Characterization of two distinct DP-related genes from Arabidopsis thaliana

E2F/DP complexes play a pivotal role in the regulation of the G1/S transiti on in animals, Recently, plant E2F homologs have been cloned, but DP-relate d sequences have not been identified so far. Here we report that Arabidopsi s thaliana contains at least two different DP-related genes, AtDPa and AtDP b, They exhibit an overall domain organization similar to that of their ani mal counterparts, although phylogenetic analysis demonstrated that they for m a separate subgroup. AtDPs efficiently heterodimerize in vitro with the A rabidopsis E2F-related proteins, AtE2Fa and AtE2Fb through their dimerizati on domains. AtDPa and AtE2Fa are predominantly produced in actively dividin g cells with highest transcript levels in early S phase cells. (C) 2000 Fed eration of European Biochemical Societies. Published by Elsevier Science B, V. All rights reserved.