Membrane nanodomains to shape plant cellular functions and signaling

Plasma membrane (PM) nanodomains have emerged as pivotal elements in the regulation of plant cellular functions and signal transduction. These nanoscale membrane regions, enriched in specific lipids and proteins, behave as regulatory/signaling hubs spatially and temporally coordinating critical cellular functions. In this review, we first examine the mechanisms underlying the formation and maintenance of PM nanodomains in plant cells, highlighting the roles of PM lipid composition, protein oligomerization and interactions with cytoskeletal and cell wall components. Then, we discuss how nanodomains act as organizing centers by mediating protein-protein interactions that orchestrate essential processes such as symbiosis, defense against pathogens, ion transport or hormonal and reactive oxygen species (ROS) signaling. Finally, we introduce the concept of nanoenvironments, where localized physicochemical variations are generated in the very close proximity of PM nanodomains, in response to stimuli. After decoding by a dedicated machinery likely localized in the vicinity of nanodomains, this enrichment of secondary messengers, such as ROS or Ca²⁺, would allow specific downstream cellular responses. This review provides insights into the dynamic nature of nanodomains and proposes future research to better understand their contribution to the intricate signaling networks that govern plant development and stress responses.