AUTHOR=Zhang Huiying , Liu Xin , Zhang Xiyong , Qin Ningning , Xu Kaifang , Yin Weihua , Zheng Yueqin , Song Yuanyuan , Zeng Rensen , Liu Jian 

TITLE=Phosphoinositide 3-Kinase Promotes Oxidative Burst, Stomatal Closure and Plant Immunity in Bacterial Invasion

JOURNAL=Frontiers in Plant Science

VOLUME=10

YEAR=2020

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2019.01740

DOI=10.3389/fpls.2019.01740

ISSN=1664-462X

ABSTRACT=<p>Phosphoinositide 3-kinase (PI3K) plays a vital role in plant response to abiotic stress. However, the role of PI3K in plant immunity is largely unknown. This study showed that PI3K enhanced <italic>Arabidopsis</italic> resistance to <italic>Pseudomonas syringae</italic> pv <italic>tomato</italic> DC3000 (<italic>Pst</italic> DC3000) and <italic>Pst</italic> DC3000 (<italic>avrRpt2</italic>). Overexpression of <italic>AtVPS34</italic> promoted stomatal closure while PI3K inhibitors blocked that after spray inoculation. Additionally, gene expression of <italic>AtVPS34</italic> was increased upon infection by <italic>Pst</italic> DC3000 (<italic>avrRpt2</italic>), and SA upregulated <italic>AtVPS34</italic> gene expression in this process. Furthermore, overexpression of <italic>AtVPS34</italic> enhanced <italic>PR</italic> gene expression after syringe infiltration with <italic>Pst</italic> DC3000 (<italic>avrRpt2</italic>), while PI3K inhibitors inhibited that. The production of hydrogen peroxide and the expression of gene encoding antioxidant enzyme were both enhanced in <italic>AtVPS34</italic> overexpressing lines after spray inoculation or syringe infiltration with <italic>Pst</italic> DC3000 (<italic>avrRpt2</italic>). Collectively, these results unraveled a novel and broad role of PI3K in plant immunity which promoted stomatal closure and <italic>PR</italic> gene expression possibly <italic>via</italic> regulating ROS production.</p>