GCN5related

GCN5-related refers to the GCN5-related N-acetyltransferase (GNAT) superfamily, a broad and evolutionarily widespread group of enzymes that catalyze the transfer of acetyl groups from acetyl-CoA to various substrates. The family is named after GCN5, a histone acetyltransferase in the yeast Saccharomyces cerevisiae, and encompasses many enzymes with diverse biological roles across life forms.

In eukaryotes, members such as GCN5 and PCAF (p300/CBP-associated factor) function as histone acetyltransferases that participate in transcriptional activation. They are components of larger coactivator assemblies, including SAGA and ATAC complexes, where they acetylate histone lysines to promote open chromatin and gene expression. Beyond histones, GNAT enzymes also target non-histone proteins and a variety of small molecules, contributing to regulatory networks in metabolism, signaling, and chromatin dynamics.

In prokaryotes and archaea, GNATs include aminoglycoside N-acetyltransferases and related enzymes that modify diverse substrates. These activities can influence antibiotic resistance, metabolic regulation, and other cellular processes. The structural hallmark of GNATs is a conserved acetyl-CoA-dependent catalytic core, with substrate specificity shaped by surrounding residues and domain organization. The GNAT domain is found as a standalone module or fused within larger proteins, reflecting functional diversity.

Overall, the GCN5-related family represents a versatile and widely distributed class of acetyltransferases that shares a common acetyl-transfer mechanism while mediating a broad range of biological functions. See also GNAT superfamily, GCN5, and PCAF.