植物免疫分泌肽PIP1参与气孔运动调控

Stomata are leaf surface localized microscopic pores and enclosed by pairs of guard cells, and which serve gates for both water vapor loss and CO2 absorption, as well as entries of plant pathogen aggression. The pathogen or pathogen-associated molecular patterns (PAMPs) induced plant PIP1 secretion and thus to amplify plant immunity. Here, we report that the PIP1, a member of PAMP-induced secreted peptide, could mimic flg22 or ABA effect to close stomata of Arabidopsis thaliana. Further experiments revealed that, like the physiological roles of ABA, the PIP1 could activate Slow-type anion channels of guard cells to facilitate the anion efflux, and also could induce the reactive oxygen species (ROS) generation in guard cell cytosol, and activate Ca2+ permeable channel currents as well. The common second messengers as ROS, Ca2+ influx and anion efflux, were both employed by the drought and plant pathogen regulated stomatal movements, which suggest the comprehensive interaction of plant signaling in response to abiotic and biotic stresses.??