1
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Moore T. X centromeric drive may explain the prevalence of polycystic ovary syndrome and other conditions: Genomic structure of the human X chromosome pericentromeric region is consistent with meiotic drive associated with PCOS and other conditions. Bioessays 2024; 46:e2400056. [PMID: 39072829 DOI: 10.1002/bies.202400056] [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: 03/12/2024] [Revised: 07/02/2024] [Accepted: 07/04/2024] [Indexed: 07/30/2024]
Abstract
X chromosome centromeric drive may explain the prevalence of polycystic ovary syndrome and contribute to oocyte aneuploidy, menopause, and other conditions. The mammalian X chromosome may be vulnerable to meiotic drive because of X inactivation in the female germline. The human X pericentromeric region contains genes potentially involved in meiotic mechanisms, including multiple SPIN1 and ZXDC paralogs. This is consistent with a multigenic drive system comprising differential modification of the active and inactive X chromosome centromeres in female primordial germ cells and preferential segregation of the previously inactivated X chromosome centromere to the polar body at meiosis I. The drive mechanism may explain differences in X chromosome regulation in the female germlines of the human and mouse and, based on the functions encoded by the genes in the region, the transmission of X pericentromeric genetic or epigenetic variants to progeny could contribute to preeclampsia, autism, and differences in sexual differentiation.
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Affiliation(s)
- Tom Moore
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
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2
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Li X, Mank JE, Ban L. The grasshopper genome reveals long-term gene content conservation of the X Chromosome and temporal variation in X Chromosome evolution. Genome Res 2024; 34:997-1007. [PMID: 39103228 PMCID: PMC11368200 DOI: 10.1101/gr.278794.123] [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: 11/30/2023] [Accepted: 07/02/2024] [Indexed: 08/07/2024]
Abstract
We present the first chromosome-level genome assembly of the grasshopper, Locusta migratoria, one of the largest insect genomes. We use coverage differences between females (XX) and males (X0) to identify the X Chromosome gene content, and find that the X Chromosome shows both complete dosage compensation in somatic tissues and an underrepresentation of testis-expressed genes. X-linked gene content from L. migratoria is highly conserved across seven insect orders, namely Orthoptera, Odonata, Phasmatodea, Hemiptera, Neuroptera, Coleoptera, and Diptera, and the 800 Mb grasshopper X Chromosome is homologous to the fly ancestral X Chromosome despite 400 million years of divergence, suggesting either repeated origin of sex chromosomes with highly similar gene content, or long-term conservation of the X Chromosome. We use this broad conservation of the X Chromosome to test for temporal dynamics to Fast-X evolution, and find evidence of a recent burst evolution for new X-linked genes in contrast to slow evolution of X-conserved genes.
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Affiliation(s)
- Xinghua Li
- Department of Grassland Resources and Ecology, College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China
- National Engineering Laboratory for Animal Breeding, Department of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Judith E Mank
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - Liping Ban
- Department of Grassland Resources and Ecology, College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China;
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3
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Cecalev D, Viçoso B, Galupa R. Compensation of gene dosage on the mammalian X. Development 2024; 151:dev202891. [PMID: 39140247 PMCID: PMC11361640 DOI: 10.1242/dev.202891] [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] [Indexed: 08/15/2024]
Abstract
Changes in gene dosage can have tremendous evolutionary potential (e.g. whole-genome duplications), but without compensatory mechanisms, they can also lead to gene dysregulation and pathologies. Sex chromosomes are a paradigmatic example of naturally occurring gene dosage differences and their compensation. In species with chromosome-based sex determination, individuals within the same population necessarily show 'natural' differences in gene dosage for the sex chromosomes. In this Review, we focus on the mammalian X chromosome and discuss recent new insights into the dosage-compensation mechanisms that evolved along with the emergence of sex chromosomes, namely X-inactivation and X-upregulation. We also discuss the evolution of the genetic loci and molecular players involved, as well as the regulatory diversity and potentially different requirements for dosage compensation across mammalian species.
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Affiliation(s)
- Daniela Cecalev
- Molecular, Cellular and Developmental Biology (MCD) Unit, Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062, Toulouse, France
| | - Beatriz Viçoso
- Institute of Science and Technology Austria (ISTA), Am Campus 1, Klosterneuburg 3400, Austria
| | - Rafael Galupa
- Molecular, Cellular and Developmental Biology (MCD) Unit, Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062, Toulouse, France
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4
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Murphy WJ, Harris AJ. Toward telomere-to-telomere cat genomes for precision medicine and conservation biology. Genome Res 2024; 34:655-664. [PMID: 38849156 PMCID: PMC11216403 DOI: 10.1101/gr.278546.123] [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] [Indexed: 06/09/2024]
Abstract
Genomic data from species of the cat family Felidae promise to stimulate veterinary and human medical advances, and clarify the coherence of genome organization. We describe how interspecies hybrids have been instrumental in the genetic analysis of cats, from the first genetic maps to propelling cat genomes toward the T2T standard set by the human genome project. Genotype-to-phenotype mapping in cat models has revealed dozens of health-related genetic variants, the molecular basis for mammalian pigmentation and patterning, and species-specific adaptations. Improved genomic surveillance of natural and captive populations across the cat family tree will increase our understanding of the genetic architecture of traits, population dynamics, and guide a future of genome-enabled biodiversity conservation.
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Affiliation(s)
- William J Murphy
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458, USA;
- Department of Biology, Texas A&M University, College Station, Texas 77843-4458, USA
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, Texas 77843-4458, USA
| | - Andrew J Harris
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458, USA
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, Texas 77843-4458, USA
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5
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Lasne C, Elkrewi M, Toups MA, Layana L, Macon A, Vicoso B. The Scorpionfly (Panorpa cognata) Genome Highlights Conserved and Derived Features of the Peculiar Dipteran X Chromosome. Mol Biol Evol 2023; 40:msad245. [PMID: 37988296 PMCID: PMC10715201 DOI: 10.1093/molbev/msad245] [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: 07/10/2023] [Revised: 10/05/2023] [Accepted: 11/07/2023] [Indexed: 11/23/2023] Open
Abstract
Many insects carry an ancient X chromosome-the Drosophila Muller element F-that likely predates their origin. Interestingly, the X has undergone turnover in multiple fly species (Diptera) after being conserved for more than 450 My. The long evolutionary distance between Diptera and other sequenced insect clades makes it difficult to infer what could have contributed to this sudden increase in rate of turnover. Here, we produce the first genome and transcriptome of a long overlooked sister-order to Diptera: Mecoptera. We compare the scorpionfly Panorpa cognata X-chromosome gene content, expression, and structure to that of several dipteran species as well as more distantly related insect orders (Orthoptera and Blattodea). We find high conservation of gene content between the mecopteran X and the dipteran Muller F element, as well as several shared biological features, such as the presence of dosage compensation and a low amount of genetic diversity, consistent with a low recombination rate. However, the 2 homologous X chromosomes differ strikingly in their size and number of genes they carry. Our results therefore support a common ancestry of the mecopteran and ancestral dipteran X chromosomes, and suggest that Muller element F shrank in size and gene content after the split of Diptera and Mecoptera, which may have contributed to its turnover in dipteran insects.
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Affiliation(s)
- Clementine Lasne
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Marwan Elkrewi
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Melissa A Toups
- Department of Life and Environmental Sciences, Bournemouth University, Poole, UK
| | - Lorena Layana
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Ariana Macon
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Beatriz Vicoso
- Institute of Science and Technology Austria, Klosterneuburg, Austria
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6
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Roy SW. Did the creeping vole sex chromosomes evolve through a cascade of adaptive responses to a selfish x chromosome? Bioessays 2023; 45:e2100164. [PMID: 37941456 DOI: 10.1002/bies.202100164] [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: 10/27/2021] [Revised: 10/07/2023] [Accepted: 10/10/2023] [Indexed: 11/10/2023]
Abstract
The creeping vole Microtus oregoni exhibits remarkably transformed sex chromosome biology, with complete chromosome drive/drag, X-Y fusions, sex reversed X complements, biased X inactivation, and X chromosome degradation. Beginning with a selfish X chromosome, I propose a series of adaptations leading to this system, each compensating for deleterious consequences of the preceding adaptation: (1) YY embryonic inviability favored evolution of a selfish feminizing X chromosome; (2) the consequent Y chromosome transmission disadvantage favored X-Y fusion ("XP "); (3) Xist-based silencing of Y-derived XP genes favored a second X-Y fusion ("XM "); (4) X chromosome dosage-related costs in XP XM males favored the evolution of XM loss during spermatogenesis; (5) X chromosomal dosage-related costs in XM 0 females favored the evolution of XM drive during oogenesis; and (6) degradation of the non-recombining XP favored the evolution of biased X chromosome inactivation. I discuss recurrent rodent sex chromosome transformation, and selfish genes as a constructive force in evolution.
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7
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Jevit MJ, Castaneda C, Paria N, Das PJ, Miller D, Antczak DF, Kalbfleisch TS, Davis BW, Raudsepp T. Trio-binning of a hinny refines the comparative organization of the horse and donkey X chromosomes and reveals novel species-specific features. Sci Rep 2023; 13:20180. [PMID: 37978222 PMCID: PMC10656420 DOI: 10.1038/s41598-023-47583-x] [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: 07/24/2023] [Accepted: 11/14/2023] [Indexed: 11/19/2023] Open
Abstract
We generated single haplotype assemblies from a hinny hybrid which significantly improved the gapless contiguity for horse and donkey autosomal genomes and the X chromosomes. We added over 15 Mb of missing sequence to both X chromosomes, 60 Mb to donkey autosomes and corrected numerous errors in donkey and some in horse reference genomes. We resolved functionally important X-linked repeats: the DXZ4 macrosatellite and ampliconic Equine Testis Specific Transcript Y7 (ETSTY7). We pinpointed the location of the pseudoautosomal boundaries (PAB) and determined the size of the horse (1.8 Mb) and donkey (1.88 Mb) pseudoautosomal regions (PARs). We discovered distinct differences in horse and donkey PABs: a testis-expressed gene, XKR3Y, spans horse PAB with exons1-2 located in Y and exon3 in the X-Y PAR, whereas the donkey XKR3Y is Y-specific. DXZ4 had a similar ~ 8 kb monomer in both species with 10 copies in horse and 20 in donkey. We assigned hundreds of copies of ETSTY7, a sequence horizontally transferred from Parascaris and massively amplified in equids, to horse and donkey X chromosomes and three autosomes. The findings and products contribute to molecular studies of equid biology and advance research on X-linked conditions, sex chromosome regulation and evolution in equids.
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Affiliation(s)
- Matthew J Jevit
- School of Veterinary Medicine, Texas A&M University, College Station, TX, 77843, USA
| | - Caitlin Castaneda
- School of Veterinary Medicine, Texas A&M University, College Station, TX, 77843, USA
| | - Nandina Paria
- Texas Scottish Rite Hospital for Children, Dallas, TX, 75219, USA
| | - Pranab J Das
- ICAR-National Research Centre on Pig, Rani, Guwahati, Assam, 781131, India
| | - Donald Miller
- Baker Institute for Animal Health, Cornell University, Ithaca, NY, 14853, USA
| | - Douglas F Antczak
- Baker Institute for Animal Health, Cornell University, Ithaca, NY, 14853, USA
| | - Theodore S Kalbfleisch
- Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, KY, 40546, USA
| | - Brian W Davis
- School of Veterinary Medicine, Texas A&M University, College Station, TX, 77843, USA.
| | - Terje Raudsepp
- School of Veterinary Medicine, Texas A&M University, College Station, TX, 77843, USA.
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8
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Bredemeyer KR, Hillier L, Harris AJ, Hughes GM, Foley NM, Lawless C, Carroll RA, Storer JM, Batzer MA, Rice ES, Davis BW, Raudsepp T, O'Brien SJ, Lyons LA, Warren WC, Murphy WJ. Single-haplotype comparative genomics provides insights into lineage-specific structural variation during cat evolution. Nat Genet 2023; 55:1953-1963. [PMID: 37919451 PMCID: PMC10845050 DOI: 10.1038/s41588-023-01548-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 09/20/2023] [Indexed: 11/04/2023]
Abstract
The role of structurally dynamic genomic regions in speciation is poorly understood due to challenges inherent in diploid genome assembly. Here we reconstructed the evolutionary dynamics of structural variation in five cat species by phasing the genomes of three interspecies F1 hybrids to generate near-gapless single-haplotype assemblies. We discerned that cat genomes have a paucity of segmental duplications relative to great apes, explaining their remarkable karyotypic stability. X chromosomes were hotspots of structural variation, including enrichment with inversions in a large recombination desert with characteristics of a supergene. The X-linked macrosatellite DXZ4 evolves more rapidly than 99.5% of the genome clarifying its role in felid hybrid incompatibility. Resolved sensory gene repertoires revealed functional copy number changes associated with ecomorphological adaptations, sociality and domestication. This study highlights the value of gapless genomes to reveal structural mechanisms underpinning karyotypic evolution, reproductive isolation and ecological niche adaptation.
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Affiliation(s)
- Kevin R Bredemeyer
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
- Interdisciplinary Program in Genetics & Genomics, Texas A&M University, College Station, TX, USA
| | - LaDeana Hillier
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Andrew J Harris
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
- Interdisciplinary Program in Genetics & Genomics, Texas A&M University, College Station, TX, USA
| | - Graham M Hughes
- School of Biology & Environmental Sciences, University College Dublin, Dublin, Ireland
| | - Nicole M Foley
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Colleen Lawless
- School of Biology & Environmental Sciences, University College Dublin, Dublin, Ireland
| | - Rachel A Carroll
- Department of Animal Sciences, University of Missouri, Columbia, MO, USA
| | | | - Mark A Batzer
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Edward S Rice
- Department of Animal Sciences, University of Missouri, Columbia, MO, USA
| | - Brian W Davis
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
- Interdisciplinary Program in Genetics & Genomics, Texas A&M University, College Station, TX, USA
| | - Terje Raudsepp
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
- Interdisciplinary Program in Genetics & Genomics, Texas A&M University, College Station, TX, USA
| | - Stephen J O'Brien
- Guy Harvey Oceanographic Center, Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Leslie A Lyons
- Department of Veterinary Medicine & Surgery, University of Missouri, Columbia, MO, USA
| | - Wesley C Warren
- Department of Animal Sciences, University of Missouri, Columbia, MO, USA.
| | - William J Murphy
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA.
- Interdisciplinary Program in Genetics & Genomics, Texas A&M University, College Station, TX, USA.
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9
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Flack N, Drown M, Walls C, Pratte J, McLain A, Faulk C. Chromosome-level, nanopore-only genome and allele-specific DNA methylation of Pallas's cat, Otocolobus manul. NAR Genom Bioinform 2023; 5:lqad033. [PMID: 37025970 PMCID: PMC10071556 DOI: 10.1093/nargab/lqad033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 02/10/2023] [Accepted: 03/17/2023] [Indexed: 04/07/2023] Open
Abstract
Pallas's cat, or the manul cat (Otocolobus manul), is a small felid native to the grasslands and steppes of central Asia. Population strongholds in Mongolia and China face growing challenges from climate change, habitat fragmentation, poaching, and other sources. These threats, combined with O. manul's zoo collection popularity and value in evolutionary biology, necessitate improvement of species genomic resources. We used standalone nanopore sequencing to assemble a 2.5 Gb, 61-contig nuclear assembly and 17097 bp mitogenome for O. manul. The primary nuclear assembly had 56× sequencing coverage, a contig N50 of 118 Mb, and a 94.7% BUSCO completeness score for Carnivora-specific genes. High genome collinearity within Felidae permitted alignment-based scaffolding onto the fishing cat (Prionailurus viverrinus) reference genome. Manul contigs spanned all 19 felid chromosomes with an inferred total gap length of less than 400 kilobases. Modified basecalling and variant phasing produced an alternate pseudohaplotype assembly and allele-specific DNA methylation calls; 61 differentially methylated regions were identified between haplotypes. Nearest features included classical imprinted genes, non-coding RNAs, and putative novel imprinted loci. The assembled mitogenome successfully resolved existing discordance between Felinae nuclear and mtDNA phylogenies. All assembly drafts were generated from 158 Gb of sequence using seven minION flow cells.
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Affiliation(s)
- Nicole Flack
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN 55108, USA
| | - Melissa Drown
- Department of Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN 55108, USA
| | - Carrie Walls
- Department of Animal Science, University of Minnesota, Saint Paul, MN 55108, USA
| | - Jay Pratte
- Bloomington Parks and Recreation, Miller Park Zoo, Bloomington, IL 61701, USA
| | - Adam McLain
- Department of Biology and Chemistry, SUNY Polytechnic Institute, Utica, NY 13502, USA
| | - Christopher Faulk
- Department of Animal Science, University of Minnesota, Saint Paul, MN 55108, USA
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10
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Foley NM, Mason VC, Harris AJ, Bredemeyer KR, Damas J, Lewin HA, Eizirik E, Gatesy J, Karlsson EK, Lindblad-Toh K, Springer MS, Murphy WJ, Andrews G, Armstrong JC, Bianchi M, Birren BW, Bredemeyer KR, Breit AM, Christmas MJ, Clawson H, Damas J, Di Palma F, Diekhans M, Dong MX, Eizirik E, Fan K, Fanter C, Foley NM, Forsberg-Nilsson K, Garcia CJ, Gatesy J, Gazal S, Genereux DP, Goodman L, Grimshaw J, Halsey MK, Harris AJ, Hickey G, Hiller M, Hindle AG, Hubley RM, Hughes GM, Johnson J, Juan D, Kaplow IM, Karlsson EK, Keough KC, Kirilenko B, Koepfli KP, Korstian JM, Kowalczyk A, Kozyrev SV, Lawler AJ, Lawless C, Lehmann T, Levesque DL, Lewin HA, Li X, Lind A, Lindblad-Toh K, Mackay-Smith A, Marinescu VD, Marques-Bonet T, Mason VC, Meadows JRS, Meyer WK, Moore JE, Moreira LR, Moreno-Santillan DD, Morrill KM, Muntané G, Murphy WJ, Navarro A, Nweeia M, Ortmann S, Osmanski A, Paten B, Paulat NS, Pfenning AR, Phan BN, Pollard KS, Pratt HE, Ray DA, Reilly SK, Rosen JR, Ruf I, Ryan L, Ryder OA, Sabeti PC, Schäffer DE, Serres A, Shapiro B, Smit AFA, Springer M, Srinivasan C, Steiner C, Storer JM, Sullivan KAM, Sullivan PF, Sundström E, Supple MA, Swofford R, Talbot JE, Teeling E, Turner-Maier J, Valenzuela A, Wagner F, Wallerman O, Wang C, Wang J, Weng Z, Wilder AP, Wirthlin ME, Xue JR, Zhang X. A genomic timescale for placental mammal evolution. Science 2023; 380:eabl8189. [PMID: 37104581 DOI: 10.1126/science.abl8189] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
The precise pattern and timing of speciation events that gave rise to all living placental mammals remain controversial. We provide a comprehensive phylogenetic analysis of genetic variation across an alignment of 241 placental mammal genome assemblies, addressing prior concerns regarding limited genomic sampling across species. We compared neutral genome-wide phylogenomic signals using concatenation and coalescent-based approaches, interrogated phylogenetic variation across chromosomes, and analyzed extensive catalogs of structural variants. Interordinal relationships exhibit relatively low rates of phylogenomic conflict across diverse datasets and analytical methods. Conversely, X-chromosome versus autosome conflicts characterize multiple independent clades that radiated during the Cenozoic. Genomic time trees reveal an accumulation of cladogenic events before and immediately after the Cretaceous-Paleogene (K-Pg) boundary, implying important roles for Cretaceous continental vicariance and the K-Pg extinction in the placental radiation.
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Affiliation(s)
- Nicole M Foley
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Victor C Mason
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Andrew J Harris
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, TX, USA
| | - Kevin R Bredemeyer
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, TX, USA
| | - Joana Damas
- The Genome Center, University of California, Davis, CA, USA
| | - Harris A Lewin
- The Genome Center, University of California, Davis, CA, USA
- Department of Evolution and Ecology, University of California, Davis, CA, USA
| | - Eduardo Eizirik
- School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - John Gatesy
- Division of Vertebrate Zoology, American Museum of Natural History, New York, NY, USA
| | - Elinor K Karlsson
- Program in Bioinformatics and Integrative Biology, UMass Chan Medical School, Worcester, MA 01605, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02139, USA
- Program in Molecular Medicine, University of Massachussetts Chan Medical School, Worcester, MA 01605, USA
| | - Kerstin Lindblad-Toh
- Broad Institute of MIT and Harvard, Cambridge, MA 02139, USA
- Department of Medical Biochemistry and Microbiology, Science for Life Laboratory, Uppsala University, 751 32 Uppsala, Sweden
| | - Mark S Springer
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, USA
| | - William J Murphy
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, TX, USA
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11
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Houck ML, Koepfli KP, Hains T, Khan R, Charter SJ, Fronczek JA, Misuraca AC, Kliver S, Perelman PL, Beklemisheva V, Graphodatsky A, Luo SJ, O'Brien SJ, Lim NTL, Chin JSC, Guerra V, Tamazian G, Omer A, Weisz D, Kaemmerer K, Sturgeon G, Gaspard J, Hahn A, McDonough M, Garcia-Treviño I, Gentry J, Coke RL, Janecka JE, Harrigan RJ, Tinsman J, Smith TB, Aiden EL, Dudchenko O. Chromosome-length genome assemblies and cytogenomic analyses of pangolins reveal remarkable chromosome counts and plasticity. Chromosome Res 2023; 31:13. [PMID: 37043058 DOI: 10.1007/s10577-023-09722-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 02/27/2023] [Accepted: 03/04/2023] [Indexed: 04/13/2023]
Abstract
We report the first chromosome-length genome assemblies for three species in the mammalian order Pholidota: the white-bellied, Chinese, and Sunda pangolins. Surprisingly, we observe extraordinary karyotypic plasticity within this order and, in female white-bellied pangolins, the largest number of chromosomes reported in a Laurasiatherian mammal: 2n = 114. We perform the first karyotype analysis of an African pangolin and report a Y-autosome fusion in white-bellied pangolins, resulting in 2n = 113 for males. We employ a novel strategy to confirm the fusion and identify the autosome involved by finding the pseudoautosomal region (PAR) in the female genome assembly and analyzing the 3D contact frequency between PAR sequences and the rest of the genome in male and female white-bellied pangolins. Analyses of genetic variability show that white-bellied pangolins have intermediate levels of genome-wide heterozygosity relative to Chinese and Sunda pangolins, consistent with two moderate declines of historical effective population size. Our results reveal a remarkable feature of pangolin genome biology and highlight the need for further studies of these unique and endangered mammals.
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Affiliation(s)
- Marlys L Houck
- Conservation Science and Wildlife Health, San Diego Zoo Wildlife Alliance, Escondido, CA, 92027, USA.
| | - Klaus-Peter Koepfli
- Smithsonian-Mason School of Conservation, George Mason University, Front Royal, VA, 22630, USA.
- Center for Species Survival, Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, VA, 22630, USA.
- Computer Technologies Laboratory, ITMO University, 197101, St. Petersburg, Russia.
| | - Taylor Hains
- Committee On Evolutionary Biology, University of Chicago, Chicago, IL, 60637, USA
| | - Ruqayya Khan
- The Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Suellen J Charter
- Conservation Science and Wildlife Health, San Diego Zoo Wildlife Alliance, Escondido, CA, 92027, USA
| | - Julie A Fronczek
- Conservation Science and Wildlife Health, San Diego Zoo Wildlife Alliance, Escondido, CA, 92027, USA
| | - Ann C Misuraca
- Conservation Science and Wildlife Health, San Diego Zoo Wildlife Alliance, Escondido, CA, 92027, USA
| | - Sergei Kliver
- Center for Evolutionary Hologenomics, The Globe Institute, The University of Copenhagen, 5A, Oester Farimagsgade, 1353, Copenhagen, Denmark
| | - Polina L Perelman
- Department of the Diversity and Evolution of Genomes, Institute of Molecular and Cellular Biology SB RAS, 630090, Novosibirsk, Russia
| | - Violetta Beklemisheva
- Department of the Diversity and Evolution of Genomes, Institute of Molecular and Cellular Biology SB RAS, 630090, Novosibirsk, Russia
| | - Alexander Graphodatsky
- Department of the Diversity and Evolution of Genomes, Institute of Molecular and Cellular Biology SB RAS, 630090, Novosibirsk, Russia
| | - Shu-Jin Luo
- The State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences (CLS), School of Life Sciences, Peking University, Beijing, 100871, China
| | - Stephen J O'Brien
- Laboratory of Genomic Diversity, Computer Technologies Laboratory, ITMO University, 197101, St. Petersburg, Russia
- Guy Harvey Oceanographic Center, Halmos College of Arts and Sciences, Nova Southeastern University, Fort Lauderdale, FL, 33004, USA
| | - Norman T-L Lim
- Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University, Singapore, 637616, Singapore
| | - Jason S C Chin
- Taipei Zoo, No. 30 Sec. 2 Xinguang Rd., Taipei, 11656, Taiwan
| | - Vanessa Guerra
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
- Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
| | - Gaik Tamazian
- Centre for Computational Biology, Peter the Great Saint Petersburg Polytechnic University, St. Petersburg, 195251, Russia
| | - Arina Omer
- The Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - David Weisz
- The Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | | | | | | | - Alicia Hahn
- Pittsburgh Zoo & Aquarium, PA, 15206, Pittsburgh, USA
| | | | | | - Jordan Gentry
- Center for Conservation and Research, San Antonio Zoo, San Antonio, TX, 78212, USA
| | - Rob L Coke
- Center for Conservation and Research, San Antonio Zoo, San Antonio, TX, 78212, USA
| | - Jan E Janecka
- Department of Biological Sciences, Bayer School of Natural and Environmental Sciences, Duquesne University, Pittsburgh, PA, 15282, USA
| | - Ryan J Harrigan
- Center for Tropical Research, Institute of the Environment and Sustainability, University of California, Los Angeles, CA, 90095, USA
| | - Jen Tinsman
- Center for Tropical Research, Institute of the Environment and Sustainability, University of California, Los Angeles, CA, 90095, USA
| | - Thomas B Smith
- Center for Tropical Research, Institute of the Environment and Sustainability, University of California, Los Angeles, CA, 90095, USA
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA, 90095, USA
| | - Erez Lieberman Aiden
- The Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
- Departments of Computer Science and Computational and Applied Mathematics, Rice University, Houston, TX, 77030, USA
- Center for Theoretical and Biological Physics, Rice University, Houston, TX, 77030, USA
- Broad Institute of Harvard and Massachusetts Institute of Technology (MIT), Cambridge, MA, 02139, USA
| | - Olga Dudchenko
- The Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA.
- Center for Theoretical and Biological Physics, Rice University, Houston, TX, 77030, USA.
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12
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Yakupova A, Tomarovsky A, Totikov A, Beklemisheva V, Logacheva M, Perelman PL, Komissarov A, Dobrynin P, Krasheninnikova K, Tamazian G, Serdyukova NA, Rayko M, Bulyonkova T, Cherkasov N, Pylev V, Peterfeld V, Penin A, Balanovska E, Lapidus A, OBrien SJ, Graphodatsky A, Koepfli KP, Kliver S. Chromosome-Length Assembly of the Baikal Seal (Pusa sibirica) Genome Reveals a Historically Large Population Prior to Isolation in Lake Baikal. Genes (Basel) 2023; 14:genes14030619. [PMID: 36980891 PMCID: PMC10048373 DOI: 10.3390/genes14030619] [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: 12/21/2022] [Revised: 01/31/2023] [Accepted: 02/24/2023] [Indexed: 03/05/2023] Open
Abstract
Pusa sibirica, the Baikal seal, is the only extant, exclusively freshwater, pinniped species. The pending issue is, how and when they reached their current habitat—the rift lake Baikal, more than three thousand kilometers away from the Arctic Ocean. To explore the demographic history and genetic diversity of this species, we generated a de novo chromosome-length assembly, and compared it with three closely related marine pinniped species. Multiple whole genome alignment of the four species compared with their karyotypes showed high conservation of chromosomal features, except for three large inversions on chromosome VI. We found the mean heterozygosity of the studied Baikal seal individuals was relatively low (0.61 SNPs/kbp), but comparable to other analyzed pinniped samples. Demographic reconstruction of seals revealed differing trajectories, yet remarkable variations in Ne occurred during approximately the same time periods. The Baikal seal showed a significantly more severe decline relative to other species. This could be due to the difference in environmental conditions encountered by the earlier populations of Baikal seals, as ice sheets changed during glacial–interglacial cycles. We connect this period to the time of migration to Lake Baikal, which occurred ~3–0.3 Mya, after which the population stabilized, indicating balanced habitat conditions.
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Affiliation(s)
- Aliya Yakupova
- Computer Technologies Laboratory, ITMO University, 19701 Saint Petersburg, Russia
- Correspondence: (A.Y.); (A.G.)
| | - Andrey Tomarovsky
- Computer Technologies Laboratory, ITMO University, 19701 Saint Petersburg, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
- Department of the Diversity and Evolution of Genomes, Institute of Molecular and Cellular Biology SB RAS, 630090 Novosibirsk, Russia
| | - Azamat Totikov
- Computer Technologies Laboratory, ITMO University, 19701 Saint Petersburg, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
- Department of the Diversity and Evolution of Genomes, Institute of Molecular and Cellular Biology SB RAS, 630090 Novosibirsk, Russia
| | - Violetta Beklemisheva
- Department of the Diversity and Evolution of Genomes, Institute of Molecular and Cellular Biology SB RAS, 630090 Novosibirsk, Russia
| | - Maria Logacheva
- Skolkovo Institute of Science and Technology, 121205 Moscow, Russia
| | - Polina L. Perelman
- Department of the Diversity and Evolution of Genomes, Institute of Molecular and Cellular Biology SB RAS, 630090 Novosibirsk, Russia
| | - Aleksey Komissarov
- Applied Genomics Laboratory, SCAMT Institute, ITMO University, 9 Ulitsa Lomonosova, 191002 Saint Petersburg, Russia
| | - Pavel Dobrynin
- Computer Technologies Laboratory, ITMO University, 19701 Saint Petersburg, Russia
- Human Genetics Laboratory, Vavilov Institute of General Genetics RAS, 119991 Moscow, Russia
| | | | - Gaik Tamazian
- Centre for Computational Biology, Peter the Great Saint Petersburg Polytechnic University, 195251 St. Petersburg, Russia
| | - Natalia A. Serdyukova
- Department of the Diversity and Evolution of Genomes, Institute of Molecular and Cellular Biology SB RAS, 630090 Novosibirsk, Russia
| | - Mike Rayko
- Center for Bioinformatics and Algorithmic Biotechnology, St. Petersburg State University, 199034 St. Petersburg, Russia
| | - Tatiana Bulyonkova
- Laboratory of Mixed Computations, A.P. Ershov Institute of Informatics Systems SB RAS, 630090 Novosibirsk, Russia
| | - Nikolay Cherkasov
- Centre for Computational Biology, Peter the Great Saint Petersburg Polytechnic University, 195251 St. Petersburg, Russia
| | - Vladimir Pylev
- Laboratory of Human Population Genetics, Research Centre for Medical Genetics, 115522 Moscow, Russia
| | - Vladimir Peterfeld
- Baikal Branch of State Research and Industrial Center of Fisheries, 670034 Ulan-Ude, Russia
| | - Aleksey Penin
- Institute for Information Transmission Problems of the Russian Academy of Sciences, 127051 Moscow, Russia
| | - Elena Balanovska
- Laboratory of Human Population Genetics, Research Centre for Medical Genetics, 115522 Moscow, Russia
| | - Alla Lapidus
- Center for Bioinformatics and Algorithmic Biotechnology, St. Petersburg State University, 199034 St. Petersburg, Russia
| | - DNA Zoo Consortium
- The Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Stephen J. OBrien
- Guy Harvey Oceanographic Center, Halmos College of Arts and Sciences, NOVA Southeastern University, Fort Lauderdale, FL 33004, USA
| | - Alexander Graphodatsky
- Department of the Diversity and Evolution of Genomes, Institute of Molecular and Cellular Biology SB RAS, 630090 Novosibirsk, Russia
- Correspondence: (A.Y.); (A.G.)
| | - Klaus-Peter Koepfli
- Smithsonian-Mason School of Conservation, George Mason University, 1500 Remount Road, Front Royal, VA 22630, USA
- Center for Species Survival, Smithsonian’s National Zoo and Conservation Biology Institute, 1500 Remount Road, Front Royal, VA 22630, USA
| | - Sergei Kliver
- Center for Evolutionary Hologenomics, The Globe Institute, The University of Copenhagen, 5A, Oester Farimagsgade, 1353 Copenhagen, Denmark
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13
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Steinberg ER, Bressa MJ, Mudry MD. Sex chromosome systems in Neotropical Primates: What have we learnt so far from cytogenetics and genomics? J Evol Biol 2022; 35:1589-1600. [PMID: 35731796 DOI: 10.1111/jeb.14039] [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: 01/30/2022] [Revised: 05/10/2022] [Accepted: 05/26/2022] [Indexed: 11/29/2022]
Abstract
Neotropical Primates (Platyrrhini) show great diversity in their life histories, ecology, behaviour and genetics. This diversity extends to their chromosome complements, both to autosomes and to sex chromosomes. In this contribution, we will review what is currently known about sex chromosomes in this group, both from cytogenetic and from genomic evidence. The X and Y chromosomes in Neotropical Primates, also known as New World Monkeys, have striking structural differences compared with Old World Monkeys when Catarrhini sex chromosomes are considered. The XY bivalent displays a different meiotic behaviour in prophase I, and their Y chromosome shows extensive genomic differences. Even though the most widespread sex chromosome system is the XX/XY and thus considered the ancestral one for Platyrrhini, modifications of this sexual system are observed within this group. Multiple sex chromosome systems originated from Y-autosome translocations were described in several genera (Aotus, Callimico and Alouatta). In the howler monkeys, genus Alouatta, an independent origin of the sexual systems in South American and Mesoamerican species was postulated. All the above-mentioned evidence suggests that the Y chromosome of Platyrrhini has a different evolutionary history compared with the Catarrhini Y. There is still much to understand regarding their sex chromosome systems.
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Affiliation(s)
- Eliana Ruth Steinberg
- Grupo de Investigación en Biología Evolutiva (GIBE). Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Departamento de Ecología, Genética y Evolución (EGE), Facultad de Ciencias Exactas y Naturales (FCEyN), Universidad de Buenos Aires (UBA), CONICET, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - María José Bressa
- Grupo de Citogenética de Insectos. Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Departamento de Ecología, Genética y Evolución (EGE), Facultad de Ciencias Exactas y Naturales (FCEyN), Universidad de Buenos Aires (UBA), CONICET, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Marta Dolores Mudry
- Grupo de Investigación en Biología Evolutiva (GIBE). Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Departamento de Ecología, Genética y Evolución (EGE), Facultad de Ciencias Exactas y Naturales (FCEyN), Universidad de Buenos Aires (UBA), CONICET, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
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14
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Moore EC, Thomas GWC, Mortimer S, Kopania EEK, Hunnicutt KE, Clare-Salzler ZJ, Larson EL, Good JM. The Evolution of Widespread Recombination Suppression on the Dwarf Hamster (Phodopus) X Chromosome. Genome Biol Evol 2022; 14:evac080. [PMID: 35642315 PMCID: PMC9185382 DOI: 10.1093/gbe/evac080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2022] [Indexed: 11/24/2022] Open
Abstract
The X chromosome of therian mammals shows strong conservation among distantly related species, limiting insights into the distinct selective processes that have shaped sex chromosome evolution. We constructed a chromosome-scale de novo genome assembly for the Siberian dwarf hamster (Phodopus sungorus), a species reported to show extensive recombination suppression across an entire arm of the X chromosome. Combining a physical genome assembly based on shotgun and long-range proximity ligation sequencing with a dense genetic map, we detected widespread suppression of female recombination across ∼65% of the Phodopus X chromosome. This region of suppressed recombination likely corresponds to the Xp arm, which has previously been shown to be highly heterochromatic. Using additional sequencing data from two closely related species (P. campbelli and P. roborovskii), we show that recombination suppression on Xp appears to be independent of major structural rearrangements. The suppressed Xp arm was enriched for several transposable element families and de-enriched for genes primarily expressed in placenta, but otherwise showed similar gene densities, expression patterns, and rates of molecular evolution when compared to the recombinant Xq arm. Phodopus Xp gene content and order was also broadly conserved relative to the more distantly related rat X chromosome. These data suggest that widespread suppression of recombination has likely evolved through the transient induction of facultative heterochromatin on the Phodopus Xp arm without major changes in chromosome structure or genetic content. Thus, substantial changes in the recombination landscape have so far had relatively subtle influences on patterns of X-linked molecular evolution in these species.
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Affiliation(s)
- Emily C. Moore
- Division of Biological Sciences, The University of Montana, Missoula, Montana, 59812, USA
| | - Gregg W. C. Thomas
- Division of Biological Sciences, The University of Montana, Missoula, Montana, 59812, USA
| | - Sebastian Mortimer
- Division of Biological Sciences, The University of Montana, Missoula, Montana, 59812, USA
| | - Emily E. K. Kopania
- Division of Biological Sciences, The University of Montana, Missoula, Montana, 59812, USA
| | - Kelsie E. Hunnicutt
- Department of Biological Sciences, The University of Denver, Denver, Colorado, 80208, USA
| | | | - Erica L. Larson
- Department of Biological Sciences, The University of Denver, Denver, Colorado, 80208, USA
| | - Jeffrey M. Good
- Division of Biological Sciences, The University of Montana, Missoula, Montana, 59812, USA
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15
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Abstract
We found the three-dimensional (3D) structure of chromatin at the chromosome level to be highly conserved for more than 50 million y of carnivore evolution. Intrachromosomal contacts were maintained even after chromosome rearrangements within carnivore lineages, demonstrating that the maintenance of 3D chromatin architecture is essential for conserved genome functions. These discoveries enabled the identification of orthologous chromosomal DNA segments among related species, a method we call 3D comparative scaffotyping. The method has application for putative chromosome assignment of chromosome-scale DNA sequence scaffolds produced by de novo genome sequencing. Broadly applied to biodiversity genome sequencing efforts, the approach can reduce costs associated with karyotyping and the physical mapping of DNA segments to chromosomes. High throughput chromatin conformation capture (Hi-C) of leukocyte DNA was used to investigate the evolutionary stability of chromatin conformation at the chromosomal level in 11 species from three carnivore families: Felidae, Canidae, and Ursidae. Chromosome-scale scaffolds (C-scaffolds) of each species were initially used for whole-genome alignment to a reference genome within each family. This approach established putative orthologous relationships between C-scaffolds among the different species. Hi-C contact maps for all C-scaffolds were then visually compared and found to be distinct for a given reference chromosome or C-scaffold within a species and indistinguishable for orthologous C-scaffolds having a 1:1 relationship within a family. The visual patterns within families were strongly supported by eigenvectors from the Hi-C contact maps. Analysis of Hi-C contact maps and eigenvectors across the three carnivore families revealed that most cross-family orthologous subchromosomal fragments have a conserved three-dimensional (3D) chromatin structure and thus have been under strong evolutionary constraint for ∼54 My of carnivore evolution. The most pronounced differences in chromatin conformation were observed for the X chromosome and the red fox genome, whose chromosomes have undergone extensive rearrangements relative to other canids. We also demonstrate that Hi-C contact map pattern analysis can be used to accurately identify orthologous relationships between C-scaffolds and chromosomes, a method we termed “3D comparative scaffotyping.” This method provides a powerful means for estimating karyotypes in de novo sequenced species that have unknown karyotype and no physical mapping information.
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16
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Bredemeyer KR, Seabury CM, Stickney MJ, McCarrey JR, vonHoldt BM, Murphy WJ. Rapid Macrosatellite Evolution Promotes X-Linked Hybrid Male Sterility in a Feline Interspecies Cross. Mol Biol Evol 2021; 38:5588-5609. [PMID: 34519828 PMCID: PMC8662614 DOI: 10.1093/molbev/msab274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The sterility or inviability of hybrid offspring produced from an interspecific mating result from incompatibilities between parental genotypes that are thought to result from divergence of loci involved in epistatic interactions. However, attributes contributing to the rapid evolution of these regions also complicates their assembly, thus discovery of candidate hybrid sterility loci is difficult and has been restricted to a small number of model systems. Here we reported rapid interspecific divergence at the DXZ4 macrosatellite locus in an interspecific cross between two closely related mammalian species: the domestic cat (Felis silvestris catus) and the Jungle cat (Felis chaus). DXZ4 is an interesting candidate due to its structural complexity, copy number variability, and described role in the critical yet complex biological process of X-chromosome inactivation. However, the full structure of DXZ4 was absent or incomplete in nearly every available mammalian genome assembly given its repetitive complexity. We compared highly continuous genomes for three cat species, each containing a complete DXZ4 locus, and discovered that the felid DXZ4 locus differs substantially from the human ortholog, and that it varies in copy number between cat species. Additionally, we reported expression, methylation, and structural conformation profiles of DXZ4 and the X chromosome during stages of spermatogenesis that have been previously associated with hybrid male sterility. Collectively, these findings suggest a new role for DXZ4 in male meiosis and a mechanism for feline interspecific incompatibility through rapid satellite divergence.
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Affiliation(s)
- Kevin R Bredemeyer
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, TX, USA
| | | | - Mark J Stickney
- Veterinary Medical Teaching Hospital, Texas A&M University, College Station, TX, USA
| | - John R McCarrey
- Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA
| | | | - William J Murphy
- Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, TX, USA
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