2026-09-18 基礎生物学研究所,お茶の水女子大学,京都府立大学,名古屋大学
図1: 本研究で明らかになった植物の低分子量GTPaseのクロストーク
＜関連情報＞
REAP1/ SWAP70は、有性生殖中にRAB5とROPのシグナル伝達を統合する REAP1/AtSWAP70 integrates RAB5 and ROP signalling during sexual reproduction
Emi Ito, Natalia Julia Rzepecka, Yoko Ito, Tomoko Hirano, Kazuo Ebine, Yoshihisa Oda, Masa H. Sato, Akihiko Nakano, Tomohiro Uemura & Takashi Ueda
Nature Plants Published:17 September 2026
DOI:https://doi.org/10.1038/s41477-026-02368-8
Abstract
Small GTPases of the Ras superfamily are critical regulators of diverse cellular processes. While crosstalk between their signalling pathways has been documented in animals, similar mechanisms remain unexplored in plants, where small GTPases have undergone unique evolutionary diversification. Here we identify REAP1/AtSWAP70 as an effector in Arabidopsis thaliana that interacts with the active forms of both canonical RAB5 and the plant-specific RAB5, ARA6. Remarkably, REAP1 also binds to active ROP7, a plant-unique Rac-type GTPase, via its Dbl homology domain. REAP1 localizes to endosomes and facilitates ROP7 recruitment from the plasma membrane, a process dependent on RAB5 activity. Genetic analyses reveal that the RAB5–REAP1–ROP7 signalling cascade is essential for gametogenesis, impacting pollen viability and development. This study provides evidence of functional crosstalk between RAB and ROP signalling in plants, unveiling a layer of regulatory complexity in plant GTPase signalling during plant reproduction.
