2025-04-07 京都大学,広島大学,基礎生物学研究所,近畿大学,科学技術振興機構
<関連情報>
- https://www.jst.go.jp/pr/announce/20250407/index.html
- https://www.jst.go.jp/pr/announce/20250407/pdf/20250407.pdf
- https://www.cell.com/cell-reports/fulltext/S2211-1247(25)00274-8
ゼニゴケ類における共性の収斂進化に関するMarchantia quadrataゲノムからの洞察 Insights into convergent evolution of cosexuality in liverworts from the Marchantia quadrata genome
Giacomo Potente ∙ Yukiko Yasui, yasui ∙ Eita Shimokawa∙ … ∙ Masaki Shimamura ∙ Takayuki Kohchi ∙ Péter Szövényi
Cell Reports Published:April 2, 2025
DOI:https://doi.org/10.1016/j.celrep.2025.115503
Graphical abstract
Highlights
- Liverworts evolving cosexuality retain the male (V) but lose the female (U) sex chromosome
- Essential genes of the U chromosome are maintained on the autosomes
- The feminizer gene acquires new regulation to enable both male and female functions
- Evolution of cosexuality followed a similar pattern twice independently in liverworts
Summary
Sex chromosomes are expected to coevolve with their respective sex, potentially disfavoring their co-occurrence as cosexuality evolves. This effect is expected to be stronger where sex chromosomes are restricted to one sex, such as in plants expressing sex in their haploid stage. We assess this hypothesis in liverworts with U/V sex chromosomes, ancestral dioicy, and several independent transitions to monoicy (cosexuality). We report the chromosome-level genome assembly of Marchantia quadrata, which recently evolved monoicy, and perform comparative genomic analyses with its dioicous relative M. polymorpha. We find that monoicy evolved via retention of the V chromosome as a small ninth chromosome, complete loss of the U chromosome, and translocation of key U-linked genes to autosomes, among which the major sex-determining gene (Feminizer) acquired environmental/developmental regulation. Our findings parallel recent observations on Ricciocarpos natans, which evolved monoicy independently, suggesting genetic constraints that may make transitions to monoicy predictable in liverworts.
