AtE2F-a and AtDP-a, members of the E2F family of transcription factors, induce Arabidopsis leaf cells to re-enter S phase.
In eukaryotes, transcription factors of the E2F family, in addition to having a role in cell proliferation, participate in regulating apoptosis, differentiation and development. In Arabidopsis thaliana, eight gene sequences have been identified as encoding E2F or DP homologues. DP proteins form heterodimers with E2Fs. The aim of this work was to characterize the functions of three of these factors: AtE2F-a, AtE2F-b and AtDP-a. Here we report that AtE2F-a and AtE2F-b transactivate a reporter gene via an E2F consensus cis-acting element in Arabidopsis protoplasts. AtE2F-a is a more potent activator than AtE2F-b. Furthermore, co-expression of the E2F partner AtDP-a, or the DNA binding protein AtPur alpha, modulates the activation of AtE2F-a. Taken together, these results suggest that AtE2F-a, AtE2F-b and AtDP-a share features characteristic of members of the E2F family of transcription factors. Moreover, over-expression of AtE2F-a and AtDP-a can induce differentiated, non-dividing, leaf cells to re-enter S-phase. We conclude that the transcription factor AtE2F-a plays an important role in progression into S phase, which probably correlates with its capacity to stimulate transcription.
Rossignol
P
P
Activation et Inhibition du Cycle Cellulaire au cours du Développement, Institut de Biotechnologie des Plantes, CNRS UMR 8618, Université de Paris-Sud, 91405 Orsay, France.
Stevens
R
R
Perennes
C
C
Jasinski
S
S
Cella
R
R
Tremousaygue
D
D
Bergounioux
C
C
D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology*; D018797:Cell Cycle Proteins; D017362:Cyclic AMP Response Element-Binding Protein / Q000235:genetics / Q000502:physiology; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D018515:Plant Leaves / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D020033:Protein Isoforms / Q000235:genetics / Q000502:physiology; D011523:Protoplasts / Q000166:cytology / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016196:S Phase / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D015533:Transcriptional Activation
D029681:Arabidopsis Proteins; D018797:Cell Cycle Proteins; D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D020033:Protein Isoforms; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D005966:Glucuronidase