Functional similarity and physical association between GCN5 and ADA2: putative transcriptional adaptors.

AUTOR(ES)

Marcus, G A

RESUMO

A selection for yeast mutants resistant to GAL4-VP16-induced toxicity previously identified two genes, ADA2 and ADA3, which may function as adaptors for some transcriptional activation domains and thereby facilitate activation. Here we identify two new genes by the same selection, one of which is identical to GCN5. We show that gcn5 mutants share properties with ada mutants, including slow growth, temperature sensitivity and reduced activation by the VP16 and GCN4 activation domains. Double mutant studies suggest that ADA2 and GCN5 function together in a complex or pathway. Moreover, we demonstrate that GCN5 binds to ADA2 both by the two-hybrid assay in vivo and by co-immunoprecipitation in vitro. This suggests that ADA2 and GCN5 are part of a heteromeric complex that mediates transcriptional activation. Finally, we demonstrate the functional importance of the bromodomain of GCN5, a sequence found in other global transcription factors such as the SWI/SNF complex and the TATA binding protein-associated factors. This domain is not required for the interaction between GCN5 and ADA2 and thus may mediate a more general activity of transcription factors.

Documentos Relacionados

• ADA3, a putative transcriptional adaptor, consists of two separable domains and interacts with ADA2 and GCN5 in a trimeric complex.
• Identification of human proteins functionally conserved with the yeast putative adaptors ADA2 and GCN5.
• Disruption Mutations of ADA2b and GCN5 Transcriptional Adaptor Genes Dramatically Affect Arabidopsis Growth, Development, and Gene ExpressionW⃞
• Two Different Drosophila ADA2 Homologues Are Present in Distinct GCN5 Histone Acetyltransferase-Containing Complexes
• A Novel Human Ada2 Homologue Functions with Gcn5 or Brg1 To Coactivate Transcription