1
|
Olito C, Ponnikas S, Hansson B, Abbott JK. Consequences of partially recessive deleterious genetic variation for the evolution of inversions suppressing recombination between sex chromosomes1. Evolution 2024; 78:1499-1510. [PMID: 38853722 DOI: 10.1093/evolut/qpae060] [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: 09/07/2023] [Revised: 03/26/2024] [Accepted: 04/25/2024] [Indexed: 06/11/2024]
Abstract
The evolution of suppressed recombination between sex chromosomes is widely hypothesized to be driven by sexually antagonistic selection (SA), where tighter linkage between the sex-determining gene(s) and nearby SA loci is favored when it couples male-beneficial alleles to the proto-Y chromosome, and female-beneficial alleles to the proto-X. Although difficult to test empirically, the SA selection hypothesis overshadows several alternatives, including an incomplete but often-repeated "sheltering" hypothesis which suggests that expansion of the sex-linked region (SLR) reduces the homozygous expression of deleterious mutations at selected loci. Here, we use population genetic models to evaluate the consequences of partially recessive deleterious mutational variation for the evolution of otherwise neutral chromosomal inversions expanding the SLR on proto-Y chromosomes. Both autosomal and SLR-expanding inversions face a race against time: lightly-loaded inversions are initially beneficial, but eventually become deleterious as they accumulate new mutations, after which their chances of fixing become negligible. In contrast, initially unloaded inversions eventually become neutral as their deleterious load reaches the same equilibrium as non-inverted haplotypes. Despite the differences in inheritance and indirect selection, SLR-expanding inversions exhibit similar evolutionary dynamics to autosomal inversions over many biologically plausible parameter conditions. Differences emerge when the population average mutation load is quite high; in this case large autosomal inversions that are lucky enough to be mutation-free can rise to intermediate to high frequencies where selection in homozygotes becomes important (Y-linked inversions never appear as homozygous karyotypes); conditions requiring either high mutation rates, highly recessive deleterious mutations, weak selection, or a combination thereof.
Collapse
Affiliation(s)
- Colin Olito
- Department of Biology, Lund University, Lund, Sweden
| | - Suvi Ponnikas
- Department of Biology, Lund University, Lund, Sweden
| | - Bengt Hansson
- Department of Biology, Lund University, Lund, Sweden
| | | |
Collapse
|
2
|
Zhu Z, Younas L, Zhou Q. Evolution and regulation of animal sex chromosomes. Nat Rev Genet 2024:10.1038/s41576-024-00757-3. [PMID: 39026082 DOI: 10.1038/s41576-024-00757-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2024] [Indexed: 07/20/2024]
Abstract
Animal sex chromosomes typically carry the upstream sex-determining gene that triggers testis or ovary development and, in some species, are regulated by global dosage compensation in response to functional decay of the Y chromosome. Despite the importance of these pathways, they exhibit striking differences across species, raising fundamental questions regarding the mechanisms underlying their evolutionary turnover. Recent studies of non-model organisms, including insects, reptiles and teleosts, have yielded a broad view of the diversity of sex chromosomes that challenges established theories. Moreover, continued studies in model organisms with recently developed technologies have characterized the dynamics of sex determination and dosage compensation in three-dimensional nuclear space and at single-cell resolution. Here, we synthesize recent insights into sex chromosomes from a variety of species to review their evolutionary dynamics with respect to the canonical model, as well as their diverse mechanisms of regulation.
Collapse
Affiliation(s)
- Zexian Zhu
- Evolutionary and Organismal Biology Research Center and Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Lubna Younas
- Department of Neuroscience and Developmental Biology, University of Vienna, Vienna, Austria
| | - Qi Zhou
- The MOE Key Laboratory of Biosystems Homeostasis & Protection and Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China.
- State Key Laboratory of Transvascular Implantation Devices, The 2nd Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
| |
Collapse
|
3
|
Jay P, Jeffries D, Hartmann FE, Véber A, Giraud T. Why do sex chromosomes progressively lose recombination? Trends Genet 2024; 40:564-579. [PMID: 38677904 DOI: 10.1016/j.tig.2024.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 03/18/2024] [Accepted: 03/19/2024] [Indexed: 04/29/2024]
Abstract
Progressive recombination loss is a common feature of sex chromosomes. Yet, the evolutionary drivers of this phenomenon remain a mystery. For decades, differences in trait optima between sexes (sexual antagonism) have been the favoured hypothesis, but convincing evidence is lacking. Recent years have seen a surge of alternative hypotheses to explain progressive extensions and maintenance of recombination suppression: neutral accumulation of sequence divergence, selection of nonrecombining fragments with fewer deleterious mutations than average, sheltering of recessive deleterious mutations by linkage to heterozygous alleles, early evolution of dosage compensation, and constraints on recombination restoration. Here, we explain these recent hypotheses and dissect their assumptions, mechanisms, and predictions. We also review empirical studies that have brought support to the various hypotheses.
Collapse
Affiliation(s)
- Paul Jay
- Center for GeoGenetics, University of Copenhagen, Copenhagen, Denmark; Université Paris-Saclay, CNRS, AgroParisTech, Laboratoire Ecologie Systématique et Evolution, UMR 8079, Bâtiment 680, 12 route RD128, 91190 Gif-sur-Yvette, France.
| | - Daniel Jeffries
- Division of Evolutionary Ecology, Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland
| | - Fanny E Hartmann
- Université Paris-Saclay, CNRS, AgroParisTech, Laboratoire Ecologie Systématique et Evolution, UMR 8079, Bâtiment 680, 12 route RD128, 91190 Gif-sur-Yvette, France
| | - Amandine Véber
- Université Paris Cité, CNRS, MAP5, F-75006 Paris, France
| | - Tatiana Giraud
- Université Paris-Saclay, CNRS, AgroParisTech, Laboratoire Ecologie Systématique et Evolution, UMR 8079, Bâtiment 680, 12 route RD128, 91190 Gif-sur-Yvette, France
| |
Collapse
|
4
|
Vitale M, Kranjc N, Leigh J, Kyrou K, Courty T, Marston L, Grilli S, Crisanti A, Bernardini F. Y chromosome shredding in Anopheles gambiae: Insight into the cellular dynamics of a novel synthetic sex ratio distorter. PLoS Genet 2024; 20:e1011303. [PMID: 38848445 PMCID: PMC11189259 DOI: 10.1371/journal.pgen.1011303] [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: 01/11/2024] [Revised: 06/20/2024] [Accepted: 05/14/2024] [Indexed: 06/09/2024] Open
Abstract
Despite efforts to explore the genome of the malaria vector Anopheles gambiae, the Y chromosome of this species remains enigmatic. The large number of repetitive and heterochromatic DNA sequences makes the Y chromosome exceptionally difficult to fully assemble, hampering the progress of gene editing techniques and functional studies for this chromosome. In this study, we made use of a bioinformatic platform to identify Y-specific repetitive DNA sequences that served as a target site for a CRISPR/Cas9 system. The activity of Cas9 in the reproductive organs of males caused damage to Y-bearing sperm without affecting their fertility, leading to a strong female bias in the progeny. Cytological investigation allowed us to identify meiotic defects and investigate sperm selection in this new synthetic sex ratio distorter system. In addition, alternative promoters enable us to target the Y chromosome in specific tissues and developmental stages of male mosquitoes, enabling studies that shed light on the role of this chromosome in male gametogenesis. This work paves the way for further insight into the poorly characterised Y chromosome of Anopheles gambiae. Moreover, the sex distorter strain we have generated promises to be a valuable tool for the advancement of studies in the field of developmental biology, with the potential to support the progress of genetic strategies aimed at controlling malaria mosquitoes and other pest species.
Collapse
Affiliation(s)
- Matteo Vitale
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Nace Kranjc
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Jessica Leigh
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Kyrous Kyrou
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Thomas Courty
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Louise Marston
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Silvia Grilli
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Andrea Crisanti
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Federica Bernardini
- Department of Life Sciences, Imperial College London, London, United Kingdom
| |
Collapse
|
5
|
Charlesworth D, Harkess A. Why should we study plant sex chromosomes? THE PLANT CELL 2024; 36:1242-1256. [PMID: 38163640 PMCID: PMC11062472 DOI: 10.1093/plcell/koad278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 10/10/2023] [Indexed: 01/03/2024]
Abstract
Understanding plant sex chromosomes involves studying interactions between developmental and physiological genetics, genome evolution, and evolutionary ecology. We focus on areas of overlap between these. Ideas about how species with separate sexes (dioecious species, in plant terminology) can evolve are even more relevant to plants than to most animal taxa because dioecy has evolved many times from ancestral functionally hermaphroditic populations, often recently. One aim of studying plant sex chromosomes is to discover how separate males and females evolved from ancestors with no such genetic sex-determining polymorphism, and the diversity in the genetic control of maleness vs femaleness. Different systems share some interesting features, and their differences help to understand why completely sex-linked regions may evolve. In some dioecious plants, the sex-determining genome regions are physically small. In others, regions without crossing over have evolved sometimes extensive regions with properties very similar to those of the familiar animal sex chromosomes. The differences also affect the evolutionary changes possible when the environment (or pollination environment, for angiosperms) changes, as dioecy is an ecologically risky strategy for sessile organisms. Dioecious plants have repeatedly reverted to cosexuality, and hermaphroditic strains of fruit crops such as papaya and grapes are desired by plant breeders. Sex-linked regions are predicted to become enriched in genes with sex differences in expression, especially when higher expression benefits one sex function but harms the other. Such trade-offs may be important for understanding other plant developmental and physiological processes and have direct applications in plant breeding.
Collapse
Affiliation(s)
- Deborah Charlesworth
- Institute of Ecology and Evolution, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Alex Harkess
- HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA
| |
Collapse
|
6
|
Muralidhar P, Coop G. Polygenic response of sex chromosomes to sexual antagonism. Evolution 2024; 78:539-554. [PMID: 38153370 PMCID: PMC10903542 DOI: 10.1093/evolut/qpad231] [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: 03/22/2023] [Revised: 11/30/2023] [Accepted: 12/22/2023] [Indexed: 12/29/2023]
Abstract
Sexual antagonism occurs when males and females differ in their phenotypic fitness optima but are constrained in their evolution to these optima because of their shared genome. The sex chromosomes, which have distinct evolutionary "interests" relative to the autosomes, are theorized to play an important role in sexually antagonistic conflict. However, the evolutionary responses of sex chromosomes and autosomes have usually been considered independently, that is, via contrasting the response of a gene located on either an X chromosome or an autosome. Here, we study the coevolutionary response of the X chromosome and autosomes to sexually antagonistic selection acting on a polygenic phenotype. We model a phenotype initially under stabilizing selection around a single optimum, followed by a sudden divergence of the male and female optima. We find that, in the absence of dosage compensation, the X chromosome promotes evolution toward the female optimum, inducing coevolutionary male-biased responses on the autosomes. Dosage compensation obscures the female-biased interests of the X, causing it to contribute equally to male and female phenotypic change. We further demonstrate that fluctuations in an adaptive landscape can generate prolonged intragenomic conflict and accentuate the differential responses of the X and autosomes to this conflict.
Collapse
Affiliation(s)
- Pavitra Muralidhar
- Center for Population Biology, University of California, Davis, CA, United States
- Department of Evolution and Ecology, University of California, Davis, CA, United States
- Department of Ecology and Evolution, University of Chicago, Chicago, IL, United States
| | - Graham Coop
- Center for Population Biology, University of California, Davis, CA, United States
- Department of Evolution and Ecology, University of California, Davis, CA, United States
| |
Collapse
|
7
|
Kitano J, Ansai S, Takehana Y, Yamamoto Y. Diversity and Convergence of Sex-Determination Mechanisms in Teleost Fish. Annu Rev Anim Biosci 2024; 12:233-259. [PMID: 37863090 DOI: 10.1146/annurev-animal-021122-113935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2023]
Abstract
Sexual reproduction is prevalent across diverse taxa. However, sex-determination mechanisms are so diverse that even closely related species often differ in sex-determination systems. Teleost fish is a taxonomic group with frequent turnovers of sex-determining mechanisms and thus provides us with great opportunities to investigate the molecular and evolutionary mechanisms underlying the turnover of sex-determining systems. Here, we compile recent studies on the diversity of sex-determination mechanisms in fish. We demonstrate that genes in the TGF-β signaling pathway are frequently used for master sex-determining (MSD) genes. MSD genes arise via two main mechanisms, duplication-and-transposition and allelic mutations, with a few exceptions. We also demonstrate that temperature influences sex determination in many fish species, even those with sex chromosomes, with higher temperatures inducing differentiation into males in most cases. Finally, we review theoretical models for the turnover of sex-determining mechanisms and discuss what questions remain elusive.
Collapse
Affiliation(s)
- Jun Kitano
- Ecological Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan;
| | - Satoshi Ansai
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
- Graduate School of Agriculture, Kyoto University, Kyoto, Japan;
| | - Yusuke Takehana
- Faculty of Bio-Science, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan;
| | - Yoji Yamamoto
- Department of Marine Biosciences, Tokyo University of Marine Science and Technology, Tokyo, Japan;
| |
Collapse
|
8
|
Shaw DE, Naftaly AS, White MA. Positive Selection Drives cis-regulatory Evolution Across the Threespine Stickleback Y Chromosome. Mol Biol Evol 2024; 41:msae020. [PMID: 38306314 PMCID: PMC10899008 DOI: 10.1093/molbev/msae020] [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: 08/11/2023] [Revised: 12/31/2023] [Accepted: 01/24/2024] [Indexed: 02/04/2024] Open
Abstract
Allele-specific gene expression evolves rapidly on heteromorphic sex chromosomes. Over time, the accumulation of mutations on the Y chromosome leads to widespread loss of gametolog expression, relative to the X chromosome. It remains unclear if expression evolution on degrading Y chromosomes is primarily driven by mutations that accumulate through processes of selective interference, or if positive selection can also favor the down-regulation of coding regions on the Y chromosome that contain deleterious mutations. Identifying the relative rates of cis-regulatory sequence evolution across Y chromosomes has been challenging due to the limited number of reference assemblies. The threespine stickleback (Gasterosteus aculeatus) Y chromosome is an excellent model to identify how regulatory mutations accumulate on Y chromosomes due to its intermediate state of divergence from the X chromosome. A large number of Y-linked gametologs still exist across 3 differently aged evolutionary strata to test these hypotheses. We found that putative enhancer regions on the Y chromosome exhibited elevated substitution rates and decreased polymorphism when compared to nonfunctional sites, like intergenic regions and synonymous sites. This suggests that many cis-regulatory regions are under positive selection on the Y chromosome. This divergence was correlated with X-biased gametolog expression, indicating the loss of expression from the Y chromosome may be favored by selection. Our findings provide evidence that Y-linked cis-regulatory regions exhibit signs of positive selection quickly after the suppression of recombination and allow comparisons with recent theoretical models that suggest the rapid divergence of regulatory regions may be favored to mask deleterious mutations on the Y chromosome.
Collapse
Affiliation(s)
- Daniel E Shaw
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | | | - Michael A White
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| |
Collapse
|
9
|
Behrens KA, Zimmermann H, Blažek R, Reichard M, Koblmüller S, Kocher TD. Turnover of sex chromosomes in the Lake Tanganyika cichlid tribe Tropheini (Teleostei: Cichlidae). Sci Rep 2024; 14:2471. [PMID: 38291228 PMCID: PMC10828463 DOI: 10.1038/s41598-024-53021-3] [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: 07/14/2023] [Accepted: 01/25/2024] [Indexed: 02/01/2024] Open
Abstract
Sex chromosome replacement is frequent in many vertebrate clades, including fish, frogs, and lizards. In order to understand the mechanisms responsible for sex chromosome turnover and the early stages of sex chromosome divergence, it is necessary to study lineages with recently evolved sex chromosomes. Here we examine sex chromosome evolution in a group of African cichlid fishes (tribe Tropheini) which began to diverge from one another less than 4 MYA. We have evidence for a previously unknown sex chromosome system, and preliminary indications of several additional systems not previously reported in this group. We find a high frequency of sex chromosome turnover and estimate a minimum of 14 turnovers in this tribe. We date the origin of the most common sex determining system in this tribe (XY-LG5/19) near the base of one of two major sub-clades of this tribe, about 3.4 MY ago. Finally, we observe variation in the size of one sex-determining region that suggests independent evolution of evolutionary strata in species with a shared sex-determination system. Our results illuminate the rapid rate of sex chromosome turnover in the tribe Tropheini and set the stage for further studies of the dynamics of sex chromosome evolution in this group.
Collapse
Affiliation(s)
- Kristen A Behrens
- Department of Biology, University of Maryland, College Park, MD, 20742, USA.
| | - Holger Zimmermann
- Institute of Vertebrate Biology, Czech Academy of Sciences, Květná 8, 603 00, Brno, Czech Republic
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010, Graz, Austria
| | - Radim Blažek
- Institute of Vertebrate Biology, Czech Academy of Sciences, Květná 8, 603 00, Brno, Czech Republic
| | - Martin Reichard
- Institute of Vertebrate Biology, Czech Academy of Sciences, Květná 8, 603 00, Brno, Czech Republic
- Department of Ecology and Vertebrate Zoology, University of Łódź, Łódź, Poland
| | - Stephan Koblmüller
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010, Graz, Austria
| | - Thomas D Kocher
- Department of Biology, University of Maryland, College Park, MD, 20742, USA
| |
Collapse
|
10
|
Filatov DA. Evolution of a plant sex chromosome driven by expanding pericentromeric recombination suppression. Sci Rep 2024; 14:1373. [PMID: 38228625 DOI: 10.1038/s41598-024-51153-0] [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: 09/29/2023] [Accepted: 01/01/2024] [Indexed: 01/18/2024] Open
Abstract
Recombination suppression around sex-determining gene(s) is a key step in evolution of sex chromosomes, but it is not well understood how it evolves. Recently evolved sex-linked regions offer an opportunity to understand the mechanisms of recombination cessation. This paper analyses such a region on Silene latifolia (Caryophyllaceae) sex chromosomes, where recombination was suppressed in the last 120 thousand years ("stratum 3"). Locating the boundaries of the stratum 3 in S. latifolia genome sequence revealed that this region is far larger than assumed previously-it is about 14 Mb long and includes 202 annotated genes. A gradient of X:Y divergence detected in the stratum 3, with divergence increasing proximally, indicates gradual recombination cessation, possibly caused by expansion of pericentromeric recombination suppression (PRS) into the pseudoautosomal region. Expansion of PRS was also the likely cause for the formation of the older stratum 2 on S. latifolia sex chromosomes. The role of PRS in sex chromosome evolution has been underappreciated, but it may be a significant factor, especially in the species with large chromosomes where PRS is often extensive.
Collapse
Affiliation(s)
- Dmitry A Filatov
- Department of Biology, University of Oxford, Oxford, OX1 3RB, UK.
| |
Collapse
|
11
|
Biedler JK, Aryan A, Qi Y, Wang A, Martinson EO, Hartman DA, Yang F, Sharma A, Morton KS, Potters M, Chen C, Dobson SL, Ebel GD, Kading RC, Paulson S, Xue RD, Strand MR, Tu Z. On the Origin and Evolution of the Mosquito Male-determining Factor Nix. Mol Biol Evol 2024; 41:msad276. [PMID: 38128148 PMCID: PMC10798136 DOI: 10.1093/molbev/msad276] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 12/02/2023] [Accepted: 12/08/2023] [Indexed: 12/23/2023] Open
Abstract
The mosquito family Culicidae is divided into 2 subfamilies named the Culicinae and Anophelinae. Nix, the dominant male-determining factor, has only been found in the culicines Aedes aegypti and Aedes albopictus, 2 important arboviral vectors that belong to the subgenus Stegomyia. Here we performed sex-specific whole-genome sequencing and RNAseq of divergent mosquito species and explored additional male-inclusive datasets to investigate the distribution of Nix. Except for the Culex genus, Nix homologs were found in all species surveyed from the Culicinae subfamily, including 12 additional species from 3 highly divergent tribes comprising 4 genera, suggesting Nix originated at least 133 to 165 million years ago (MYA). Heterologous expression of 1 of 3 divergent Nix open reading frames (ORFs) in Ae. aegypti resulted in partial masculinization of genetic females as evidenced by morphology and doublesex splicing. Phylogenetic analysis suggests Nix is related to femaleless (fle), a recently described intermediate sex-determining factor found exclusively in anopheline mosquitoes. Nix from all species has a conserved structure, including 3 RNA-recognition motifs (RRMs), as does fle. However, Nix has evolved at a much faster rate than fle. The RRM3 of both Nix and fle are distantly related to the single RRM of a widely distributed and conserved splicing factor transformer-2 (tra2). The RRM3-based phylogenetic analysis suggests this domain in Nix and fle may have evolved from tra2 or a tra2-related gene in a common ancestor of mosquitoes. Our results provide insights into the evolution of sex determination in mosquitoes and will inform broad applications of mosquito-control strategies based on manipulating sex ratios toward nonbiting males.
Collapse
Affiliation(s)
- James K Biedler
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA
| | - Azadeh Aryan
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA
| | - Yumin Qi
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA
| | - Aihua Wang
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA
| | - Ellen O Martinson
- Department of Entomology, University of Georgia, Athens, GA 30602, USA
| | - Daniel A Hartman
- Center for Vector-borne Infectious Diseases, Department of Microbiology Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Fan Yang
- Department of Entomology, Virginia Tech, Blacksburg, VA 24061, USA
| | - Atashi Sharma
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA
| | - Katherine S Morton
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA
| | - Mark Potters
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA
| | - Chujia Chen
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA
- Genetics Bioinformatics and Computational Biology PhD program, Virginia Tech, Blacksburg, VA 24061, USA
| | - Stephen L Dobson
- Department of Entomology, University of Kentucky, Lexington, KY 40503, USA
- MosquitoMate, Inc., Lexington, KY 40502, USA
| | - Gregory D Ebel
- Center for Vector-borne Infectious Diseases, Department of Microbiology Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Rebekah C Kading
- Center for Vector-borne Infectious Diseases, Department of Microbiology Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Sally Paulson
- Department of Entomology, Virginia Tech, Blacksburg, VA 24061, USA
| | - Rui-De Xue
- Anastasia Mosquito Control District, St. Augustine, FL 32092, USA
| | - Michael R Strand
- Department of Entomology, University of Georgia, Athens, GA 30602, USA
| | - Zhijian Tu
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA
- Genetics Bioinformatics and Computational Biology PhD program, Virginia Tech, Blacksburg, VA 24061, USA
| |
Collapse
|
12
|
Fedder J, Fagerberg C, Jørgensen MW, Gravholt CH, Berglund A, Knudsen UB, Skakkebæk A. Complete or partial loss of the Y chromosome in an unselected cohort of 865 non-vasectomized, azoospermic men. Basic Clin Androl 2023; 33:37. [PMID: 38093178 PMCID: PMC10720143 DOI: 10.1186/s12610-023-00212-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 10/26/2023] [Indexed: 12/17/2023] Open
Abstract
BACKGROUND Structural abnormalities as well as minor variations of the Y chromosome may cause disorders of sex differentiation or, more frequently, azoospermia. This study aimed to determine the prevalence of loss of Y chromosome material within the spectrum ranging from small microdeletions in the azoospermia factor region (AZF) to complete loss of the Y chromosome in azoospermic men. RESULTS Eleven of 865 azoospermic men (1.3%) collected from 1997 to 2022 were found to have a karyotype including a 45,X cell line. Two had a pure 45,X karyotype and nine had a 45,X/46,XY mosaic karyotype. The AZF region, or part of it, was deleted in eight of the nine men with a structural abnormal Y-chromosome. Seven men had a karyotype with a structural abnormal Y chromosome in a non-mosaic form. In addition, Y chromosome microdeletions were found in 34 men with a structural normal Y chromosome. No congenital malformations were detected by echocardiography and ultrasonography of the kidneys of the 11 men with a 45,X mosaic or non-mosaic cell line. CONCLUSIONS In men with azoospermia, Y chromosome loss ranging from small microdeletions to complete loss of the Y chromosome was found in 6.1% (53/865). Partial AZFb microdeletions may give a milder testicular phenotype compared to complete AZFb microdeletions.
Collapse
Affiliation(s)
- J Fedder
- Centre of Andrology & Fertility Clinic, Odense University Hospital, Kløvervænget 23, DK-5000, Odense, Denmark.
- Department of Clinical Medicine, University of Southern Denmark, Odense, Denmark.
- Fertility Clinic, Horsens Hospital, Horsens, Denmark.
| | - C Fagerberg
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
| | - M W Jørgensen
- Department of Clinical Genetics, Lillebaelt Hospital, Vejle, Denmark
| | - C H Gravholt
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
- Department of Endocrinology, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - A Berglund
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | - U B Knudsen
- Fertility Clinic, Horsens Hospital, Horsens, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - A Skakkebæk
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| |
Collapse
|
13
|
Scarparo G, Palanchon M, Brelsford A, Purcell J. Social antagonism facilitates supergene expansion in ants. Curr Biol 2023; 33:5085-5095.e4. [PMID: 37979579 DOI: 10.1016/j.cub.2023.10.049] [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: 04/26/2023] [Revised: 08/07/2023] [Accepted: 10/25/2023] [Indexed: 11/20/2023]
Abstract
Antagonistic selection has long been considered a major driver of the formation and expansion of sex chromosomes. For example, sexually antagonistic variation on an autosome can select for suppressed recombination between that autosome and the sex chromosome, leading to a neo-sex chromosome. Autosomal supergenes, chromosomal regions containing tightly linked variants affecting the same complex trait, share similarities with sex chromosomes, raising the possibility that sex chromosome evolution models can explain the evolution of genome structure and recombination in other contexts. We tested this premise in a Formica ant species, wherein we identified four supergene haplotypes on chromosome 3 underlying colony social organization and sex ratio. We discovered a novel rearranged supergene variant (9r) on chromosome 9 underlying queen miniaturization. The 9r is in strong linkage disequilibrium with one chromosome 3 haplotype (P2) found in multi-queen (polygyne) colonies. We suggest that queen miniaturization is strongly disfavored in the single-queen (monogyne) background and is thus socially antagonistic. As such, divergent selection experienced by ants living in alternative social "environments" (monogyne and polygyne) may have contributed to the emergence of a genetic polymorphism on chromosome 9 and associated queen-size dimorphism. Consequently, an ancestral polygyne-associated haplotype may have expanded to include the polymorphism on chromosome 9, resulting in a larger region of suppressed recombination spanning two chromosomes. This process is analogous to the formation of neo-sex chromosomes and consistent with models of expanding regions of suppressed recombination. We propose that miniaturized queens, 16%-20% smaller than queens without 9r, could be incipient intraspecific social parasites.
Collapse
Affiliation(s)
- Giulia Scarparo
- Department of Entomology, University of California, Riverside, 165 Entomology Bldg. Citrus Drive, Riverside, CA 92521, USA.
| | - Marie Palanchon
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, 2710 Life Science Bldg., Riverside, CA 92521, USA
| | - Alan Brelsford
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, 2710 Life Science Bldg., Riverside, CA 92521, USA
| | - Jessica Purcell
- Department of Entomology, University of California, Riverside, 165 Entomology Bldg. Citrus Drive, Riverside, CA 92521, USA.
| |
Collapse
|
14
|
Berdan EL, Barton NH, Butlin R, Charlesworth B, Faria R, Fragata I, Gilbert KJ, Jay P, Kapun M, Lotterhos KE, Mérot C, Durmaz Mitchell E, Pascual M, Peichel CL, Rafajlović M, Westram AM, Schaeffer SW, Johannesson K, Flatt T. How chromosomal inversions reorient the evolutionary process. J Evol Biol 2023; 36:1761-1782. [PMID: 37942504 DOI: 10.1111/jeb.14242] [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: 05/05/2023] [Revised: 09/13/2023] [Accepted: 10/05/2023] [Indexed: 11/10/2023]
Abstract
Inversions are structural mutations that reverse the sequence of a chromosome segment and reduce the effective rate of recombination in the heterozygous state. They play a major role in adaptation, as well as in other evolutionary processes such as speciation. Although inversions have been studied since the 1920s, they remain difficult to investigate because the reduced recombination conferred by them strengthens the effects of drift and hitchhiking, which in turn can obscure signatures of selection. Nonetheless, numerous inversions have been found to be under selection. Given recent advances in population genetic theory and empirical study, here we review how different mechanisms of selection affect the evolution of inversions. A key difference between inversions and other mutations, such as single nucleotide variants, is that the fitness of an inversion may be affected by a larger number of frequently interacting processes. This considerably complicates the analysis of the causes underlying the evolution of inversions. We discuss the extent to which these mechanisms can be disentangled, and by which approach.
Collapse
Affiliation(s)
- Emma L Berdan
- Bioinformatics Core, Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Nicholas H Barton
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Roger Butlin
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
- Ecology and Evolutionary Biology, School of Bioscience, The University of Sheffield, Sheffield, UK
| | - Brian Charlesworth
- Institute of Ecology and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Rui Faria
- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal
- BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Vairão, Portugal
| | - Inês Fragata
- CHANGE - Global Change and Sustainability Institute/Animal Biology Department, cE3c - Center for Ecology, Evolution and Environmental Changes, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | | | - Paul Jay
- Center for GeoGenetics, University of Copenhagen, Copenhagen, Denmark
| | - Martin Kapun
- Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
- Central Research Laboratories, Natural History Museum of Vienna, Vienna, Austria
| | - Katie E Lotterhos
- Department of Marine and Environmental Sciences, Northeastern University, Boston, Massachusetts, USA
| | - Claire Mérot
- UMR 6553 Ecobio, Université de Rennes, OSUR, CNRS, Rennes, France
| | - Esra Durmaz Mitchell
- Department of Biology, University of Fribourg, Fribourg, Switzerland
- Functional Genomics & Metabolism Research Unit, Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Marta Pascual
- Departament de Genètica, Microbiologia i Estadística, Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Barcelona, Spain
| | - Catherine L Peichel
- Division of Evolutionary Ecology, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - Marina Rafajlović
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
- Linnaeus Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
| | - Anja M Westram
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Stephen W Schaeffer
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Kerstin Johannesson
- Linnaeus Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
- Tjärnö Marine Laboratory, Department of Marine Sciences, University of Gothenburg, Strömstad, Sweden
| | - Thomas Flatt
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| |
Collapse
|
15
|
McDaniel SF. Divergent outcomes of genetic conflict on the UV sex chromosomes of Marchantia polymorpha and Ceratodon purpureus. Curr Opin Genet Dev 2023; 83:102129. [PMID: 37864936 DOI: 10.1016/j.gde.2023.102129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 09/22/2023] [Accepted: 09/24/2023] [Indexed: 10/23/2023]
Abstract
In species with separate sexes, the genome must produce two distinct developmental programs. Sexually dimorphic development may be controlled by either sex-limited loci or biased expression of loci transmitted through both sexes. Variation in the gene content of sex-limited chromosomes demonstrates that eukaryotic species differ markedly in the roles of these two mechanisms in governing sexual dimorphism. The bryophyte model systems Marchantia polymorpha and Ceratodon purpureus provide a particularly striking contrast. Although both species possess a haploid UV sex chromosome system, in which females carry a U chromosome and males carry a V, M. polymorpha relies on biased autosomal expression, while in C. purpureus, sex-linked genes drive dimorphism. Framing these genetic architectures as divergent outcomes of genetic conflict highlights comparative genomic analyses to better understand the evolution of sexual dimorphism.
Collapse
Affiliation(s)
- Stuart F McDaniel
- Biology Department, University of Florida, Gainesville, FL 32611-8525, USA.
| |
Collapse
|
16
|
Kazama Y, Kobayashi T, Filatov DA. Evolution of sex-determination in dioecious plants: From active Y to X/A balance? Bioessays 2023; 45:e2300111. [PMID: 37694687 DOI: 10.1002/bies.202300111] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/28/2023] [Accepted: 08/28/2023] [Indexed: 09/12/2023]
Abstract
Sex chromosomes in plants have been known for a century, but only recently have we begun to understand the mechanisms behind sex determination in dioecious plants. Here, we discuss evolution of sex determination, focusing on Silene latifolia, where evolution of separate sexes is consistent with the classic "two mutations" model-a loss of function male sterility mutation and a gain of function gynoecium suppression mutation, which turned an ancestral hermaphroditic population into separate males and females. Interestingly, the gynoecium suppression function in S. latifolia evolved via loss of function in at least two sex-linked genes and works via gene dosage balance between sex-linked, and autosomal genes. This system resembles X/A-ratio-based sex determination systems in Drosophila and Rumex, and could represent a steppingstone in the evolution of X/A-ratio-based sex determination from an active Y system.
Collapse
Affiliation(s)
- Yusuke Kazama
- Graduate school of Bioscience and Biotechnology, Fukui Prefectural University, Eiheiji-cho, Fukui, Japan
- RIKEN Nishina Center, Wako, Saitama, Japan
| | - Taiki Kobayashi
- Graduate school of Bioscience and Biotechnology, Fukui Prefectural University, Eiheiji-cho, Fukui, Japan
| | | |
Collapse
|
17
|
Cauret CMS, Jordan DC, Kukoly LM, Burton SR, Anele EU, Kwiecien JM, Gansauge MT, Senthillmohan S, Greenbaum E, Meyer M, Horb ME, Evans BJ. Functional dissection and assembly of a small, newly evolved, W chromosome-specific genomic region of the African clawed frog Xenopus laevis. PLoS Genet 2023; 19:e1010990. [PMID: 37792893 PMCID: PMC10578606 DOI: 10.1371/journal.pgen.1010990] [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: 03/07/2023] [Revised: 10/16/2023] [Accepted: 09/20/2023] [Indexed: 10/06/2023] Open
Abstract
Genetic triggers for sex determination are frequently co-inherited with other linked genes that may also influence one or more sex-specific phenotypes. To better understand how sex-limited regions evolve and function, we studied a small W chromosome-specific region of the frog Xenopus laevis that contains only three genes (dm-w, scan-w, ccdc69-w) and that drives female differentiation. Using gene editing, we found that the sex-determining function of this region requires dm-w but that scan-w and ccdc69-w are not essential for viability, female development, or fertility. Analysis of mesonephros+gonad transcriptomes during sexual differentiation illustrates masculinization of the dm-w knockout transcriptome, and identifies mostly non-overlapping sets of differentially expressed genes in separate knockout lines for each of these three W-specific gene compared to wildtype sisters. Capture sequencing of almost all Xenopus species and PCR surveys indicate that the female-determining function of dm-w is present in only a subset of species that carry this gene. These findings map out a dynamic evolutionary history of a newly evolved W chromosome-specific genomic region, whose components have distinctive functions that frequently degraded during Xenopus diversification, and evidence the evolutionary consequences of recombination suppression.
Collapse
Affiliation(s)
- Caroline M. S. Cauret
- Biology Department, McMaster University, Hamilton, Ontario, Canada
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
| | - Danielle C. Jordan
- Eugene Bell Center for Regenerative Biology and Tissue Engineering and National Xenopus Resource, Marine Biological Laboratory, Woods Hole, Massachusetts United States of America
- The School of Biological Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | | | - Sarah R. Burton
- Eugene Bell Center for Regenerative Biology and Tissue Engineering and National Xenopus Resource, Marine Biological Laboratory, Woods Hole, Massachusetts United States of America
| | - Emmanuela U. Anele
- Biology Department, McMaster University, Hamilton, Ontario, Canada
- Department Zoology, Ahmadu Bello University, Zaria, Nigeria
| | - Jacek M. Kwiecien
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Marie-Theres Gansauge
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | | | - Eli Greenbaum
- Department of Biological Sciences, The University of Texas at El Paso, El Paso, Texas, United States of America
| | - Matthias Meyer
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Marko E. Horb
- Eugene Bell Center for Regenerative Biology and Tissue Engineering and National Xenopus Resource, Marine Biological Laboratory, Woods Hole, Massachusetts United States of America
| | - Ben J. Evans
- Biology Department, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
18
|
Fong LJM, Darolti I, Metzger DCH, Morris J, Lin Y, Sandkam BA, Mank JE. Parsimony and Poeciliid Sex Chromosome Evolution. Genome Biol Evol 2023; 15:evad128. [PMID: 37670515 PMCID: PMC10480581 DOI: 10.1093/gbe/evad128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2023] [Indexed: 09/07/2023] Open
Affiliation(s)
- Lydia J M Fong
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Iulia Darolti
- Department of Ecology and Evolution, University of Lausanne, Switzerland
| | - David C H Metzger
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Jake Morris
- School of Biological Sciences, University of Bristol, United Kingdom
| | - Yuying Lin
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Benjamin A Sandkam
- Department of Neurobiology and Behavior, Cornell University, Ithaca, New York, USA
| | - Judith E Mank
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| |
Collapse
|
19
|
Charlesworth D, Hastings A, Graham C. Can a Y Chromosome Degenerate in an Evolutionary Instant? A Commentary on Fong et al. 2023. Genome Biol Evol 2023; 15:evad105. [PMID: 37290043 PMCID: PMC10480580 DOI: 10.1093/gbe/evad105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/29/2023] [Accepted: 06/01/2023] [Indexed: 06/10/2023] Open
Abstract
It is well known that the Y chromosomes of Drosophila and mammals and the W chromosomes of birds carry only small fractions of the genes carried by the homologous X or Z chromosomes, and this "genetic degeneration" is associated with loss of recombination between the sex chromosome pair. However, it is still not known how much evolutionary time is needed to reach such nearly complete degeneration. The XY pair of species in a group of closely related poecilid fish is homologous but has been found to have either nondegenerated or completely degenerated Y chromosomes. We evaluate evidence described in a recent paper and show that the available data cast doubt on the view that degeneration has been extraordinarily rapid in the latter (Micropoecilia species).
Collapse
Affiliation(s)
- Deborah Charlesworth
- Institute of Ecology and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Abigail Hastings
- Institute of Ecology and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Chay Graham
- Institute of Ecology and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| |
Collapse
|
20
|
Smith SH, Hsiung K, Böhne A. Evaluating the role of sexual antagonism in the evolution of sex chromosomes: new data from fish. Curr Opin Genet Dev 2023; 81:102078. [PMID: 37379742 DOI: 10.1016/j.gde.2023.102078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 06/07/2023] [Accepted: 06/07/2023] [Indexed: 06/30/2023]
Abstract
The recent increase in available molecular and genomic data for diverse taxa helps to shed new light on long-standing theories. Research into sex chromosome evolution has particularly benefited from a growing number of studies of fish, motivated by their highly diverse mechanisms of sex determination. Sexual antagonism is regularly cited as an influential force in sex chromosome emergence; however, this so far proves difficult to demonstrate. In this review, we highlight recent developments in the investigation of sexual antagonism in sex chromosome research in fish. We find strong emphasis placed on study-organism specific genomic features and patterns of recombination, rather than evidence for a comprehensive role of sexual antagonism. In this light, we discuss the alternative models of sex chromosome evolution. We conclude that fish represents a key resource for further research, provided attention is given to species-specific effects while simultaneously integrating comparative studies across taxa for a vital and comprehensive understanding of sex chromosome evolution and investigation of proposed models.
Collapse
Affiliation(s)
- Sophie Helen Smith
- Centre for Molecular Biodiversity Research, Leibniz Institute for the Analysis of Biodiversity Change, Museum Koenig Bonn, Adenauerallee 127, 53113 Bonn, Germany. https://twitter.com/@shg_smith
| | - Kevin Hsiung
- Centre for Molecular Biodiversity Research, Leibniz Institute for the Analysis of Biodiversity Change, Museum Koenig Bonn, Adenauerallee 127, 53113 Bonn, Germany. https://twitter.com/@KevinKHsiung
| | - Astrid Böhne
- Centre for Molecular Biodiversity Research, Leibniz Institute for the Analysis of Biodiversity Change, Museum Koenig Bonn, Adenauerallee 127, 53113 Bonn, Germany.
| |
Collapse
|
21
|
Yue J, Krasovec M, Kazama Y, Zhang X, Xie W, Zhang S, Xu X, Kan B, Ming R, Filatov DA. The origin and evolution of sex chromosomes, revealed by sequencing of the Silene latifolia female genome. Curr Biol 2023:S0960-9822(23)00678-4. [PMID: 37290443 DOI: 10.1016/j.cub.2023.05.046] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 04/07/2023] [Accepted: 05/19/2023] [Indexed: 06/10/2023]
Abstract
White campion (Silene latifolia, Caryophyllaceae) was the first vascular plant where sex chromosomes were discovered. This species is a classic model for studies on plant sex chromosomes due to presence of large, clearly distinguishable X and Y chromosomes that originated de novo about 11 million years ago (mya), but lack of genomic resources for this relatively large genome (∼2.8 Gb) remains a significant hurdle. Here we report S. latifolia female genome assembly integrated with sex-specific genetic maps of this species, focusing on sex chromosomes and their evolution. The analysis reveals a highly heterogeneous recombination landscape with strong reduction in recombination rate in the central parts of all chromosomes. Recombination on the X chromosome in female meiosis primarily occurs at the very ends, and over 85% of the X chromosome length is located in a massive (∼330 Mb) gene-poor, rarely recombining pericentromeric region (Xpr). The results indicate that the non-recombining region on the Y chromosome (NRY) initially evolved in a relatively small (∼15 Mb), actively recombining region at the end of the q-arm, possibly as a result of inversion on the nascent X chromosome. The NRY expanded about 6 mya via linkage between the Xpr and the sex-determining region, which may have been caused by expanding pericentromeric recombination suppression on the X chromosome. These findings shed light on the origin of sex chromosomes in S. latifolia and yield genomic resources to assist ongoing and future investigations into sex chromosome evolution.
Collapse
Affiliation(s)
- Jingjing Yue
- Centre for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Marc Krasovec
- Department of Biology, University of Oxford, Oxford OX1 3RB, UK; Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, 66650 Banyuls-sur-Mer, France
| | - Yusuke Kazama
- Department of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Kenjojima, Matsuoka, Eiheiji-cho, Fukui 910-1195, Japan
| | - Xingtan Zhang
- Centre for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518100, China
| | - Wangyang Xie
- Centre for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shencheng Zhang
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518100, China
| | - Xiuming Xu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen 361100, China
| | - Baolin Kan
- Centre for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Ray Ming
- Centre for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Dmitry A Filatov
- Department of Biology, University of Oxford, Oxford OX1 3RB, UK.
| |
Collapse
|
22
|
Hyden B, Zou J, Wilkerson DG, Carlson CH, Robles AR, DiFazio SP, Smart LB. Structural variation of a sex-linked region confers monoecy and implicates GATA15 as a master regulator of sex in Salix purpurea. THE NEW PHYTOLOGIST 2023; 238:2512-2523. [PMID: 36866707 DOI: 10.1111/nph.18853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 02/21/2023] [Indexed: 05/19/2023]
Abstract
The Salicaceae, including Populus and Salix, are dioecious perennials that utilize different sex determination systems. This family provides a useful system to better understand the evolution of dioecy and sex chromosomes. Here, a rare monoecious genotype of Salix purpurea, 94003, was self- and cross-pollinated and progeny sex ratios were used to test hypotheses on possible mechanisms of sex determination. To delimit genomic regions associated with monoecious expression, the 94003 genome sequence was assembled and DNA- and RNA-Seq of progeny inflorescences was performed. Based on alignments of progeny shotgun DNA sequences to the haplotype-resolved monoecious 94003 genome assembly and reference male and female genomes, a 1.15 Mb sex-linked region on Chr15W was confirmed to be absent in monecious plants. Inheritance of this structural variation is responsible for the loss of a male-suppressing function in what would otherwise be genetic females (ZW), resulting in monoecy (ZWH or WWH ), or lethality, if homozygous (WH WH ). We present a refined, two-gene sex determination model for Salix purpurea, mediated by ARR17 and GATA15 that is different from the single-gene ARR17-mediated system in the related genus Populus.
Collapse
Affiliation(s)
- Brennan Hyden
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, 14456, USA
| | - Junzhu Zou
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, 14456, USA
- Research Institute of Forestry, Chinese Academy of Forestry, Dongxiaofu No. 1, Haidian District, Beijing, 100091, China
| | - Dustin G Wilkerson
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, 14456, USA
| | - Craig H Carlson
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, 14456, USA
- Cereal Crops Research Unit, Edward T. Schafer Agricultural Research Center, USDA-ARS, Fargo, ND, 58102, USA
| | - Ayiana Rivera Robles
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, 14456, USA
| | - Stephen P DiFazio
- Department of Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - Lawrence B Smart
- Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech, Geneva, NY, 14456, USA
| |
Collapse
|
23
|
Masuda K, Akagi T. Evolution of sex in crops: recurrent scrap and rebuild. BREEDING SCIENCE 2023; 73:95-107. [PMID: 37404348 PMCID: PMC10316312 DOI: 10.1270/jsbbs.22082] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 11/20/2022] [Indexed: 07/06/2023]
Abstract
Sexuality is the main strategy for maintaining genetic diversity within a species. In flowering plants (angiosperms), sexuality is derived from ancestral hermaphroditism and multiple sexualities can be expressed in an individual. The mechanisms conferring chromosomal sex determination in plants (or dioecy) have been studied for over a century by both biologists and agricultural scientists, given the importance of this field for crop cultivation and breeding. Despite extensive research, the sex determining gene(s) in plants had not been identified until recently. In this review, we dissect plant sex evolution and determining systems, with a focus on crop species. We introduced classic studies with theoretical, genetic, and cytogenic approaches, as well as more recent research using advanced molecular and genomic techniques. Plants have undergone very frequent transitions into, and out of, dioecy. Although only a few sex determinants have been identified in plants, an integrative viewpoint on their evolutionary trends suggests that recurrent neofunctionalization events are potentially common, in a "scrap and (re)build" cycle. We also discuss the potential association between crop domestication and transitions in sexual systems. We focus on the contribution of duplication events, which are particularly frequent in plant taxa, as a trigger for the creation of new sexual systems.
Collapse
Affiliation(s)
- Kanae Masuda
- Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan
| | - Takashi Akagi
- Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan
- JST, PRESTO, Kawaguchi, Saitama 332-0012, Japan
| |
Collapse
|
24
|
Charlesworth D. Why and how do Y chromosome stop recombining? J Evol Biol 2023; 36:632-636. [PMID: 36683363 DOI: 10.1111/jeb.14137] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/21/2022] [Accepted: 11/24/2022] [Indexed: 01/24/2023]
|
25
|
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.
Collapse
|
26
|
Vittorelli N, Rodríguez de la Vega RC, Snirc A, Levert E, Gautier V, Lalanne C, De Filippo E, Gladieux P, Guillou S, Zhang Y, Tejomurthula S, Grigoriev IV, Debuchy R, Silar P, Giraud T, Hartmann FE. Stepwise recombination suppression around the mating-type locus in an ascomycete fungus with self-fertile spores. PLoS Genet 2023; 19:e1010347. [PMID: 36763677 PMCID: PMC9949647 DOI: 10.1371/journal.pgen.1010347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 02/23/2023] [Accepted: 01/17/2023] [Indexed: 02/12/2023] Open
Abstract
Recombination is often suppressed at sex-determining loci in plants and animals, and at self-incompatibility or mating-type loci in plants and fungi. In fungal ascomycetes, recombination suppression around the mating-type locus is associated with pseudo-homothallism, i.e. the production of self-fertile dikaryotic sexual spores carrying the two opposite mating types. This has been well studied in two species complexes from different families of Sordariales: Podospora anserina and Neurospora tetrasperma. However, it is unclear whether this intriguing association holds in other species. We show here that Schizothecium tetrasporum, a fungus from a third family in the order Sordariales, also produces mostly self-fertile dikaryotic spores carrying the two opposite mating types. This was due to a high frequency of second meiotic division segregation at the mating-type locus, indicating the occurrence of a single and systematic crossing-over event between the mating-type locus and the centromere, as in P. anserina. The mating-type locus has the typical Sordariales organization, plus a MAT1-1-1 pseudogene in the MAT1-2 haplotype. High-quality genome assemblies of opposite mating types and segregation analyses revealed a suppression of recombination in a region of 1.47 Mb around the mating-type locus. We detected three evolutionary strata, indicating a stepwise extension of recombination suppression. The three strata displayed no rearrangement or transposable element accumulation but gene losses and gene disruptions were present, and precisely at the strata margins. Our findings indicate a convergent evolution of self-fertile dikaryotic sexual spores across multiple ascomycete fungi. The particular pattern of meiotic segregation at the mating-type locus was associated with recombination suppression around this locus, that had extended stepwise. This association between pseudo-homothallism and recombination suppression across lineages and the presence of gene disruption at the strata limits are consistent with a recently proposed mechanism of sheltering deleterious alleles to explain stepwise recombination suppression.
Collapse
Affiliation(s)
- Nina Vittorelli
- Ecologie Systematique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Gif-sur-Yvette, France
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Cité, Paris, France
- Département de Biologie, École Normale Supérieure, PSL Université Paris, Paris, France
| | | | - Alodie Snirc
- Ecologie Systematique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Gif-sur-Yvette, France
| | - Emilie Levert
- Ecologie Systematique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Gif-sur-Yvette, France
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Cité, Paris, France
| | - Valérie Gautier
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Cité, Paris, France
| | - Christophe Lalanne
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Cité, Paris, France
| | - Elsa De Filippo
- Ecologie Systematique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Gif-sur-Yvette, France
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Cité, Paris, France
| | - Pierre Gladieux
- PHIM Plant Health Institute, Univ Montpellier, INRAE, CIRAD, Institut Agro, IRD, Montpellier, France
| | - Sonia Guillou
- PHIM Plant Health Institute, Univ Montpellier, INRAE, CIRAD, Institut Agro, IRD, Montpellier, France
| | - Yu Zhang
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Sravanthi Tejomurthula
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Igor V. Grigoriev
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, California, United States of America
| | - Robert Debuchy
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Philippe Silar
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Cité, Paris, France
| | - Tatiana Giraud
- Ecologie Systematique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Gif-sur-Yvette, France
| | - Fanny E. Hartmann
- Ecologie Systematique et Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Gif-sur-Yvette, France
- * E-mail:
| |
Collapse
|
27
|
Sex chromosome differentiation via changes in the Y chromosome repeat landscape in African annual killifishes Nothobranchius furzeri and N. kadleci. Chromosome Res 2022; 30:309-333. [PMID: 36208359 DOI: 10.1007/s10577-022-09707-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 09/13/2022] [Accepted: 09/15/2022] [Indexed: 01/25/2023]
Abstract
Homomorphic sex chromosomes and their turnover are common in teleosts. We investigated the evolution of nascent sex chromosomes in several populations of two sister species of African annual killifishes, Nothobranchius furzeri and N. kadleci, focusing on their under-studied repetitive landscape. We combined bioinformatic analyses of the repeatome with molecular cytogenetic techniques, including comparative genomic hybridization, fluorescence in situ hybridization with satellite sequences, ribosomal RNA genes (rDNA) and bacterial artificial chromosomes (BACs), and immunostaining of SYCP3 and MLH1 proteins to mark lateral elements of synaptonemal complexes and recombination sites, respectively. Both species share the same heteromorphic XY sex chromosome system, which thus evolved prior to their divergence. This was corroborated by sequence analysis of a putative master sex determining (MSD) gene gdf6Y in both species. Based on their divergence, differentiation of the XY sex chromosome pair started approximately 2 million years ago. In all populations, the gdf6Y gene mapped within a region rich in satellite DNA on the Y chromosome long arms. Despite their heteromorphism, X and Y chromosomes mostly pair regularly in meiosis, implying synaptic adjustment. In N. kadleci, Y-linked paracentric inversions like those previously reported in N. furzeri were detected. An inversion involving the MSD gene may suppress occasional recombination in the region, which we otherwise evidenced in the N. furzeri population MZCS-121 of the Limpopo clade lacking this inversion. Y chromosome centromeric repeats were reduced compared with the X chromosome and autosomes, which points to a role of relaxed meiotic drive in shaping the Y chromosome repeat landscape. We speculate that the recombination rate between sex chromosomes was reduced due to heterochiasmy. The observed differences between the repeat accumulations on the X and Y chromosomes probably result from high repeat turnover and may not relate closely to the divergence inferred from earlier SNP analyses.
Collapse
|
28
|
He L, Hörandl E. Does polyploidy inhibit sex chromosome evolution in angiosperms? FRONTIERS IN PLANT SCIENCE 2022; 13:976765. [PMID: 36212292 PMCID: PMC9541106 DOI: 10.3389/fpls.2022.976765] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 08/24/2022] [Indexed: 06/16/2023]
Abstract
Dioecy is rare in flowering plants (5-6% of species), but is often controlled genetically by sex-linked regions (SLRs). It has so far been unclear whether, polyploidy affects sex chromosome evolution, as it does in animals, though polyploidy is quite common in angiosperms, including in dioecious species. Plants could be different, as, unlike many animal systems, degenerated sex chromosomes, are uncommon in plants. Here we consider sex determination in plants and plant-specific factors, and propose that constraints created at the origin of polyploids limit successful polyploidization of species with SLRs. We consider the most likely case of a polyploid of a dioecious diploid with an established SLR, and discuss the outcome in autopolyploids and allopolyploids. The most stable system possibly has an SLR on just one chromosome, with a strongly dominant genetic factor in the heterogametic sex (e.g., xxxY male in a tetraploid). If recombination occurs with its homolog, this will prevent Y chromosome degeneration. Polyploidy may also allow for reversibility of multiplied Z or X chromosomes into autosomes. Otherwise, low dosage of Y-linked SLRs compared to their multiple homologous x copies may cause loss of reliable sex-determination at higher ploidy levels. We discuss some questions that can be studied using genome sequencing, chromosome level-assemblies, gene expression studies and analysis of loci under selection.
Collapse
Affiliation(s)
- Li He
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai, China
| | - Elvira Hörandl
- Department of Systematics, Biodiversity and Evolution of Plants, University of Göttingen, Göttingen, Germany
| |
Collapse
|
29
|
Ansai S, Montenegro J, Masengi KWA, Nagano AJ, Yamahira K, Kitano J. Diversity of sex chromosomes in Sulawesian medaka fishes. J Evol Biol 2022; 35:1751-1764. [DOI: 10.1111/jeb.14076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 05/30/2022] [Accepted: 07/14/2022] [Indexed: 12/16/2022]
Affiliation(s)
- Satoshi Ansai
- Graduate School of Life Sciences Tohoku University Sendai Japan
| | - Javier Montenegro
- Tropical Biosphere Research Center University of the Ryukyus Nishihara Japan
| | | | - Atsushi J. Nagano
- Faculty of Agriculture Ryukoku University Otsu Japan
- Institute for Advanced Biosciences Keio University Tsuruoka Japan
| | - Kazunori Yamahira
- Tropical Biosphere Research Center University of the Ryukyus Nishihara Japan
| | - Jun Kitano
- Ecological Genetics Laboratory National Institute of Genetics Shizuoka Japan
| |
Collapse
|
30
|
Elkrewi M, Khauratovich U, Toups MA, Bett VK, Mrnjavac A, Macon A, Fraisse C, Sax L, Huylmans AK, Hontoria F, Vicoso B. ZW sex-chromosome evolution and contagious parthenogenesis in Artemia brine shrimp. Genetics 2022; 222:6670797. [PMID: 35977389 PMCID: PMC9526061 DOI: 10.1093/genetics/iyac123] [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] [Received: 04/15/2022] [Accepted: 07/18/2022] [Indexed: 11/13/2022] Open
Abstract
Eurasian brine shrimp (genus Artemia) have closely related sexual and asexual lineages of parthenogenetic females, which produce rare males at low frequencies. Although they are known to have ZW chromosomes, these are not well characterized, and it is unclear whether they are shared across the clade. Furthermore, the underlying genetic architecture of the transmission of asexuality, which can occur when rare males mate with closely related sexual females, is not well understood. We produced a chromosome-level assembly for the sexual Eurasian species A. sinica and characterized in detail the pair of sex chromosomes of this species. We combined this new assembly with short-read genomic data for the sexual species A. sp. Kazakhstan and several asexual lineages of A. parthenogenetica, allowing us to perform an in-depth characterization of sex-chromosome evolution across the genus. We identified a small differentiated region of the ZW pair that is shared by all sexual and asexual lineages, supporting the shared ancestry of the sex chromosomes. We also inferred that recombination suppression has spread to larger sections of the chromosome independently in the American and Eurasian lineages. Finally, we took advantage of a rare male, which we backcrossed to sexual females, to explore the genetic basis of asexuality. Our results suggest that parthenogenesis is likely partly controlled by a locus on the Z chromosome, highlighting the interplay between sex determination and asexuality.
Collapse
Affiliation(s)
- Marwan Elkrewi
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria
| | - Uladzislava Khauratovich
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria.,Department of Chromosome Biology, Max Perutz Labs, University of Vienna, 1030, Austria
| | - Melissa A Toups
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria.,Department of Life and Environmental Sciences, Faculty of Science and Technology, Bournemouth University, BH12 5BB, UK
| | | | - Andrea Mrnjavac
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria
| | - Ariana Macon
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria
| | - Christelle Fraisse
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria.,CNRS, Univ. Lille, UMR 8198-Evo-Eco-Paleo, F-59000 Lille, France
| | - Luca Sax
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria.,Lewis and Clark College, Portland, OR 97219, USA
| | - Ann Kathrin Huylmans
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria.,Institute of Organismic and Molecular Evolution, Johannes Guttenberg Universität Mainz, Mainz, 55122, Germany
| | - Francisco Hontoria
- Instituto de Acuicultura de Torre de la Sal (IATS-CSIC), Ribera de Cabanes, 12595, Spain
| | - Beatriz Vicoso
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria
| |
Collapse
|
31
|
Hearn KE, Koch EL, Stankowski S, Butlin RK, Faria R, Johannesson K, Westram AM. Differing associations between sex determination and sex‐linked inversions in two ecotypes of
Littorina saxatilis. Evol Lett 2022; 6:358-374. [PMID: 36254259 PMCID: PMC9554762 DOI: 10.1002/evl3.295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 07/07/2022] [Accepted: 07/20/2022] [Indexed: 12/14/2022] Open
Abstract
Sexual antagonism is a common hypothesis for driving the evolution of sex chromosomes, whereby recombination suppression is favored between sexually antagonistic loci and the sex‐determining locus to maintain beneficial combinations of alleles. This results in the formation of a sex‐determining region. Chromosomal inversions may contribute to recombination suppression but their precise role in sex chromosome evolution remains unclear. Because local adaptation is frequently facilitated through the suppression of recombination between adaptive loci by chromosomal inversions, there is potential for inversions that cover sex‐determining regions to be involved in local adaptation as well, particularly if habitat variation creates environment‐dependent sexual antagonism. With these processes in mind, we investigated sex determination in a well‐studied example of local adaptation within a species: the intertidal snail, Littorina saxatilis. Using SNP data from a Swedish hybrid zone, we find novel evidence for a female‐heterogametic sex determination system that is restricted to one ecotype. Our results suggest that four putative chromosomal inversions, two previously described and two newly discovered, span the putative sex chromosome pair. We determine their differing associations with sex, which suggest distinct strata of differing ages. The same inversions are found in the second ecotype but do not show any sex association. The striking disparity in inversion‐sex associations between ecotypes that are connected by gene flow across a habitat transition that is just a few meters wide indicates a difference in selective regime that has produced a distinct barrier to the spread of the newly discovered sex‐determining region between ecotypes. Such sex chromosome‐environment interactions have not previously been uncovered in L. saxatilis and are known in few other organisms. A combination of both sex‐specific selection and divergent natural selection is required to explain these highly unusual patterns.
Collapse
Affiliation(s)
- Katherine E. Hearn
- Ecology and Evolutionary Biology, School of Biosciences University of Sheffield Sheffield S10 2TN United Kingdom
| | - Eva L. Koch
- Ecology and Evolutionary Biology, School of Biosciences University of Sheffield Sheffield S10 2TN United Kingdom
- Department of Zoology University of Cambridge Cambridge CB2 3EJ United Kingdom
| | - Sean Stankowski
- Ecology and Evolutionary Biology, School of Biosciences University of Sheffield Sheffield S10 2TN United Kingdom
- ISTA (Institute of Science and Technology Austria) Klosterneuburg 3400 Austria
| | - Roger K. Butlin
- Ecology and Evolutionary Biology, School of Biosciences University of Sheffield Sheffield S10 2TN United Kingdom
- Department of Marine Sciences University of Gothenburg Strömstad SE‐45296 Sweden
| | - Rui Faria
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado Campus de Vairão, Universidade do Porto Vairão 4485‐661 Portugal
- BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO Campus de Vairão, Universidade do Porto Vairão 4485‐661 Portugal
| | - Kerstin Johannesson
- Department of Marine Sciences University of Gothenburg Strömstad SE‐45296 Sweden
| | - Anja M. Westram
- ISTA (Institute of Science and Technology Austria) Klosterneuburg 3400 Austria
- Faculty of Biosciences and Aquaculture Nord University Bodø 8026 Norway
| |
Collapse
|
32
|
Meisel RP. Ecology and the evolution of sex chromosomes. J Evol Biol 2022; 35:1601-1618. [PMID: 35950939 DOI: 10.1111/jeb.14074] [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: 12/17/2021] [Revised: 07/15/2022] [Accepted: 07/21/2022] [Indexed: 11/29/2022]
Abstract
Sex chromosomes are common features of animal genomes, often carrying a sex determination gene responsible for initiating the development of sexually dimorphic traits. The specific chromosome that serves as the sex chromosome differs across taxa as a result of fusions between sex chromosomes and autosomes, along with sex chromosome turnover-autosomes becoming sex chromosomes and sex chromosomes 'reverting' back to autosomes. In addition, the types of genes on sex chromosomes frequently differ from the autosomes, and genes on sex chromosomes often evolve faster than autosomal genes. Sex-specific selection pressures, such as sexual antagonism and sexual selection, are hypothesized to be responsible for sex chromosome turnovers, the unique gene content of sex chromosomes and the accelerated evolutionary rates of genes on sex chromosomes. Sex-specific selection has pronounced effects on sex chromosomes because their sex-biased inheritance can tilt the balance of selection in favour of one sex. Despite the general consensus that sex-specific selection affects sex chromosome evolution, most population genetic models are agnostic as to the specific sources of these sex-specific selection pressures, and many of the details about the effects of sex-specific selection remain unresolved. Here, I review the evidence that ecological factors, including variable selection across heterogeneous environments and conflicts between sexual and natural selection, can be important determinants of sex-specific selection pressures that shape sex chromosome evolution. I also explain how studying the ecology of sex chromosome evolution can help us understand important and unresolved aspects of both sex chromosome evolution and sex-specific selection.
Collapse
Affiliation(s)
- Richard P Meisel
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
| |
Collapse
|
33
|
Dufresnes C, Crochet PA. Sex chromosomes as supergenes of speciation: why amphibians defy the rules? Philos Trans R Soc Lond B Biol Sci 2022; 377:20210202. [PMID: 35694748 PMCID: PMC9189495 DOI: 10.1098/rstb.2021.0202] [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] [Indexed: 12/14/2022] Open
Abstract
As reflected by the two rules of speciation (Haldane's rule and the large X-/Z-effect), sex chromosomes are expected to behave like supergenes of speciation: they recombine only in one sex (XX females or ZZ males), supposedly recruit sexually antagonistic genes and evolve faster than autosomes, which can all contribute to pre-zygotic and post-zygotic isolation. While this has been mainly studied in organisms with conserved sex-determining systems and highly differentiated (heteromorphic) sex chromosomes like mammals, birds and some insects, these expectations are less clear in organismal groups where sex chromosomes repeatedly change and remain mostly homomorphic, like amphibians. In this article, we review the proposed roles of sex-linked genes in isolating nascent lineages throughout the speciation continuum and discuss their support in amphibians given current knowledge of sex chromosome evolution and speciation modes. Given their frequent recombination and lack of differentiation, we argue that amphibian sex chromosomes are not expected to become supergenes of speciation, which is reflected by the rarity of empirical studies consistent with a 'large sex chromosome effect' in frogs and toads. The diversity of sex chromosome systems in amphibians has a high potential to disentangle the evolutionary mechanisms responsible for the emergence of sex-linked speciation genes in other organisms. This article is part of the theme issue 'Genomic architecture of supergenes: causes and evolutionary consequences'.
Collapse
Affiliation(s)
- Christophe Dufresnes
- LASER, College of Biology and Environment, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | | |
Collapse
|
34
|
Montiel EE, Badenhorst D, Lee L, Valenzuela N. Evolution and dosage compensation of nucleolar organizing regions (NORs) mediated by mobile elements in turtles with female (ZZ/ZW) but not with male (XX/XY) heterogamety. J Evol Biol 2022; 35:1709-1720. [PMID: 35877473 PMCID: PMC10087745 DOI: 10.1111/jeb.14064] [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: 02/14/2022] [Revised: 04/26/2022] [Accepted: 06/28/2022] [Indexed: 11/28/2022]
Abstract
Understanding the evolution and regulation of nucleolar organizing regions (NORs) is important to elucidate genome structure and function. This is because ribosomal gene (rDNA) copy number and activity mediate protein biosynthesis, stress response, ageing, disease, dosage compensation and genome stability. Here, we found contrasting dosage compensation of sex-linked NORs in turtles with male and female heterogamety. Most taxa examined exhibit homomorphic rRNA gene clusters in a single autosome pair (determined by 28S rDNA fluorescence in situ hybridization), whereas NORs are sex-linked in Apalone spinifera, Pelodiscus sinensis and Staurotypus triporcatus. Full-dosage compensation upregulates the male X-NOR (determined via silver staining-AgNOR) in Staurotypus (who lacks Y-NOR) compared with female X-AgNORs. In softshell Apalone and Pelodiscus, who share homologous ZZ/ZW micro-chromosomes, their enlarged W-NOR is partially active (due to 28S rDNA invasion by R2 retroelements), whereas their smaller Z-NOR is silent in females but active in both male-Zs (presumably because the W-NOR meets cellular demands and excessive NOR activity is costly). We hypothesize that R2 disruption favoured W enlargement to add intact 28S-units, perhaps facilitated by reduced recombination during sex chromosome evolution. The molecular basis of the potentially adaptive female Z-silencing is likely intricate and perhaps epigenetic, as non-ribosomal Z genes are active in Apalone females. Yet, Emydura maquarii exhibit identical heteromorphism in their autosomal NOR (R2 invaded 28S-units and the small-autosome NOR is silent), suggesting that the softshell turtle pattern can evolve independent of sex chromosome evolution. Our study illuminates the complex sex chromosome evolution and dosage compensation of non-model systems that challenges classic paradigms.
Collapse
Affiliation(s)
- Eugenia E Montiel
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, Iowa, USA.,Department of Experimental Biology (Genetics Area), University of Jaén, Jaén, Spain
| | - Daleen Badenhorst
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, Iowa, USA
| | - LingSze Lee
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, Iowa, USA
| | - Nicole Valenzuela
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, Iowa, USA
| |
Collapse
|
35
|
Käfer J. How sex chromosomes get trapped into nonrecombination. PLoS Biol 2022; 20:e3001718. [PMID: 35882230 PMCID: PMC9295974 DOI: 10.1371/journal.pbio.3001718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
We know that suppression of recombination leads to degeneration of Y chromosomes, but it has remained difficult to understand how features with such strong negative effects actually arise. This Primer explores a new model published in PLOS Biology that reveals how this could happen.
Collapse
Affiliation(s)
- Jos Käfer
- Université de Lyon, Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Villeurbanne, France
- Université de Montpellier, IRD, CIRAD, UMR Diversité Adaptation et Développement des plantes, Montpellier, France
- * E-mail:
| |
Collapse
|
36
|
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.
Collapse
|
37
|
Jay P, Tezenas E, Véber A, Giraud T. Sheltering of deleterious mutations explains the stepwise extension of recombination suppression on sex chromosomes and other supergenes. PLoS Biol 2022; 20:e3001698. [PMID: 35853091 PMCID: PMC9295944 DOI: 10.1371/journal.pbio.3001698] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 06/03/2022] [Indexed: 12/19/2022] Open
Abstract
Many organisms have sex chromosomes with large nonrecombining regions that have expanded stepwise, generating "evolutionary strata" of differentiation. The reasons for this remain poorly understood, but the principal hypotheses proposed to date are based on antagonistic selection due to differences between sexes. However, it has proved difficult to obtain empirical evidence of a role for sexually antagonistic selection in extending recombination suppression, and antagonistic selection has been shown to be unlikely to account for the evolutionary strata observed on fungal mating-type chromosomes. We show here, by mathematical modeling and stochastic simulation, that recombination suppression on sex chromosomes and around supergenes can expand under a wide range of parameter values simply because it shelters recessive deleterious mutations, which are ubiquitous in genomes. Permanently heterozygous alleles, such as the male-determining allele in XY systems, protect linked chromosomal inversions against the expression of their recessive mutation load, leading to the successive accumulation of inversions around these alleles without antagonistic selection. Similar results were obtained with models assuming recombination-suppressing mechanisms other than chromosomal inversions and for supergenes other than sex chromosomes, including those without XY-like asymmetry, such as fungal mating-type chromosomes. However, inversions capturing a permanently heterozygous allele were found to be less likely to spread when the mutation load segregating in populations was lower (e.g., under large effective population sizes or low mutation rates). This may explain why sex chromosomes remain homomorphic in some organisms but are highly divergent in others. Here, we model a simple and testable hypothesis explaining the stepwise extensions of recombination suppression on sex chromosomes, mating-type chromosomes, and supergenes in general.
Collapse
Affiliation(s)
- Paul Jay
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique et Evolution, 91190, Gif-sur-Yvette, France
- * E-mail:
| | - Emilie Tezenas
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique et Evolution, 91190, Gif-sur-Yvette, France
- Univ. Lille, CNRS, UMR 8198 –Evo-Eco-Paleo, F-59000 Lille, France
- Université Paris Cité, CNRS, MAP 5, F-75006 Paris, France
| | - Amandine Véber
- Université Paris Cité, CNRS, MAP 5, F-75006 Paris, France
| | - Tatiana Giraud
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique et Evolution, 91190, Gif-sur-Yvette, France
| |
Collapse
|
38
|
Keating SE, Greenbaum E, Johnson JD, Gamble T. Identification of a cis-sex chromosome transition in banded geckos (Coleonyx, Eublepharidae, Gekkota). J Evol Biol 2022; 35:1675-1682. [PMID: 35665979 DOI: 10.1111/jeb.14022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 04/13/2022] [Accepted: 04/28/2022] [Indexed: 12/24/2022]
Abstract
Sex-determination systems are highly variable amongst vertebrate groups, and the prevalence of genomic data has greatly expanded our knowledge of how diverse some groups truly are. Gecko lizards are known to possess a variety of sex-determination systems, and each new study increases our knowledge of this diversity. Here, we used RADseq to identify male-specific markers in the banded gecko Coleonyx brevis, indicating this species has a XX/XY sex-determination system. Furthermore, we show that these sex-linked regions are not homologous to the XX/XY sex chromosomes of two related Coleonyx species, C. elegans and C. mitratus, suggesting that a cis-sex chromosome turnover-a change in sex chromosomes without a concomitant change in heterogamety-has occurred within the genus. These findings demonstrate the utility of genome-scale data to uncover novel sex chromosomes and further highlight the diversity of gecko sex chromosomes.
Collapse
Affiliation(s)
- Shannon E Keating
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, USA
| | - Eli Greenbaum
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas, USA
| | - Jerry D Johnson
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas, USA
| | - Tony Gamble
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, USA.,Milwaukee Public Museum, Milwaukee, Wisconsin, USA.,Bell Museum of Natural History, University of Minnesota, St. Paul, Minnesota, USA
| |
Collapse
|
39
|
Olito C, Ponnikas S, Hansson B, Abbott JK. Consequences of partially recessive deleterious genetic variation for the evolution of inversions suppressing recombination between sex chromosomes. Evolution 2022; 76:1320-1330. [PMID: 35482933 PMCID: PMC9324078 DOI: 10.1111/evo.14496] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 03/15/2022] [Indexed: 01/21/2023]
Abstract
The evolution of suppressed recombination between sex chromosomes is widely hypothesized to be driven by sexually antagonistic selection (SA), where tighter linkage between the sex-determining gene(s) and nearby SA loci is favored when it couples male-beneficial alleles to the proto-Y chromosome, and female-beneficial alleles to the proto-X. Despite limited empirical evidence, the SA selection hypothesis overshadows several alternatives, including an incomplete but often-repeated "sheltering hypothesis" that suggests that expansion of the sex-linked region (SLR) reduces homozygous expression of partially recessive deleterious mutations at selected loci. Here, we use population genetic models to evaluate the consequences of deleterious mutational variation for the evolution of neutral chromosomal inversions expanding the SLR on proto-Y chromosomes. We find that SLR-expanding inversions face a race against time: lightly loaded inversions are initially beneficial, but eventually become deleterious as they accumulate new mutations, and must fix before this window of opportunity closes. The outcome of this race is strongly influenced by inversion size, the mutation rate, and the dominance coefficient of deleterious mutations. Yet, small inversions have elevated fixation probabilities relative to neutral expectations for biologically plausible parameter values. Our results demonstrate that deleterious genetic variation can plausibly drive recombination suppression in small steps and would be most consistent with empirical patterns of small evolutionary strata or gradual recombination arrest.
Collapse
Affiliation(s)
- Colin Olito
- Department of BiologyLund UniversityLund22362Sweden
| | - Suvi Ponnikas
- Department of BiologyLund UniversityLund22362Sweden
- Current address: Ecology and Genetics Research UnitUniversity of OuluOulu90014Finland
| | | | | |
Collapse
|
40
|
Muyle A, Marais GAB, Bačovský V, Hobza R, Lenormand T. Dosage compensation evolution in plants: theories, controversies and mechanisms. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210222. [PMID: 35306896 PMCID: PMC8935305 DOI: 10.1098/rstb.2021.0222] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In a minority of flowering plants, separate sexes are genetically determined by sex chromosomes. The Y chromosome has a non-recombining region that degenerates, causing a reduced expression of Y genes. In some species, the lower Y expression is accompanied by dosage compensation (DC), a mechanism that re-equalizes male and female expression and/or brings XY male expression back to its ancestral level. Here, we review work on DC in plants, which started as early as the late 1960s with cytological approaches. The use of transcriptomics fired a controversy as to whether DC existed in plants. Further work revealed that various plants exhibit partial DC, including a few species with young and homomorphic sex chromosomes. We are starting to understand the mechanisms responsible for DC in some plants, but in most species, we lack the data to differentiate between global and gene-by-gene DC. Also, it is unknown why some species evolve many dosage compensated genes while others do not. Finally, the forces that drive DC evolution remain mysterious, both in plants and animals. We review the multiple evolutionary theories that have been proposed to explain DC patterns in eukaryotes with XY or ZW sex chromosomes. This article is part of the theme issue 'Sex determination and sex chromosome evolution in land plants'.
Collapse
Affiliation(s)
- Aline Muyle
- Laboratoire 'Biométrie et Biologie Evolutive', CNRS/Université Lyon 1, Lyon, France
| | - Gabriel A B Marais
- Laboratoire 'Biométrie et Biologie Evolutive', CNRS/Université Lyon 1, Lyon, France.,CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4099-002 Porto, Portugal.,BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal
| | - Václav Bačovský
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, Brno, Czech Republic
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, Brno, Czech Republic
| | - Thomas Lenormand
- CEFE, University of Montpellier, CNRS, EPHE, IRD, Montpellier, France
| |
Collapse
|
41
|
Renner SS, Müller NA. Sex determination and sex chromosome evolution in land plants. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210210. [PMID: 35306895 PMCID: PMC8935313 DOI: 10.1098/rstb.2021.0210] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 01/19/2022] [Indexed: 01/02/2023] Open
Abstract
Linnaeus's very first opus, written when he was 22 years old, dealt with the analogy that exists between plants and animals in how they 'propagate their species', and a revised version with a plate depicting the union of male and female Mercurialis annua plants became a foundational text on the sexuality of plants. The question how systems with separate males and females have evolved in sedentary organisms that appear ancestrally bisexual has fascinated biologists ever since. The phenomenon, termed dioecy, has important consequences for plant reproductive success and is of commercial interest since it affects seed quality and fruit production. This theme issue presents a series of articles that synthesize and challenge the current understanding of how plants achieve dioecy. The articles deal with a broad set of taxa, including Coccinia, Ginkgo, Mercurialis, Populus, Rumex and Silene, as well as overarching topics, such as the field's terminology, analogies with animal sex determination systems, evolutionary pathways to dioecy, dosage compensation, and the longevity of the two sexes. In this introduction, we focus on four topics, each addressed by several articles from different angles and with different conclusions. Our highlighting of unclear or controversial issues may help future studies to build on the current understanding and to ask new questions that will expand our knowledge of plant sexual systems. This article is part of the theme issue 'Sex determination and sex chromosome evolution in land plants'.
Collapse
Affiliation(s)
- Susanne S. Renner
- Department of Biology, Washington University, Saint Louis, MO 63130, USA
| | - Niels A. Müller
- Thünen-Institute of Forest Genetics, Sieker Landstrasse 2, 22927 Grosshansdorf, Germany
| |
Collapse
|
42
|
The evolution of gene regulation on sex chromosomes. Trends Genet 2022; 38:844-855. [DOI: 10.1016/j.tig.2022.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 04/07/2022] [Accepted: 04/11/2022] [Indexed: 11/20/2022]
|
43
|
Muralidhar P, Veller C. A new model of sex chromosome evolution. Science 2022; 375:616-617. [PMID: 35143294 DOI: 10.1126/science.abn7410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A new model, based on the evolution of gene regulation, challenges the classical theory.
Collapse
Affiliation(s)
- Pavitra Muralidhar
- Center for Population Biology, University of California, Davis, CA, USA.,Department of Evolution and Ecology, University of California, Davis, CA, USA
| | - Carl Veller
- Center for Population Biology, University of California, Davis, CA, USA.,Department of Evolution and Ecology, University of California, Davis, CA, USA
| |
Collapse
|