The Fundamental Role of NOX Family Proteins in Plant Immunity and Their Regulation

NADPH oxidases (NOXs), also known as respiratory burst oxidase homologs (RBOHs), are the major source of reactive oxygen species (ROS), and are involved in many important processes in plants such as regulation of acclimatory signaling and programmed cell death (PCD). Increasing evidence shows that NOXs play crucial roles in plant immunity and their functions in plant immune responses are not as separate individuals but with other signal molecules such as kinases, Rac/Rop small GTPases and hormones, mediating a series of signal transmissions. In a similar way, NOX-mediated signaling also participates in abiotic stress response of plants. We summarized here the complex role and regulation mechanism of NOXs in mediating plant immune response, and the viewpoint that abiotic stress response of plants may be a kind of special plant immunity is also proposed.