抄録
Rar1 is a CHORD-containing gene and essential for Rgene-mediated resistance in plants. In addition to Rar1, small GTPase Rac family was also found to play an important role in disease resistance in rice. Immunoprecipitation (IP) assay indicated that OsRac1 and Rar1 existed in the same complex. To study the function and relationship between OsRac1 and OsRar1 in rice disease resistance we used OsRac1-RNAi and CA-OsRac1 transgenic plants for genetic analysis. Results of plant infection assays suggest that OsRar1 contributes to basal resistance, whereas lack of OsRar1did not alter Pi-a, Pi-b and Pi-z mediated resistance. OsRac1 and OsRar1 may function in parallel pathways, OsRar1 silencing impairs the basal resistance, however overexpressing CA-OsRac1 can compensate the loss of OsRar1 function. Yeast two hybrid assay indicated that OsRar1, OsSgt1 and HSP90 may form a scaffold of a big complex. OsRac1 may exist in this complex but not directly associate with the scaffold.
