Abstract
Results of recent studies on cytokinin responses in Arabidopsis thaliana, a His-Asp phosphorelay was revealed to play an essential role in the primary responses of plants to cytokinin. It is assumed that the downstream cytokinin-responsive signaling network must be very diverse and complicated. To gain insight into the downstream signaling network, we previously conducted a genome-wide DNA microarray analysis, which allowed us to identify a number of cytokinin-inducible genes. Amongst them, here we focused on a few such genes, and they were intensively characterized through both forward and reverse genetics. They included: (1) ASL9 (At1g16530) encoding a member of the AS2 (ASYMMETRIC 2) family, (2) CGA1 (At4g26150) encoding a light-responsive GATA-type transcription factor, (3) RADI1 (At2g21650) encoding a protein with a single SANT/MYB domain. The results will be summarized with special reference to possible links between these cytokinin-responsive genes and the cytokinin-mediated signal transduction in plants.
