51
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Charlesworth D. When and how do sex-linked regions become sex chromosomes? Evolution 2021; 75:569-581. [PMID: 33592115 DOI: 10.1111/evo.14196] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/02/2021] [Accepted: 02/05/2021] [Indexed: 12/22/2022]
Abstract
The attention given to heteromorphism and genetic degeneration of "classical sex chromosomes" (Y chromosomes in XY systems, and the W in ZW systems that were studied first and are best described) has perhaps created the impression that the absence of recombination between sex chromosomes is inevitable. I here argue that continued recombination is often to be expected, that absence of recombination is surprising and demands further study, and that the involvement of selection in reduced recombination is not yet well understood. Despite a long history of investigations of sex chromosome pairs, there is a need for more quantitative approaches to studying sex-linked regions. I describe a scheme to help understand the relationships between different properties of sex-linked regions. Specifically, I focus on their sizes (differentiating between small regions and extensive fully sex-linked ones), the times when they evolved, and their differentiation, and review studies using DNA sequencing in nonmodel organisms that are providing information about the processes causing these properties.
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Affiliation(s)
- Deborah Charlesworth
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, EH9 3JT, United Kingdom
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52
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Wright SI. Deborah Charlesworth, winner of the society for the study of evolution's inaugural lifetime achievement award: Evolutionary biology for the genomics era. Evolution 2021; 75:566-568. [PMID: 33592116 DOI: 10.1111/evo.14195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/01/2021] [Accepted: 02/05/2021] [Indexed: 11/29/2022]
Affiliation(s)
- Stephen I Wright
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, M5S 3B2, Canada
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53
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Hartmann FE, Duhamel M, Carpentier F, Hood ME, Foulongne‐Oriol M, Silar P, Malagnac F, Grognet P, Giraud T. Recombination suppression and evolutionary strata around mating-type loci in fungi: documenting patterns and understanding evolutionary and mechanistic causes. THE NEW PHYTOLOGIST 2021; 229:2470-2491. [PMID: 33113229 PMCID: PMC7898863 DOI: 10.1111/nph.17039] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 09/03/2020] [Indexed: 05/08/2023]
Abstract
Genomic regions determining sexual compatibility often display recombination suppression, as occurs in sex chromosomes, plant self-incompatibility loci and fungal mating-type loci. Regions lacking recombination can extend beyond the genes determining sexes or mating types, by several successive steps of recombination suppression. Here we review the evidence for recombination suppression around mating-type loci in fungi, sometimes encompassing vast regions of the mating-type chromosomes. The suppression of recombination at mating-type loci in fungi has long been recognized and maintains the multiallelic combinations required for correct compatibility determination. We review more recent evidence for expansions of recombination suppression beyond mating-type genes in fungi ('evolutionary strata'), which have been little studied and may be more pervasive than commonly thought. We discuss testable hypotheses for the ultimate (evolutionary) and proximate (mechanistic) causes for such expansions of recombination suppression, including (1) antagonistic selection, (2) association of additional functions to mating-type, such as uniparental mitochondria inheritance, (3) accumulation in the margin of nonrecombining regions of various factors, including deleterious mutations or transposable elements resulting from relaxed selection, or neutral rearrangements resulting from genetic drift. The study of recombination suppression in fungi could thus contribute to our understanding of recombination suppression expansion across a broader range of organisms.
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Affiliation(s)
- Fanny E. Hartmann
- Ecologie Systematique EvolutionBatiment 360Université Paris‐SaclayCNRSAgroParisTechOrsay91400France
| | - Marine Duhamel
- Ecologie Systematique EvolutionBatiment 360Université Paris‐SaclayCNRSAgroParisTechOrsay91400France
- Ruhr‐Universität Bochum, Evolution of Plants and Fungi ‐ Gebäude ND 03/174Universitätsstraße150, 44801 BochumGermany
| | - Fantin Carpentier
- Ecologie Systematique EvolutionBatiment 360Université Paris‐SaclayCNRSAgroParisTechOrsay91400France
| | - Michael E. Hood
- Biology Department, Science CentreAmherst CollegeAmherstMA01002USA
| | | | - Philippe Silar
- Lab Interdisciplinaire Energies DemainUniv Paris DiderotSorbonne Paris CiteParis 13F‐75205France
| | - Fabienne Malagnac
- Institute for Integrative Biology of the Cell (I2BC)Université Paris‐SaclayCEACNRSGif‐sur‐Yvette91198France
| | - Pierre Grognet
- Institute for Integrative Biology of the Cell (I2BC)Université Paris‐SaclayCEACNRSGif‐sur‐Yvette91198France
| | - Tatiana Giraud
- Ecologie Systematique EvolutionBatiment 360Université Paris‐SaclayCNRSAgroParisTechOrsay91400France
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54
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Kostmann A, Kratochvíl L, Rovatsos M. Poorly differentiated XX/XY sex chromosomes are widely shared across skink radiation. Proc Biol Sci 2021; 288:20202139. [PMID: 33468012 PMCID: PMC7893288 DOI: 10.1098/rspb.2020.2139] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 12/23/2020] [Indexed: 11/12/2022] Open
Abstract
Differentiated sex chromosomes are believed to be evolutionarily stable, while poorly differentiated sex chromosomes are considered to be prone to turnovers. With around 1700 currently known species forming ca 15% of reptile species diversity, skinks (family Scincidae) are a very diverse group of squamates known for their large ecological and morphological variability. Skinks generally have poorly differentiated and cytogenetically indistinguishable sex chromosomes, and their sex determination was suggested to be highly variable. Here, we determined X-linked genes in the common sandfish (Scincus scincus) and demonstrate that skinks have shared the same homologous XX/XY sex chromosomes across their wide phylogenetic spectrum for at least 85 million years, approaching the age of the highly differentiated ZZ/ZW sex chromosomes of birds and advanced snakes. Skinks thus demonstrate that even poorly differentiated sex chromosomes can be evolutionarily stable. The conservation of sex chromosomes across skinks allows us to introduce the first molecular sexing method widely applicable in this group.
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Affiliation(s)
| | | | - Michail Rovatsos
- Department of Ecology, Faculty of Science, Charles University, Prague, Czech Republic
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55
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Almeida P, Sandkam BA, Morris J, Darolti I, Breden F, Mank JE. Divergence and Remarkable Diversity of the Y Chromosome in Guppies. Mol Biol Evol 2021; 38:619-633. [PMID: 33022040 PMCID: PMC7826173 DOI: 10.1093/molbev/msaa257] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The guppy sex chromosomes show an extraordinary diversity in divergence across populations and closely related species. In order to understand the dynamics of the guppy Y chromosome, we used linked-read sequencing to assess Y chromosome evolution and diversity across upstream and downstream population pairs that vary in predator and food abundance in three replicate watersheds. Based on our population-specific genome assemblies, we first confirmed and extended earlier reports of two strata on the guppy sex chromosomes. Stratum I shows significant accumulation of male-specific sequence, consistent with Y divergence, and predates the colonization of Trinidad. In contrast, Stratum II shows divergence from the X, but no Y-specific sequence, and this divergence is greater in three replicate upstream populations compared with their downstream pair. Despite longstanding assumptions that sex chromosome recombination suppression is achieved through inversions, we find no evidence of inversions associated with either Stratum I or Stratum II. Instead, we observe a remarkable diversity in Y chromosome haplotypes within each population, even in the ancestral Stratum I. This diversity is likely due to gradual mechanisms of recombination suppression, which, unlike an inversion, allow for the maintenance of multiple haplotypes. In addition, we show that this Y diversity is dominated by low-frequency haplotypes segregating in the population, suggesting a link between haplotype diversity and female preference for rare Y-linked color variation. Our results reveal the complex interplay between recombination suppression and Y chromosome divergence at the earliest stages of sex chromosome divergence.
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Affiliation(s)
- Pedro Almeida
- Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Benjamin A Sandkam
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Jake Morris
- Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Iulia Darolti
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Felix Breden
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Judith E Mank
- Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
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56
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Dufresnes C, Brelsford A, Baier F, Perrin N. When Sex Chromosomes Recombine Only in the Heterogametic Sex: Heterochiasmy and Heterogamety in Hyla Tree Frogs. Mol Biol Evol 2021; 38:192-200. [PMID: 32761205 PMCID: PMC7782862 DOI: 10.1093/molbev/msaa201] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Sex chromosomes are classically predicted to stop recombining in the heterogametic sex, thereby enforcing linkage between sex-determining (SD) and sex-antagonistic (SA) genes. With the same rationale, a pre-existing sex asymmetry in recombination is expected to affect the evolution of heterogamety, for example, a low rate of male recombination might favor transitions to XY systems, by generating immediate linkage between SD and SA genes. Furthermore, the accumulation of deleterious mutations on nonrecombining Y chromosomes should favor XY-to-XY transitions (which discard the decayed Y), but disfavor XY-to-ZW transitions (which fix the decayed Y as an autosome). Like many anuran amphibians, Hyla tree frogs have been shown to display drastic heterochiasmy (males only recombine at chromosome tips) and are typically XY, which seems to fit the above expectations. Instead, here we demonstrate that two species, H. sarda and H. savignyi, share a common ZW system since at least 11 Ma. Surprisingly, the typical pattern of restricted male recombination has been maintained since then, despite female heterogamety. Hence, sex chromosomes recombine freely in ZW females, not in ZZ males. This suggests that heterochiasmy does not constrain heterogamety (and vice versa), and that the role of SA genes in the evolution of sex chromosomes might have been overemphasized.
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Affiliation(s)
- Christophe Dufresnes
- LASER, College of Biology and the Environment, Nanjing Forestry University, Nanjing, People's Republic of China
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Alan Brelsford
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, Riverside, CA
| | - Felix Baier
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, Cambridge, MA
| | - Nicolas Perrin
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
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57
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McKinney GJ, Seeb JE, Pascal CE, Schindler DE, Gilk‐Baumer SE, Seeb LW. Y-chromosome haplotypes are associated with variation in size and age at maturity in male Chinook salmon. Evol Appl 2020; 13:2791-2806. [PMID: 33294023 PMCID: PMC7691470 DOI: 10.1111/eva.13084] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/12/2020] [Accepted: 07/22/2020] [Indexed: 12/17/2022] Open
Abstract
Variation in size and age at maturity is an important component of life history that is influenced by both environmental and genetic factors. In salmonids, large size confers a direct reproductive advantage through increased fecundity and egg quality in females, while larger males gain a reproductive advantage by monopolizing access to females. In addition, variation in size and age at maturity in males can be associated with different reproductive strategies; younger smaller males may gain reproductive success by sneaking among mating pairs. In both sexes, there is a trade-off between older age and increased reproductive success and increased risk of mortality by delaying reproduction. We identified four Y-chromosome haplogroups that showed regional- and population-specific variation in frequency using RADseq data for 21 populations of Alaska Chinook salmon. We then characterized the range-wide distribution of these haplogroups using GT-seq assays. These haplogroups exhibited associations with size at maturity in multiple populations, suggesting that lack of recombination between X and Y-chromosomes has allowed Y-chromosome haplogroups to capture different alleles that influence size at maturity. Ultimately, conservation of life history diversity in Chinook salmon may require conservation of Y-chromosome haplotype diversity.
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Affiliation(s)
| | - James E. Seeb
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWAUSA
| | - Carita E. Pascal
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWAUSA
| | | | | | - Lisa W. Seeb
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWAUSA
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58
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Shearn R, Wright AE, Mousset S, Régis C, Penel S, Lemaitre JF, Douay G, Crouau-Roy B, Lecompte E, Marais GA. Evolutionary stasis of the pseudoautosomal boundary in strepsirrhine primates. eLife 2020; 9:63650. [PMID: 33205751 PMCID: PMC7717902 DOI: 10.7554/elife.63650] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 11/16/2020] [Indexed: 12/11/2022] Open
Abstract
Sex chromosomes are typically comprised of a non-recombining region and a recombining pseudoautosomal region. Accurately quantifying the relative size of these regions is critical for sex-chromosome biology both from a functional and evolutionary perspective. The evolution of the pseudoautosomal boundary (PAB) is well documented in haplorrhines (apes and monkeys) but not in strepsirrhines (lemurs and lorises). Here, we studied the PAB of seven species representing the main strepsirrhine lineages by sequencing a male and a female genome in each species and using sex differences in coverage to identify the PAB. We found that during primate evolution, the PAB has remained unchanged in strepsirrhines whereas several recombination suppression events moved the PAB and shortened the pseudoautosomal region in haplorrhines. Strepsirrhines are well known to have much lower sexual dimorphism than haplorrhines. We suggest that mutations with antagonistic effects between males and females have driven recombination suppression and PAB evolution in haplorrhines.
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Affiliation(s)
- Rylan Shearn
- Laboratoire Biométrie et Biologie Evolutive, CNRS / Univ. Lyon 1, Villeurbanne, France
| | - Alison E Wright
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom
| | - Sylvain Mousset
- Laboratoire Biométrie et Biologie Evolutive, CNRS / Univ. Lyon 1, Villeurbanne, France.,Faculty of Mathematics, University of Vienna, Vienna, Austria
| | - Corinne Régis
- Laboratoire Biométrie et Biologie Evolutive, CNRS / Univ. Lyon 1, Villeurbanne, France
| | - Simon Penel
- Laboratoire Biométrie et Biologie Evolutive, CNRS / Univ. Lyon 1, Villeurbanne, France
| | | | | | - Brigitte Crouau-Roy
- Laboratoire Evolution et Diversité Biologique, CNRS / Univ. Toulouse, Toulouse, France
| | - Emilie Lecompte
- Laboratoire Evolution et Diversité Biologique, CNRS / Univ. Toulouse, Toulouse, France
| | - Gabriel Ab Marais
- Laboratoire Biométrie et Biologie Evolutive, CNRS / Univ. Lyon 1, Villeurbanne, France.,LEAF-Linking Landscape, Environment, Agriculture and Food Dept, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal
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59
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Tao W, Xu L, Zhao L, Zhu Z, Wu X, Min Q, Wang D, Zhou Q. High-quality chromosome-level genomes of two tilapia species reveal their evolution of repeat sequences and sex chromosomes. Mol Ecol Resour 2020; 21:543-560. [PMID: 33035394 DOI: 10.1111/1755-0998.13273] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/14/2020] [Accepted: 09/23/2020] [Indexed: 01/05/2023]
Abstract
Tilapias are one of the most farmed fishes that are coined as "aquatic chicken" by the food industry. Nile tilapia and blue tilapia exhibit very recent transition of sex chromosome systems since their divergence approximately five million years ago, making them a great model for elucidating the molecular and evolutionary mechanisms of sex chromosome turnovers. Studies of their sex-determining pathways are also critical for developing genetic sex control in aquaculture. We report here the newly produced genomes of Nile tilapia and blue tilapia that integrate long-read sequencing and chromatin conformation data. The two nearly complete genomes have anchored over 97% of the sequences into linkage groups (LGs), and assembled majorities of complex repetitive regions including telomeres, centromeres and rDNA clusters. In particular, we inferred two episodes of repeat expansion at LG3 respectively in the ancestor of cichlids and that of tilapias. The consequential large heterochromatic region concentrated at one end of LG3 comprises tandem arrays of mRNA and small RNA genes, among which we have identified a candidate female determining gene Paics in blue tilapia. Paics shows female-specific patterns of single-nucleotide variants, copy numbers and expression patterns in gonads during early gonadogenesis. Our work provides a very important genomic resource for functional studies of cichlids, and suggested that unequal distribution of repeat content that impacts the local recombination rate might make some chromosomes more likely to become sex chromosomes.
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Affiliation(s)
- Wenjing Tao
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, China
| | - Luohao Xu
- MOE Laboratory of Biosystems Homeostasis & Protection, Life Sciences Institute, Zhejiang University, Hangzhou, China.,Department of Neuroscience and Developmental Biology, University of Vienna, Vienna, Austria
| | - Lin Zhao
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, China
| | - Zexian Zhu
- MOE Laboratory of Biosystems Homeostasis & Protection, Life Sciences Institute, Zhejiang University, Hangzhou, China
| | - Xin Wu
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, China
| | - Qianwen Min
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, China
| | - Deshou Wang
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, China
| | - Qi Zhou
- MOE Laboratory of Biosystems Homeostasis & Protection, Life Sciences Institute, Zhejiang University, Hangzhou, China.,Department of Neuroscience and Developmental Biology, University of Vienna, Vienna, Austria.,Center for Reproductive Medicine, The 2nd Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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60
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Gammerdinger WJ, Toups MA, Vicoso B. Disagreement in F ST estimators: A case study from sex chromosomes. Mol Ecol Resour 2020; 20:1517-1525. [PMID: 32543001 PMCID: PMC7689734 DOI: 10.1111/1755-0998.13210] [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] [Received: 07/01/2019] [Accepted: 05/27/2020] [Indexed: 12/25/2022]
Abstract
Sewall Wright developed FST for describing population differentiation and it has since been extended to many novel applications, including the detection of homomorphic sex chromosomes. However, there has been confusion regarding the expected estimate of FST for a fixed difference between the X- and Y-chromosome when comparing males and females. Here, we attempt to resolve this confusion by contrasting two common FST estimators and explain why they yield different estimates when applied to the case of sex chromosomes. We show that this difference is true for many allele frequencies, but the situation characterized by fixed differences between the X- and Y-chromosome is among the most extreme. To avoid additional confusion, we recommend that all authors using FST clearly state which estimator of FST their work uses.
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Affiliation(s)
| | - Melissa A. Toups
- Institute of Science and Technology AustriaKlosterneuburgAustria
| | - Beatriz Vicoso
- Institute of Science and Technology AustriaKlosterneuburgAustria
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61
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Morris J, Darolti I, van der Bijl W, Mank JE. High-resolution characterization of male ornamentation and re-evaluation of sex linkage in guppies. Proc Biol Sci 2020; 287:20201677. [PMID: 33081622 PMCID: PMC7661287 DOI: 10.1098/rspb.2020.1677] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 09/22/2020] [Indexed: 12/25/2022] Open
Abstract
Coloration plays a key role in the ecology of many species, influencing how an organism interacts with its environment, other species and conspecifics. Guppies are sexually dimorphic, with males displaying sexually selected coloration resulting from female preference. Previous work has suggested that much of guppy colour pattern variation is Y-linked. However, it remains unclear how many individual colour patterns are Y-linked in natural populations as much of the previous work has focused on phenotypes either not found in the wild, or aggregate measures such as total colour area. Moreover, ornaments have traditionally been identified and delineated by hand, and computational methods now make it possible to extract pixels and identify ornaments with automated methods, reducing the potential for human bias. Here we developed a pipeline for semi-automated ornament identification and high-resolution image analysis of male guppy colour patterns and applied it to a multigenerational pedigree. Our results show that loci controlling the presence or the absence of individual male ornaments in our population are not predominantly Y-linked. However, we find that ornaments of similar colour are not independent of each other, and modifier loci that affect whole animal coloration appear to be at least partially Y-linked. Considering these results, Y-linkage of individual ornaments may not be important in driving colour changes in natural populations of guppies, or in expansions of the non-recombining Y region, while Y-linked modifier loci that affect aggregate traits may well play an important role.
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Affiliation(s)
- Jake Morris
- Department of Genetics, Evolution and Environment, University College London, London, UK
| | - Iulia Darolti
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Wouter van der Bijl
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Judith E. Mank
- Department of Genetics, Evolution and Environment, University College London, London, UK
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
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62
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Charlesworth D, Bergero R, Graham C, Gardner J, Yong L. Locating the Sex Determining Region of Linkage Group 12 of Guppy ( Poecilia reticulata). G3 (BETHESDA, MD.) 2020; 10:3639-3649. [PMID: 32753367 PMCID: PMC7534449 DOI: 10.1534/g3.120.401573] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 07/29/2020] [Indexed: 01/04/2023]
Abstract
Despite over 100 years of study, the location of the fully sex-linked region of the guppy (Poecilia reticulata) carrying the male-determining locus, and the regions where the XY pair recombine, remain unclear. Previous population genomics studies to determine these regions used small samples from recently bottlenecked captive populations, which increase the false positive rate of associations between individuals' sexes and SNPs. Using new data from multiple natural populations, we show that a recently proposed candidate for this species' male-determining gene is probably not completely sex-linked, leaving the maleness factor still unidentified. Variants in the chromosome 12 region carrying the candidate gene sometimes show linkage disequilibrium with the sex-determining factor, but no consistently male-specific variant has yet been found. Our genetic mapping with molecular markers spread across chromosome 12 confirms that this is the guppy XY pair. We describe two families with recombinants between the X and Y chromosomes, which confirm that the male-determining locus is in the region identified by all previous studies, near the terminal pseudo-autosomal region (PAR), which crosses over at a very high rate in males. We correct the PAR marker order, and assign two unplaced scaffolds to the PAR. We also detect a duplication, with one copy in the male-determining region, explaining signals of sex linkage in a more proximal region.
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Affiliation(s)
- Deborah Charlesworth
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, West Mains Road, EH9 3LF, UK
| | - Roberta Bergero
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, West Mains Road, EH9 3LF, UK
| | - Chay Graham
- University of Cambridge, Department of Biochemistry, Sanger Building, 80 Tennis Ct Rd, Cambridge CB2 1GA, UK
| | - Jim Gardner
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, West Mains Road, EH9 3LF, UK
| | - Lengxob Yong
- Centre for Ecology and Conservation, University of Exeter, Penryn, Falmouth, Cornwall, TR10 9FE, UK
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63
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Darolti I, Wright AE, Mank JE. Guppy Y Chromosome Integrity Maintained by Incomplete Recombination Suppression. Genome Biol Evol 2020; 12:965-977. [PMID: 32426836 PMCID: PMC7337182 DOI: 10.1093/gbe/evaa099] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/13/2020] [Indexed: 12/11/2022] Open
Abstract
The loss of recombination triggers divergence between the sex chromosomes and promotes degeneration of the sex-limited chromosome. Several livebearers within the genus Poecilia share a male-heterogametic sex chromosome system that is roughly 20 Myr old, with extreme variation in the degree of Y chromosome divergence. In Poecilia picta, the Y is highly degenerate and associated with complete X chromosome dosage compensation. In contrast, although recombination is restricted across almost the entire length of the sex chromosomes in Poecilia reticulata and Poecilia wingei, divergence between the X chromosome and the Y chromosome is very low. This clade therefore offers a unique opportunity to study the forces that accelerate or hinder sex chromosome divergence. We used RNA-seq data from multiple families of both P. reticulata and P. wingei, the species with low levels of sex chromosome divergence, to differentiate X and Y coding sequences based on sex-limited SNP inheritance. Phylogenetic tree analyses reveal that occasional recombination has persisted between the sex chromosomes for much of their length, as X- and Y-linked sequences cluster by species instead of by gametolog. This incomplete recombination suppression maintains the extensive homomorphy observed in these systems. In addition, we see differences between the previously identified strata in the phylogenetic clustering of X-Y orthologs, with those that cluster by chromosome located in the older stratum, the region previously associated with the sex-determining locus. However, recombination arrest appears to have expanded throughout the sex chromosomes more gradually instead of through a stepwise process associated with inversions.
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Affiliation(s)
- Iulia Darolti
- Biodiversity Research Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alison E Wright
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, United Kingdom
| | - Judith E Mank
- Biodiversity Research Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
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64
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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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65
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Abstract
Sex differences in overall recombination rates are well known, but little theoretical or empirical attention has been given to how and why sexes differ in their recombination landscapes: the patterns of recombination along chromosomes. In the first scientific review of this phenomenon, we find that recombination is biased toward telomeres in males and more uniformly distributed in females in most vertebrates and many other eukaryotes. Notable exceptions to this pattern exist, however. Fine-scale recombination patterns also frequently differ between males and females. The molecular mechanisms responsible for sex differences remain unclear, but chromatin landscapes play a role. Why these sex differences evolve also is unclear. Hypotheses suggest that they may result from sexually antagonistic selection acting on coding genes and their regulatory elements, meiotic drive in females, selection during the haploid phase of the life cycle, selection against aneuploidy, or mechanistic constraints. No single hypothesis, however, can adequately explain the evolution of sex differences in all cases. Sex-specific recombination landscapes have important consequences for population differentiation and sex chromosome evolution.
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Affiliation(s)
- Jason M. Sardell
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712
| | - Mark Kirkpatrick
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712
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66
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Phillips BC, Rodrigues N, Jansen van Rensburg A, Perrin N. Phylogeography, more than elevation, accounts for sex chromosome differentiation in Swiss populations of the common frog (Rana temporaria). Evolution 2019; 74:644-654. [PMID: 31596503 DOI: 10.1111/evo.13860] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/01/2019] [Indexed: 01/18/2023]
Abstract
Sex chromosomes in vertebrates range from highly heteromorphic (as in most birds and mammals) to strictly homomorphic (as in many fishes, amphibians, and nonavian reptiles). Reasons for these contrasted evolutionary trajectories remain unclear, but species such as common frogs with polymorphism in the extent of sex chromosome differentiation may potentially deliver important clues. By investigating 92 common frog populations from a wide range of elevations throughout Switzerland, we show that sex chromosome differentiation strongly correlates with alleles at the candidate sex-determining gene Dmrt1. Y-specific Dmrt1 haplotypes cluster into two main haplogroups, YA and YB , with a phylogeographic signal that parallels mtDNA haplotypes: YA populations, with mostly well-differentiated sex chromosomes, occur primarily south of the main alpine ridge that bisects Switzerland, whereas YB populations, with mostly undifferentiated (proto-)sex chromosomes, occur north of this ridge. Elevation has only a marginal effect, opposing previous suggestions of a major role for climate on sex chromosome differentiation. The Y-haplotype effect might result from differences in the penetrance of alleles at the sex-determining locus (such that sex reversal and ensuing X-Y recombination are more frequent in YB populations), and/or fixation of an inversion on YA (as supported by the empirical observation that YA haplotypes might not recombine in XYA females).
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Affiliation(s)
- Barret C Phillips
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Nicolas Rodrigues
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | | | - Nicolas Perrin
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
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67
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Molecular and evolutionary dynamics of animal sex-chromosome turnover. Nat Ecol Evol 2019; 3:1632-1641. [DOI: 10.1038/s41559-019-1050-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 10/24/2019] [Indexed: 11/08/2022]
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68
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Dor L, Shirak A, Kohn YY, Gur T, Weller JI, Zilberg D, Seroussi E, Ron M. Mapping of the Sex Determining Region on Linkage Group 12 of Guppy ( Poecilia reticulata). G3 (BETHESDA, MD.) 2019; 9:3867-3875. [PMID: 31551287 PMCID: PMC6829149 DOI: 10.1534/g3.119.400656] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 09/19/2019] [Indexed: 11/18/2022]
Abstract
Poecilia reticulata is one of the most popular ornamental fish species with a higher demand for males due to their large colorful fins. The objectives of this study were mapping of the sex-determining (SD) region on linkage group 12 of guppy, and identification of a sex specific marker. We generated eight polymorphic microsatellite markers distributed along the distal 5.4 Mbp sequence of the previously identified SD region on linkage group (LG) 12. The markers were tested for association with sex in 156 individuals of the Red Blonde and Flame strains, and 126 progeny of four full-sibs Red Blonde families. A male-specific allele was found for microsatellite gu1066 at position of 25.3 Mbp on LG12 for both strains, and gu832 at position 24.4 Mbp for the Flame strain. Thus, a region of 0.9 Mbp between these markers, harboring 27 annotated genes, was selected for analysis. Based on association of copy number variation and sex determination we mapped a duplicated region between LGs 9 and 12, of 1.26 Mbp, containing 59 genes on LG12. The common interval between the segment bounded by gu1066 and gu832, and the duplicated region of 0.43 Mbp on LG12 harbors 11 genes of which 6 have multiple copies (54%). Growth arrest and DNA damage inducible gamma-like (GADD45G-like) is a plausible positional and functional candidate gene for its role in male fertility. We characterized the genomic structure of the gene in guppy, and found two isoforms; but no sex-biased differences were evident in genomic sequence and gene expression.
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Affiliation(s)
- Lior Dor
- Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot 76100, Israel
- Agricultural Research Organization (ARO), Volcani Center, Institute of Animal Science, HaMaccabim Road, P.O.B 15159, 7528809, Rishon LeTsiyon, Israel
| | - Andrey Shirak
- Agricultural Research Organization (ARO), Volcani Center, Institute of Animal Science, HaMaccabim Road, P.O.B 15159, 7528809, Rishon LeTsiyon, Israel
| | - Yair Yaacov Kohn
- Central and Northern Arava Research and Development D.N. Arava Sapir, 86825 Israel, and
| | - Tal Gur
- Central and Northern Arava Research and Development D.N. Arava Sapir, 86825 Israel, and
| | - Joel Ira Weller
- Agricultural Research Organization (ARO), Volcani Center, Institute of Animal Science, HaMaccabim Road, P.O.B 15159, 7528809, Rishon LeTsiyon, Israel
| | - Dina Zilberg
- The French Associates Institute for Agriculture and Biotechnology of Drylands, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
| | - Eyal Seroussi
- Agricultural Research Organization (ARO), Volcani Center, Institute of Animal Science, HaMaccabim Road, P.O.B 15159, 7528809, Rishon LeTsiyon, Israel
| | - Micha Ron
- Agricultural Research Organization (ARO), Volcani Center, Institute of Animal Science, HaMaccabim Road, P.O.B 15159, 7528809, Rishon LeTsiyon, Israel,
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69
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Palmer DH, Rogers TF, Dean R, Wright AE. How to identify sex chromosomes and their turnover. Mol Ecol 2019; 28:4709-4724. [PMID: 31538682 PMCID: PMC6900093 DOI: 10.1111/mec.15245] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/05/2019] [Accepted: 09/13/2019] [Indexed: 12/12/2022]
Abstract
Although sex is a fundamental component of eukaryotic reproduction, the genetic systems that control sex determination are highly variable. In many organisms the presence of sex chromosomes is associated with female or male development. Although certain groups possess stable and conserved sex chromosomes, others exhibit rapid sex chromosome evolution, including transitions between male and female heterogamety, and turnover in the chromosome pair recruited to determine sex. These turnover events have important consequences for multiple facets of evolution, as sex chromosomes are predicted to play a central role in adaptation, sexual dimorphism, and speciation. However, our understanding of the processes driving the formation and turnover of sex chromosome systems is limited, in part because we lack a complete understanding of interspecific variation in the mechanisms by which sex is determined. New bioinformatic methods are making it possible to identify and characterize sex chromosomes in a diverse array of non-model species, rapidly filling in the numerous gaps in our knowledge of sex chromosome systems across the tree of life. In turn, this growing data set is facilitating and fueling efforts to address many of the unanswered questions in sex chromosome evolution. Here, we synthesize the available bioinformatic approaches to produce a guide for characterizing sex chromosome system and identity simultaneously across clades of organisms. Furthermore, we survey our current understanding of the processes driving sex chromosome turnover, and highlight important avenues for future research.
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Affiliation(s)
- Daniela H. Palmer
- Department of Animal and Plant SciencesUniversity of SheffieldSheffieldUK
| | - Thea F. Rogers
- Department of Animal and Plant SciencesUniversity of SheffieldSheffieldUK
| | - Rebecca Dean
- Department of Genetics, Evolution and EnvironmentUniversity College LondonLondonUK
| | - Alison E. Wright
- Department of Animal and Plant SciencesUniversity of SheffieldSheffieldUK
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70
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Charlesworth D. Young sex chromosomes in plants and animals. THE NEW PHYTOLOGIST 2019; 224:1095-1107. [PMID: 31222890 DOI: 10.1111/nph.16002] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 06/10/2019] [Indexed: 05/28/2023]
Abstract
A major reason for studying plant sex chromosomes is that they may often be 'young' systems. There is considerable evidence for the independent evolution of separate sexes within plant families or genera, in some cases showing that the maximum possible time during which their sex-determining genes have existed must be much shorter than those of several animal taxa. Consequently, their sex-linked regions could either have evolved soon after genetic sex determination arose or considerably later. Plants, therefore, include species with both young and old systems. I review several questions about the evolution of sex-determining systems and sex chromosomes that require studies of young systems, including: the kinds of mutations involved in the transition to unisexual reproduction from hermaphroditism or monoecy (a form of functional hermaphroditism); the times when they arose; and the extent to which the properties of sex-linked regions of genomes reflect responses to new selective situations created by the presence of a sex-determining locus. I also evaluate which questions are best studied in plants, vs other suitable candidate organisms. Studies of young plant systems can help understand general evolutionary processes that are shared with the sex chromosomes of other organisms.
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Affiliation(s)
- Deborah Charlesworth
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, West Mains Road, Edinburgh, EH9 3LF, UK
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71
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Li X, Veltsos P, Cossard GG, Gerchen J, Pannell JR. YY males of the dioecious plant Mercurialis annua are fully viable but produce largely infertile pollen. THE NEW PHYTOLOGIST 2019; 224:1394-1404. [PMID: 31230365 PMCID: PMC6852596 DOI: 10.1111/nph.16016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 06/10/2019] [Indexed: 05/07/2023]
Abstract
The suppression of recombination during sex-chromosome evolution is thought to be favoured by linkage between the sex-determining locus and sexually antagonistic loci, and leads to the degeneration of the chromosome restricted to the heterogametic sex. Despite substantial evidence for genetic degeneration at the sequence level, the phenotypic effects of the earliest stages of sex-chromosome evolution are poorly known. Here, we compare the morphology, viability and fertility between XY and YY individuals produced by crossing seed-producing males in the dioecious plant Mercurialis annua, which has young sex chromosomes with limited X-Y sequence divergence. We found no significant difference in viability or vegetative morphology between XY and YY males. However, electron microscopy revealed clear differences in pollen anatomy, and YY males were significantly poorer sires in competition with their XY counterparts. Our study suggests either that the X chromosome is required for full male fertility in M. annua, or that male fertility is sensitive to the dosage of relevant Y-linked genes. We discuss the possibility that the maintenance of male-fertility genes on the X chromosome might have been favoured in recent population expansions that selected for the ability of females to produce pollen in the absence of males.
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Affiliation(s)
- Xinji Li
- Department of Ecology and EvolutionUniversity of Lausanne1015LausanneSwitzerland
| | - Paris Veltsos
- Department of BiologyIndiana University1001 East Third StreetBloomingtonIN47405USA
| | - Guillaume G. Cossard
- Integrative Biology of Marine Organisms DepartmentStation Biologique CNRSPlace Georges TeissierRoscoff29688France
| | - Jörn Gerchen
- Department of Ecology and EvolutionUniversity of Lausanne1015LausanneSwitzerland
| | - John R. Pannell
- Department of Ecology and EvolutionUniversity of Lausanne1015LausanneSwitzerland
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72
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Veltsos P, Ridout KE, Toups MA, González-Martínez SC, Muyle A, Emery O, Rastas P, Hudzieczek V, Hobza R, Vyskot B, Marais GAB, Filatov DA, Pannell JR. Early Sex-Chromosome Evolution in the Diploid Dioecious Plant Mercurialis annua. Genetics 2019; 212:815-835. [PMID: 31113811 PMCID: PMC6614902 DOI: 10.1534/genetics.119.302045] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/13/2019] [Indexed: 12/30/2022] Open
Abstract
Suppressed recombination allows divergence between homologous sex chromosomes and the functionality of their genes. Here, we reveal patterns of the earliest stages of sex-chromosome evolution in the diploid dioecious herb Mercurialis annua on the basis of cytological analysis, de novo genome assembly and annotation, genetic mapping, exome resequencing of natural populations, and transcriptome analysis. The genome assembly contained 34,105 expressed genes, of which 10,076 were assigned to linkage groups. Genetic mapping and exome resequencing of individuals across the species range both identified the largest linkage group, LG1, as the sex chromosome. Although the sex chromosomes of M. annua are karyotypically homomorphic, we estimate that about one-third of the Y chromosome, containing 568 transcripts and spanning 22.3 cM in the corresponding female map, has ceased recombining. Nevertheless, we found limited evidence for Y-chromosome degeneration in terms of gene loss and pseudogenization, and most X- and Y-linked genes appear to have diverged in the period subsequent to speciation between M. annua and its sister species M. huetii, which shares the same sex-determining region. Taken together, our results suggest that the M. annua Y chromosome has at least two evolutionary strata: a small old stratum shared with M. huetii, and a more recent larger stratum that is probably unique to M. annua and that stopped recombining ∼1 MYA. Patterns of gene expression within the nonrecombining region are consistent with the idea that sexually antagonistic selection may have played a role in favoring suppressed recombination.
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Affiliation(s)
- Paris Veltsos
- Department of Biology, Indiana University, Bloomington, IN 47405
- Department of Ecology and Evolution, University of Lausanne, CH-1015, Switzerland
| | - Kate E Ridout
- Department of Ecology and Evolution, University of Lausanne, CH-1015, Switzerland
- Department of Plant Sciences, University of Oxford, OX1 3RB, United Kingdom
- Department of Oncology, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom
| | - Melissa A Toups
- Department of Ecology and Evolution, University of Lausanne, CH-1015, Switzerland
- Department of Integrative Biology, University of Texas, Austin, 78712 Texas
| | | | - Aline Muyle
- Laboratoire Biométrie et Biologie Évolutive (UMR 5558), CNRS/Université Lyon 1, 69100 Villeurbanne, France
| | - Olivier Emery
- Department of Ecology and Evolution, University of Lausanne, CH-1015, Switzerland
| | - Pasi Rastas
- University of Helsinki, Institute of Biotechnology, 00014, Finland
| | - Vojtech Hudzieczek
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61200 Brno, Czech Republic
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61200 Brno, Czech Republic
| | - Boris Vyskot
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61200 Brno, Czech Republic
| | | | - Dmitry A Filatov
- Department of Plant Sciences, University of Oxford, OX1 3RB, United Kingdom
| | - John R Pannell
- Department of Ecology and Evolution, University of Lausanne, CH-1015, Switzerland
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73
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Wright AE, Darolti I, Bloch NI, Oostra V, Sandkam BA, Buechel SD, Kolm N, Breden F, Vicoso B, Mank JE. On the power to detect rare recombination events. Proc Natl Acad Sci U S A 2019; 116:12607-12608. [PMID: 31213531 PMCID: PMC6601268 DOI: 10.1073/pnas.1905555116] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Alison E Wright
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, United Kingdom;
| | - Iulia Darolti
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| | - Natasha I Bloch
- Department of Biomedical Engineering, University of Los Andes, Bogotá 111711, Colombia
| | - Vicencio Oostra
- Research Centre for Ecological Change, University of Helsinki, Helsinki FI-00014, Finland
| | - Benjamin A Sandkam
- Department of Zoology, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - Séverine D Buechel
- Department of Zoology, Stockholm University, Stockholm SE-106 91, Sweden
| | - Niclas Kolm
- Department of Zoology, Stockholm University, Stockholm SE-106 91, Sweden
| | - Felix Breden
- Department of Biological Sciences, Simon Fraser University, Burnaby V5A 1S6, Canada
| | - Beatriz Vicoso
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| | - Judith E Mank
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
- Department of Zoology, University of British Columbia, Vancouver V6T 1Z4, Canada
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74
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Reply to Wright et al.: How to explain the absence of extensive Y-specific regions in the guppy sex chromosomes. Proc Natl Acad Sci U S A 2019; 116:12609-12610. [PMID: 31213530 DOI: 10.1073/pnas.1906633116] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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