Studi funzionali del fattore trascrizionale DcE2F diDaucus carotatramite sovraespressione in piantine transgeniche diArabidopsis thaliana

The E2F transcription factors are key components of the RB/E2F pathway which controls the G1/S transition of the cell cycle and is conserved in animals and plants. The E2Fs can be divided into different classes which have been shown to act as activators or repressors of E2F-dependent genes. Moreover, plant and animal E2Fs are known to regulate other cellular functions in addition to cell cycle progression. In this study we describe the effects of over-expressing in Arabidopsis the DcE2F factor from carrot (Daucus carota), one of the first plant E2F factors to be isolated and characterized. DcE2F transactivates a reporter gene in transient assays, but the functional role of this proteinin plantawas not defined. Here we show that the over-expression of DcE2F in transgenic Arabidopsis plants causes effects that are similar to those observed when over-expressing the activating AtE2F proteins (AtE2Fa or AtE2Fb) ofArabidopsis thaliana. These results indicate that DcE2F can promote cell proliferation and can modify embryo and plant development, but also reveal some new aspects about the activating E2Fs of Arabidopsis.