Abstract
RSG is a transcriptional activator, which regulates shoot growth by controlling endogenous level of gibberellins. Overexpression of dominant-negative mutant of RSG resulted in severe dwarfism. To understanding networking of RSG, we sought RSG-interacting proteins and succeeded in isolation of some cDNAs by tow-hybrid screen. One of them coded 14-3-3 proteins, which are conserved regulatory factors among eukaryote and known to regulate function of the target through binding to phosphorylated serine residue in it. Until now, 14-3-3 protein has revealed to regulate negatively RSG by sequester it in cytoplasm through binding with phosphorylated serine-114 of RSG. Furthermore, it has exhibited that RSG was not statically resided in cytoplasm but dynamically shuttling between nucleus and cytoplasm, by treatment of Leptomycin B that specifically inhibits nuclear export receptor Exportin1 . With the aim of fully understanding of significance of regulation of RSG by 14-3-3, we examine a signal which controls intracellularlocalization of RSG.
