Plant Aquaporin AtPIP1;4 Links Apoplastic H 2 O 2 Induction to Disease Immunity Pathways

作者：Shan Tian, Xiaobing Wang, Ping Li, Hao Wang, Hongtao Ji, Junyi Xie, Qinglei Qiu, Dan Shen, Hansong Dong · 发表于：PLANT PHYSIOLOGY · 年份：2016 · DOI：10.1104/pp.15.01237 · 被引用次数：298 · 研究领域：Legume Nitrogen Fixing Symbiosis、Plant Stress Responses and Tolerance、Plant-Microbe Interactions and Immunity

Hydrogen peroxide (H2O2) is a stable component of reactive oxygen species, and its production in plants represents the successful recognition of pathogen infection and pathogen-associated molecular patterns (PAMPs). This production of H2O2 is typically apoplastic but is subsequently associated with intracellular immunity pathways that regulate disease resistance, such as systemic acquired resistance and PAMP-triggered immunity. Here, we elucidate that an Arabidopsis (Arabidopsis thaliana) aquaporin (i.e. the plasma membrane intrinsic protein AtPIP1;4) acts to close the cytological distance between H2O2 production and functional performance. Expression of the AtPIP1;4 gene in plant leaves is inducible by a bacterial pathogen, and the expression accompanies H2O2 accumulation in the cytoplasm. Under de novo expression conditions, AtPIP1;4 is able to mediate the translocation of externally applied H2O2 into the cytoplasm of yeast (Saccharomyces cerevisiae) cells. In plant cells treated with H2O2, AtPIP1;4 functions as an effective facilitator of H2O2 transport across plasma membranes and mediates the translocation of externally applied H2O2 from the apoplast to the cytoplasm. The H2O2-transport role of AtPIP1;4 is essentially required for the cytoplasmic import of apoplastic H2O2 induced by the bacterial pathogen and two typical PAMPs in the absence of induced production of intracellular H2O2 As a consequence, cytoplasmic H2O2 quantities increase substantially while systemic acqu...