Diversity of reptile sex chromosome evolution revealed by cytogenetic and linked-read sequencing

Ze-Xian Zhu; Kazumi Matsubara; Foyez Shams; Jason Dobry; Erik Wapstra; Tony Gamble; Stephen D. Sarre; Arthur Georges; Jennifer A. Marshall Graves; Qi Zhou; Tariq Ezaz

doi:10.24272/j.issn.2095-8137.2022.127

Volume 43 Issue 5

Sep. 2022

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Article Navigation > Zoological Research > 2022 > 43(5): 719-733

Ze-Xian Zhu, Kazumi Matsubara, Foyez Shams, Jason Dobry, Erik Wapstra, Tony Gamble, Stephen D. Sarre, Arthur Georges, Jennifer A. Marshall Graves, Qi Zhou, Tariq Ezaz. Diversity of reptile sex chromosome evolution revealed by cytogenetic and linked-read sequencing. Zoological Research, 2022, 43(5): 719-733. doi: 10.24272/j.issn.2095-8137.2022.127

Citation:

Ze-Xian Zhu, Kazumi Matsubara, Foyez Shams, Jason Dobry, Erik Wapstra, Tony Gamble, Stephen D. Sarre, Arthur Georges, Jennifer A. Marshall Graves, Qi Zhou, Tariq Ezaz. Diversity of reptile sex chromosome evolution revealed by cytogenetic and linked-read sequencing. Zoological Research, 2022, 43(5): 719-733. doi: 10.24272/j.issn.2095-8137.2022.127

Citation:

Ze-Xian Zhu, Kazumi Matsubara, Foyez Shams, Jason Dobry, Erik Wapstra, Tony Gamble, Stephen D. Sarre, Arthur Georges, Jennifer A. Marshall Graves, Qi Zhou, Tariq Ezaz. Diversity of reptile sex chromosome evolution revealed by cytogenetic and linked-read sequencing. Zoological Research, 2022, 43(5): 719-733. doi: 10.24272/j.issn.2095-8137.2022.127

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Diversity of reptile sex chromosome evolution revealed by cytogenetic and linked-read sequencing

doi: 10.24272/j.issn.2095-8137.2022.127

1.
MOE Laboratory of Biosystems Homeostasis and Protection and Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
2.
Institute for Applied Ecology, University of Canberra, Canberra 2601, Australia
3.
School of Biological Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia
4.
Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin 52322, USA
5.
School of Life Science, La Trobe University, Melbourne 3168 Australia
6.
Department of Neuroscience and Developmental Biology, University of Vienna, Vienna 1030, Austria
7.
Center for Reproductive Medicine, The 2nd Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310009, China

#Authors contributed equally to this work

Funds: This work was supported by the National Natural Science Foundation of China (32170415, 32061130208), Natural Science Foundation of Zhejiang Province (LD19C190001) and European Research Council Starting Grant (677696) to Q.Z. T.E. was supported by an ARC FT (FT110100733). This project was also partially supported by ARC DP (DP110102262) led by T.E. and University of Canberra Strategic Research Fund awarded to T.E. K.M. was supported by an ARC DP (DP110102262) led by T.E. T.G. was supported by NSF (IOS1146820). F.S. and J.D. were supported by the University of Canberra postgraduate research scholarships ^†Current affiliation: Department of Environmental Biology, College of Bioscience and Biotechnology, Chubu University, Kasugai, Aichi 487-8501, Japan

More Information

Corresponding author: E-mail: zhouqi1982@zju.edu.cn; Tariq.Ezaz@canberra.edu.au
Received Date: 2022-05-30
Accepted Date: 2022-07-25

Published Online: 2022-07-28

Publish Date: 2022-09-18

Abstract

Abstract

Reptile sex determination is attracting much attention because the great diversity of sex-determination and dosage compensation mechanisms permits us to approach fundamental questions about mechanisms of sex chromosome turnover. Recent studies have made significant progress in better understanding diversity and conservation of reptile sex chromosomes, with however no reptile master sex determination genes identified. Here we describe an integrated genomics and cytogenetics pipeline, combining probes generated from the microdissected sex chromosomes with transcriptome and genome sequencing to explore the sex chromosome diversity in non-model Australian reptiles. We tested our pipeline on a turtle, two species of geckos, and a monitor lizard. Genes identified on sex chromosomes were compared to the chicken genome to identify homologous regions among the four species. We identified candidate sex determining genes within these regions, including conserved vertebrate sex-determining genes pdgfa, pdgfra amh and wt1, and demonstrated their testis or ovary-specific expression. All four species showed gene-by-gene rather than chromosome-wide dosage compensation. Our results imply that reptile sex chromosomes originated by independent acquisition of sex-determining genes on different autosomes, as well as translocations between different ancestral macro- and microchromosomes. We discuss the evolutionary drivers of the slow differentiation and turnover of reptile sex chromosomes.
- Sex determination,
- Reptiles,
- Genomics,
- Cytogenetics,
- Sex chromosome turnover

#Authors contributed equally to this work

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References(99)

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