Expanded lysine acetylation specificity of Gcn5 in native complexes.
The coactivator/adaptor protein Gcn5 is a conserved histone acetyltransferase, which functions as the catalytic subunit in multiple yeast transcriptional regulatory complexes. The ability of Gcn5 to acetylate nucleosomal histones is significantly reduced relative to its activity on free histones, where it predominantly modifies histone H3 at lysine 14. However, the association of Gcn5 in multisubunit complexes potentiates its nucleosomal histone acetyltransferase activity. Here, we show that the association of Gcn5 with other proteins in two native yeast complexes, Ada and SAGA (Spt-Ada-Gcn5-acetyltransferase), directly confers upon Gcn5 the ability to acetylate an expanded set of lysines on H3. Furthermore Ada and SAGA have overlapping, yet distinct, patterns of acetylation, suggesting that the association of specific subunits determines site specificity.
Pubmed ID: 10026213 RIS Download
Acetylation | Acetyltransferases | Amino Acid Sequence | DNA-Binding Proteins | Fungal Proteins | Histone Acetyltransferases | Lysine | Molecular Sequence Data | Protein Kinases | Saccharomyces cerevisiae Proteins | Substrate Specificity