In rose, transcription factor PTM balances growth and drought survival via PIP2;1 aquaporin

Plants have evolved sophisticated systems in response to environmental changes, and growth arrest is a common strategy used to enhance stress tolerance. Despite the growth–survival trade-off being essential to the shaping of plant productivity, the mechanisms balancing growth and survival remain largely unknown. Aquaporins play a crucial role in growth and stress responses by controlling water transport across membranes. Here, we show that RhPIP2;1, an aquaporin from rose ( Rosa sp.), interacts with a membrane-tethered MYB protein, RhPTM. Water deficiency triggers nuclear translocation of the RhPTM C terminus. Silencing of RhPTM causes continuous growth under drought stress and a consequent decrease in survival rate. RNA sequencing (RNA-seq) indicated that RhPTM influences the expression of genes related to carbohydrate metabolism. Water deficiency induces phosphorylation of RhPIP2;1 at Ser 273, which is sufficient to promote nuclear translocation of the RhPTM C terminus. These results indicate that the RhPIP2;1-RhPTM module serves as a key player in orchestrating the trade-off between growth and stress survival in Rosa . Functional interaction between an aquaporin and a membrane-tethered growth suppressor MYB transcription factor leads to activation of the latter, establishing a link between hydraulics and transcriptional control.