, University of Porto (IPATIMUP), Porto, Portugal.,Center of Mathematics, Faculty of Sciences, University of Porto, Porto, Portugal
| | - Sofia Antão-Sousa
- Institute for Research and Innovation in Health Sciences (i3S), University of Porto, Porto, Portugal.,Institute of Molecular Pathology and Immunology, University of Porto (IPATIMUP), Porto, Portugal.,Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal.,DNA Diagnostic Laboratory (LDD), State University of Rio de Janeiro (UERJ), Rio de Janeiro, Brazil
| | - Verónica Gomes
- Institute for Research and Innovation in Health Sciences (i3S), University of Porto, Porto, Portugal.,Institute of Molecular Pathology and Immunology, University of Porto (IPATIMUP), Porto, Portugal
| | - Leonor Gusmão
- DNA Diagnostic Laboratory (LDD), State University of Rio de Janeiro (UERJ), Rio de Janeiro, Brazil
| | - António Amorim
- Institute for Research and Innovation in Health Sciences (i3S), University of Porto, Porto, Portugal.,Institute of Molecular Pathology and Immunology, University of Porto (IPATIMUP), Porto, Portugal.,Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal
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45
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Abstract
Females and males may face different selection pressures. Accordingly, alleles that confer a benefit for one sex often incur a cost for the other. Classic evolutionary theory holds that the X chromosome, whose sex-biased transmission sees it spending more time in females, should value females more than males, whereas autosomes, whose transmission is unbiased, should value both sexes equally. However, recent mathematical and empirical studies indicate that male-beneficial alleles may be more favoured by the X chromosome than by autosomes. Here we develop a gene's-eye-view approach that reconciles the classic view with these recent discordant results, by separating a gene's valuation of female versus male fitness from its ability to induce fitness effects in either sex. We use this framework to generate new comparative predictions for sexually antagonistic evolution in relation to dosage compensation, sex-specific mortality and assortative mating, revealing how molecular mechanisms, ecology and demography drive variation in masculinization versus feminization across the genome.
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Affiliation(s)
| | - Andy Gardner
- School of Biology, University of St Andrews, St Andrews KY16 9TH, UK
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46
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Furman BLS, Metzger DCH, Darolti I, Wright AE, Sandkam BA, Almeida P, Shu JJ, Mank JE. Sex Chromosome Evolution: So Many Exceptions to the Rules. Genome Biol Evol 2020; 12:750-763. [PMID: 32315410 PMCID: PMC7268786 DOI: 10.1093/gbe/evaa081] [Citation(s) in RCA: 98] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2020] [Indexed: 01/10/2023] Open
Abstract
Genomic analysis of many nonmodel species has uncovered an incredible diversity of sex chromosome systems, making it possible to empirically test the rich body of evolutionary theory that describes each stage of sex chromosome evolution. Classic theory predicts that sex chromosomes originate from a pair of homologous autosomes and recombination between them is suppressed via inversions to resolve sexual conflict. The resulting degradation of the Y chromosome gene content creates the need for dosage compensation in the heterogametic sex. Sex chromosome theory also implies a linear process, starting from sex chromosome origin and progressing to heteromorphism. Despite many convergent genomic patterns exhibited by independently evolved sex chromosome systems, and many case studies supporting these theoretical predictions, emerging data provide numerous interesting exceptions to these long-standing theories, and suggest that the remarkable diversity of sex chromosomes is matched by a similar diversity in their evolution. For example, it is clear that sex chromosome pairs are not always derived from homologous autosomes. In addition, both the cause and the mechanism of recombination suppression between sex chromosome pairs remain unclear, and it may be that the spread of recombination suppression is a more gradual process than previously thought. It is also clear that dosage compensation can be achieved in many ways, and displays a range of efficacy in different systems. Finally, the remarkable turnover of sex chromosomes in many systems, as well as variation in the rate of sex chromosome divergence, suggest that assumptions about the inevitable linearity of sex chromosome evolution are not always empirically supported, and the drivers of the birth-death cycle of sex chromosome evolution remain to be elucidated. Here, we concentrate on how the diversity in sex chromosomes across taxa highlights an equal diversity in each stage of sex chromosome evolution.
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Affiliation(s)
- Benjamin L S Furman
- Beaty Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - David C H Metzger
- Beaty Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Iulia Darolti
- Beaty Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alison E Wright
- Department of Animal and Plant Sciences, University of Sheffield, United Kingdom
| | - Benjamin A Sandkam
- Beaty Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Pedro Almeida
- Department of Genetics, Evolution and Environment, University College London, United Kingdom
| | - Jacelyn J Shu
- Beaty Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Judith E Mank
- Beaty Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Genetics, Evolution and Environment, University College London, United Kingdom
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47
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The Location of the Pseudoautosomal Boundary in Silene latifolia. Genes (Basel) 2020; 11:genes11060610. [PMID: 32486434 PMCID: PMC7348893 DOI: 10.3390/genes11060610] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/25/2020] [Accepted: 05/28/2020] [Indexed: 12/19/2022] Open
Abstract
Y-chromosomes contain a non-recombining region (NRY), and in many organisms it was shown that the NRY expanded over time. How and why the NRY expands remains unclear. Young sex chromosomes, where NRY expansion occurred recently or is on-going, offer an opportunity to study the causes of this process. Here, we used the plant Silene latifolia, where sex chromosomes evolved ~11 million years ago, to study the location of the boundary between the NRY and the recombining pseudoautosomal region (PAR). The previous work devoted to the NRY/PAR boundary in S. latifolia was based on a handful of genes with locations approximately known from the genetic map. Here, we report the analysis of 86 pseudoautosomal and sex-linked genes adjacent to the S. latifolia NRY/PAR boundary to establish the location of the boundary more precisely. We take advantage of the dense genetic map and polymorphism data from wild populations to identify 20 partially sex-linked genes located in the “fuzzy boundary”, that rarely recombines in male meiosis. Genes proximal to this fuzzy boundary show no evidence of recombination in males, while the genes distal to this partially-sex-linked region are actively recombining in males. Our results provide a more accurate location for the PAR boundary in S. latifolia, which will help to elucidate the causes of PAR boundary shifts leading to NRY expansion over time.
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48
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Li W, Wu H, Li X, Chen Y, Yin T. Fine mapping of the sex locus in Salix triandra confirms a consistent sex determination mechanism in genus Salix. HORTICULTURE RESEARCH 2020; 7:64. [PMID: 32377355 PMCID: PMC7193568 DOI: 10.1038/s41438-020-0289-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 02/27/2020] [Accepted: 03/02/2020] [Indexed: 05/19/2023]
Abstract
Salix triandra belongs to section Amygdalinae in genus Salix, which is in a different section from the willow species in which sex determination has been well studied. Studying sex determination in distantly related willow species will help to clarify whether the sexes of different willows arise through a common sex determination system. For this purpose, we generated an intraspecific full-sib F1 population for S. triandra and constructed high-density genetic linkage maps for the crossing parents using restriction site-associated DNA sequencing and following a two-way pseudo-testcross strategy. With the established maps, the sex locus was positioned in linkage group XV only in the maternal map, and no sex linkage was detected in the paternal map. Consistent with previous findings in other willow species, our study showed that chromosome XV was the incipient sex chromosome and that females were the heterogametic sex in S. triandra. Therefore, sex in this willow species is also determined through a ZW sex determination system. We further performed fine mapping in the vicinity of the sex locus with SSR markers. By comparing the physical and genetic distances for the target interval encompassing the sex determination gene confined by SSRs, severe recombination repression was revealed in the sex determination region in the female map. The recombination rate in the confined interval encompassing the sex locus was approximately eight-fold lower than the genome-wide average. This study provides critical information relevant to sex determination in S. triandra.
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Affiliation(s)
- Wei Li
- The Key Lab of Cultivar Innovation and Germplasm Improvement of Salicaceae, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
| | - Huaitong Wu
- The Key Lab of Cultivar Innovation and Germplasm Improvement of Salicaceae, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
| | - Xiaoping Li
- The Key Lab of Cultivar Innovation and Germplasm Improvement of Salicaceae, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
| | - Yingnan Chen
- The Key Lab of Cultivar Innovation and Germplasm Improvement of Salicaceae, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
| | - Tongming Yin
- The Key Lab of Cultivar Innovation and Germplasm Improvement of Salicaceae, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
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49
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Ma WJ, Carpentier F, Giraud T, Hood ME. Differential Gene Expression between Fungal Mating Types Is Associated with Sequence Degeneration. Genome Biol Evol 2020; 12:243-258. [PMID: 32058544 PMCID: PMC7150583 DOI: 10.1093/gbe/evaa028] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/09/2020] [Indexed: 12/13/2022] Open
Abstract
Degenerative mutations in non-recombining regions, such as in sex chromosomes, may lead to differential expression between alleles if mutations occur stochastically in one or the other allele. Reduced allelic expression due to degeneration has indeed been suggested to occur in various sex-chromosome systems. However, whether an association occurs between specific signatures of degeneration and differential expression between alleles has not been extensively tested, and sexual antagonism can also cause differential expression on sex chromosomes. The anther-smut fungus Microbotryum lychnidis-dioicae is ideal for testing associations between specific degenerative signatures and differential expression because 1) there are multiple evolutionary strata on the mating-type chromosomes, reflecting successive recombination suppression linked to mating-type loci; 2) separate haploid cultures of opposite mating types help identify differential expression between alleles; and 3) there is no sexual antagonism as a confounding factor accounting for differential expression. We found that differentially expressed genes were enriched in the four oldest evolutionary strata compared with other genomic compartments, and that, within compartments, several signatures of sequence degeneration were greater for differentially expressed than non-differentially expressed genes. Two particular degenerative signatures were significantly associated with lower expression levels within differentially expressed allele pairs: upstream insertion of transposable elements and mutations truncating the protein length. Other degenerative mutations associated with differential expression included nonsynonymous substitutions and altered intron or GC content. The association between differential expression and allele degeneration is relevant for a broad range of taxa where mating compatibility or sex is determined by genes located in large regions where recombination is suppressed.
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Affiliation(s)
- Wen-Juan Ma
- Department of Biology, Amherst College, Amherst, MA
| | - Fantin Carpentier
- Ecologie Systematique et Evolution, Université Paris-Saclay, CNRS, AgroParisTech, Orsay, France
| | - Tatiana Giraud
- Ecologie Systematique et Evolution, Université Paris-Saclay, CNRS, AgroParisTech, Orsay, France
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50
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Xu L, Wa Sin SY, Grayson P, Edwards SV, Sackton TB. Evolutionary Dynamics of Sex Chromosomes of Paleognathous Birds. Genome Biol Evol 2020; 11:2376-2390. [PMID: 31329234 PMCID: PMC6735826 DOI: 10.1093/gbe/evz154] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/10/2019] [Indexed: 12/20/2022] Open
Abstract
Standard models of sex chromosome evolution propose that recombination suppression leads to the degeneration of the heterogametic chromosome, as is seen for the Y chromosome in mammals and the W chromosome in most birds. Unlike other birds, paleognaths (ratites and tinamous) possess large nondegenerate regions on their sex chromosomes (PARs or pseudoautosomal regions). It remains unclear why these large PARs are retained over >100 Myr, and how this retention impacts the evolution of sex chromosomes within this system. To address this puzzle, we analyzed Z chromosome evolution and gene expression across 12 paleognaths, several of whose genomes have recently been sequenced. We confirm at the genomic level that most paleognaths retain large PARs. As in other birds, we find that all paleognaths have incomplete dosage compensation on the regions of the Z chromosome homologous to degenerated portions of the W (differentiated regions), but we find no evidence for enrichments of male-biased genes in PARs. We find limited evidence for increased evolutionary rates (faster-Z) either across the chromosome or in differentiated regions for most paleognaths with large PARs, but do recover signals of faster-Z evolution in tinamou species with mostly degenerated W chromosomes, similar to the pattern seen in neognaths. Unexpectedly, in some species, PAR-linked genes evolve faster on average than genes on autosomes, suggested by diverse genomic features to be due to reduced efficacy of selection in paleognath PARs. Our analysis shows that paleognath Z chromosomes are atypical at the genomic level, but the evolutionary forces maintaining largely homomorphic sex chromosomes in these species remain elusive.
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Affiliation(s)
- Luohao Xu
- Department of Molecular Evolution and Development, University of Vienna, Austria
| | - Simon Yung Wa Sin
- Department of Organismic and Evolutionary Biology, Harvard University
- Museum of Comparative Zoology, Harvard University
- School of Biological Sciences, The University of Hong Kong, Hong Kong
| | - Phil Grayson
- Department of Organismic and Evolutionary Biology, Harvard University
- Museum of Comparative Zoology, Harvard University
| | - Scott V Edwards
- Department of Organismic and Evolutionary Biology, Harvard University
- Museum of Comparative Zoology, Harvard University
| | - Timothy B Sackton
- Informatics Group, Division of Science, Harvard University
- Corresponding author: E-mail:
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