期刊
PLOS GENETICS
卷 18, 期 2, 页码 -出版社
PUBLIC LIBRARY SCIENCE
DOI: 10.1371/journal.pgen.1010040
关键词
-
资金
- Ministry of Economy, Industry and Competitiveness [CGL2017-83802-P, CGL2014-53106-P]
- Spanish Ministry of Science and Innovation [PID2020-112557GGB-I00]
- Agenciade Gestio dAjuts Universitaris ide Recerca, AGAUR [SGR1215]
- FPU predoctoral fellowship from the Ministry of Science, Innovation and University [FPU18/03867]
- FPI predoctoral fellowship from the Ministry of Economy, Industry and Competitiveness [BES-2015-072924]
- Australian Research Council [DP170101147, DP180100931, DP210103512]
The study reveals the features of meiotic cell division in marsupials, particularly the strategies of sex chromosome pairing, recombination, and telomere homeostasis. The researchers found that marsupials have non-canonical meiotic strategies, including alternative mechanisms for controlling telomere length in the paternal parent. These findings provide new insights into the diversity of meiotic strategies in mammals.
Author summaryThe generation of haploid gametes is a hallmark of sexual reproduction. And this is accomplished by a complex, albeit tightly regulated, reductional cell division called meiosis. Although meiosis has been extensively studied in eutherian mammal model species, our understanding of the mechanisms regulating chromosome synapsis, recombination and segregation during meiosis progression is still incomplete especially in non-eutherian mammals. To fill this gap and capture the diversity of meiotic strategies among mammals, we study previously uncharacterised representative marsupial species, an evolutionary assemblage that last shared a common ancestry more than 80 million years ago. We uncover novel, hence non-canonical, strategies for sex chromosome pairing, DNA repair, recombination and transcription. Most importantly, we reveal the uniqueness of marsupial meiosis, which includes the unprecedented detection of alternative mechanism (ALT) for the paternal control of telomere length during prophase I. Our findings suggest that ALT (previously only associated to cancer cells) could play a role in telomere homeostasis in mammalian germ cells. During meiotic prophase I, homologous chromosomes pair, synapse and recombine in a tightly regulated process that ensures the generation of genetically variable haploid gametes. Although the mechanisms underlying meiotic cell division have been well studied in model species, our understanding of the dynamics of meiotic prophase I in non-traditional model mammals remains in its infancy. Here, we reveal key meiotic features in previously uncharacterised marsupial species (the tammar wallaby and the fat-tailed dunnart), plus the fat-tailed mouse opossum, with a focus on sex chromosome pairing strategies, recombination and meiotic telomere homeostasis. We uncovered differences between phylogroups with important functional and evolutionary implications. First, sex chromosomes, which lack a pseudo-autosomal region in marsupials, had species specific pairing and silencing strategies, with implications for sex chromosome evolution. Second, we detected two waves of gamma H2AX accumulation during prophase I. The first wave was accompanied by low gamma H2AX levels on autosomes, which correlated with the low recombination rates that distinguish marsupials from eutherian mammals. In the second wave, gamma H2AX was restricted to sex chromosomes in all three species, which correlated with transcription from the X in tammar wallaby. This suggests non-canonical functions of gamma H2AX on meiotic sex chromosomes. Finally, we uncover evidence for telomere elongation in primary spermatocytes of the fat-tailed dunnart, a unique strategy within mammals. Our results provide new insights into meiotic progression and telomere homeostasis in marsupials, highlighting the importance of capturing the diversity of meiotic strategies within mammals.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据