Abstract
OsRac1 functions as a key regulator of defense signaling in rice. So far, we isolated OsRac1 interacting proteins by affinity chromatography and yeast two-hybrid screen. But, these results only indicated in vitro and direct interaction of these proteins with OsRac1. Therefore, we tried to isolate the native protein complexes. The aim of this study is to reveal the existence of OsRac1 complex in vivo, and study how the composition of OsRac1 complex is altered by elicitor treatment in suspension cell cultures.
Proteins extracted from rice transgenic cultured cells of constitutively active OsRac1 (CA-Rac) and dominant negative-OsRac1 (DN-Rac) were applied to gel filtration. Proteins fractionated by gel filtration were probed for proteins involved in innate immunity by western blotting. So, we found that the CA-Rac complex was composed of a higher molecular weight complex than DN-Rac complex and the OsRac1 complex was composed of a larger complex after elicitor treatment.
