Abstract
Auxin promotes lateral root (LR) formation in higher plants. The solitary-root (slr) mutants in Arabidopsis, which have gain-of-function mutations in IAA14, a member of Aux/IAA family, have no LRs. It is suggested that the mutant IAA14 protein might repress the activity of Auxin Response Factors (ARFs), which promote LR formation, through the interaction with them. In this symposium, we will discuss two topics, 1) Roles of Aux/IAAs and ARFs in LR formation, and 2) Involvement of chromatin remodeling in LR formation. Now we are studying two ARFs required for LR formation. The data on the roles of these ARFs and SLR/IAA14 in LR formation will be presented. Second, we recently isolated the SSL2 (SUPPRESSOR OF SLR 2) gene required for the slr phenotype in LR formation. The SSL2 encodes one of the chromatin remodeling factors. Recent results on functional analysis of SSL2 will be presented.
