Abstract
Plants have developed various mechanisms to grow even in the presence of pathogens. Our previous research using uni-1D mutant, a constitutively active mutant of a CC-NB-LRR gene, suggests a unique possibility that plants change morphology for protection against pathogens. However molecular mechanisms for this phenomenon are unknown.
uni-1D mutant has 3 major phenotypes; up-regulation of PR1/5 expression (an aspect of pathogenesis responses), ectopic axillary meristem formation and defect of meristem maintenance. We first analyzed uni-1D morphological phenotypes in meristem-related mutants and also promoter-GUS activities of meristem-related genes in uni-1D mutant. Further we isolated suppressor mutants of uni-1D morphological abnormalities and analyzed them. From these experiments, distinct mechanisms regulating each uni-1D phenotype were implied. Interestingly, some suppressor mutants have meristem-related phenotypes without uni-1D mutant allele, suggesting that the mechanisms which are affected by uni-1D have roles in meristem regulation even in wild-type background.
