ADA1, a novel component of the ADA/GCN5 complex, has broader effects than GCN5, ADA2, or ADA3.

AUTOR(ES)

Horiuchi, J

RESUMO

The ADA genes encode factors which are proposed to function as transcriptional coactivators. Here we describe the cloning, sequencing, and initial characterization of a novel ADA gene, ADA1. Similar to the previously isolated ada mutants, ada1 mutants display decreases in transcription from various reporters. Furthermore, ADA1 interacts with the other ADAs in the ADA/GCN5 complex as demonstrated by partial purification of the complex and immunoprecipitation experiments. We estimate that the complex has a molecular mass of approximately 2 MDa. Previously, it had been demonstrated that ada5 mutants displayed more severe phenotypic defects than the other ada mutants (G. A. Marcus, J. Horiuchi, N. Silverman, and L. Guarente, Mol. Cell. Biol. 16:3197-3205, 1996; S. M. Roberts and F. Winston, Mol. Cell. Biol. 16:3206-3213, 1996). ada1 mutants display defects similar to those of ada5 mutants and different from those of the other mutants with respect to promoters affected, inositol auxotrophy, and Spt- phenotypes. Thus, the ADAs can be separated into two classes, suggesting that the ADA/GCN5 complex may have two separate functions. We present a speculative model on the possible roles of the ADA/GCN5 complex.

Documentos Relacionados

• Role for ADA/GCN5 products in antagonizing chromatin-mediated transcriptional repression.
• A Novel Human Ada2 Homologue Functions with Gcn5 or Brg1 To Coactivate Transcription
• ADA3, a putative transcriptional adaptor, consists of two separable domains and interacts with ADA2 and GCN5 in a trimeric complex.
• Nse1, Nse2, and a Novel Subunit of the Smc5-Smc6 Complex, Nse3, Play a Crucial Role in Meiosis
• Role for Nhp6, Gcn5, and the Swi/Snf Complex in Stimulating Formation of the TATA-Binding Protein-TFIIA-DNA Complex