Editors' ChoiceTranscription factors

E2F, Et Tu p300?

Science's STKE  18 Apr 2000:
Vol. 2000, Issue 28, pp. tw6
DOI: 10.1126/stke.2000.28.tw6

Acetylation of histone proteins by cellular acetyltransferases leads to increased accessibility of chromatin to transcription factors. Some transcription factors are also acetylated by the same acetyltransferases. Marzio et al. studied the ability of the histone acetyltransferases p300 and CBP to acetylate the six members of the E2F transcription factor family. Only E2F-1, E2F-2, and E2F-3 were acetylated by acetyltransferases in nuclear lysates. Similarly, only these three E2F isoforms were coprecipitated with p300 in vitro. An E2F-1 mutant that cannot be acetylated could still bind to p300 in vitro, which indicated that: (i) certain motifs found in E2F-1, E2F-2, and E2F-3 but not found in the other isoforms were responsible for binding p300, and (ii) the binding of E2F isoforms to p300 was stable in the absence of sites for acetylation. In addition, acetylated E2F-1, as compared with unacetylated E2F, appeared to increase its affinity for specific DNA sequences and led to increased expression of luciferase through an E2F-responsive promoter.

Marzio, G., Wagener, C., Gutierrez, M.I., Cartwright, P., Helin, K., and Giacca, M. (2000) E2F family members are differentially regulated by reversible acetylation. J. Biol. Chem. 275: 10887-10892. [Abstract] [Full Text]