The plant ARF GTPase family: current perspectives in membrane trafficking, cellular signalling and new paradigms

Abstract

Plant ADP-ribosylation factor (ARF) and ARF-like (ARL) proteins are subfamily members of the small GTPases superfamily. They are pivotal regulators of dynamic cellular processes, notably vesicle trafficking, through their ability to switch conformations between GTP- and GDP-bound states. Despite their high conservation across species, the diversity and functions of ARF/ARL proteins, along with their regulatory guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs), vary considerably among organisms, reflecting species-specific roles. In plants compared to mammals, the ARF subfamily and its cognate GEFs and GAPs family remain understudied. Recent advances have begun to unveil their biochemical activities and physiological significance in plant development and stress responses. This review synthesizes current knowledge on the plant ARF subfamily, emphasizing their regulatory interactions and physiological contexts, and highlights avenues for future research into their roles in cell physiological signaling pathways critical for plant growth and adaptation.