Molecular Analysis of the E2F/DP Gene Family of Daucus carota and Involvement of the DcE2F1 Factor in Cell Proliferation

E2F transcription factors are key components of the RB/E2F pathway that, through action cyclin-dependent kinases, regulates cell cycle progression in both plants and animals. Moreover, plant animal E2Fs have also been shown to regulate other cellular functions addition proliferation. Based on structural functional features, they can be divided into different classes that act as activators or repressors E2F-dependent genes. Among first reported, we previously described DcE2F1, an activating which is expressed cycling carrot ( Daucus carota ) cells. In this study, describe identification additional members E2F/DP family D. , includes four typical E2Fs, three atypical E2F/DEL genes, related DP Expression analyses genes reveal distinctive patterns suggest some them not necessarily linked DcE2F1 was transactivate E2F-responsive promoter transient assays but role protein planta defined. Sequence comparisons indicate could ortholog AtE2FA factor Arabidopsis thaliana . ectopic expression cDNA transgenic able upregulate AtE2FB promotes proliferation, giving rise polycotyly with low frequency, effects highly similar those observed when over-expressing These results involved control proliferation plays important roles regulation embryo development.