Abstract
RIM1 (rice dwarf virus multiplication1), which is identified as a host factor involved in RDV multiplication, encoded a novel NAC transcription factor of rice. To know the function of the RIM1, we identified loss-of-function mutants from the Tos17 mutant panel. The rim1 mutations showed the phenotype of root growth inhibition, which was similar to the phenotype induced by jasmonic acid (JA) treatment in WT. Microarray analysis revealed mutant's expression profile is significantly correlated with the profile of JA-treated WT, indicating JA-responsible genes are constitutively expressed in the rim1 mutant. To know if the rim1 mutation affects endogenous JA accumulation or not, we measured the JA level under normal condition. The level of JA in the mutant is similar to that in WT, implying that the rim1 mutation is not involved in JA biosynthesis but in JA signaling. These results indicate RIM1 acts as a negative regulator in JA signaling pathway.
