Molecular signaling in disease resistance of rice
We thank Megumi Iwano, Hikaru Satoh, Katsuhiko Shii, Morifumi Hasegawa, and Osamu Kodama for collaboration and Kenji Henmi, Eiichiro Ono, Hann Ling Wong, and Satoru Hatakeyama for various contributions to the work described here. We also thank members of the Plant Molecular Genetics Lab at NAIST for numerous suggestions.
We study signaling pathways involved in the interaction of rice and the rice blast fungus, Magnaporthe grisea, by using molecular and genetic methods. We recently demonstrated that the rice homologue of the small GTPase Rac is an important molecular switch for resistance gene–mediated disease resistance against rice blast infection. Furthermore, it was shown to activate the production of reactive oxygen species as well as cell death, both of which are often observed during the resistance response to avirulent pathogens in many plant systems. In another approach, we study lesion-mimic mutants of rice showing increased resistance to the rice blast fungus. Biochemical analysis of these mutants allowed us to identify genes that may play an important role in disease resistance of rice.
