ROP Signaling in Plant Seed Germination Under Abiotic Stress

Seed germination is a crucial phase where a plant embryo transitions from dormancy to active growth, emerging as a seedling. This intricate process is highly susceptible to environmental cues, particularly abiotic stress factors including drought, salinity, and temperature extremes, which can profoundly influence both germination success and subsequent plant development. Among the various cellular components that modulate plant responses to these stresses, Rho of Plants (ROP) emerges as a pivotal regulator. Under abiotic stress, ROP signaling components integrate with the core abscisic acid (ABA) signaling pathway by regulating gene transcription and protein stability, modulating subcellular localization, converting protein activity, and engaging in competitive interactions. This review summarizes recent findings on roles of ROP signaling in regulating plant adaptive responses to abiotic stress, whilst explores potential involvement of ROPs in seed germination. This review summarizes the effects of ROP proteins and their effectors, such as GEF, on the seed germination process. It preliminarily elucidates the crosstalk mechanisms between these proteins and the ABA signaling pathway, thereby gaining a deeper understanding of the role of ROP signaling in regulating plant adaptive responses to abiotic stresses.