Eaf3s

Eaf3s refers to a family of chromatin-associated proteins encoded by EAF3 genes in diverse eukaryotes. They are best known for their involvement in histone-modifying enzyme complexes and are especially characterized in fungi, where a canonical Eaf3 protein is a subunit of the NuA4 histone acetyltransferase complex. Eaf3 proteins typically contain a chromodomain, a module that can recognize methylated lysine residues on histone tails, enabling the complex to associate with transcriptionally active regions of chromatin.

Functions of Eaf3s center on linking histone methylation marks to acetylation and transcription regulation. In yeast, Eaf3 contributes to the targeted recruitment of acetyltransferase activity to gene bodies and promoters, helping to coordinate chromatin state with transcription. Eaf3 homologs are found in other fungi and in some metazoans, where they participate in analogous chromatin-modifying assemblies. The precise composition of Eaf3-containing complexes and their biological roles can vary by species and cellular context, and Eaf3s often interact with other chromatin remodelers and transcription factors.

Evolutionarily, Eaf3 proteins are conserved across fungi, with occasional gene duplications giving rise to paralogs in some lineages. Comparative studies of Eaf3s help illuminate the diversification of chromatin-related regulatory networks. While sharing a common name and domain architecture, Eaf3s in different organisms can differ in sequence and in the exact partners of the complexes they join, reflecting adaptation to species-specific transcriptional programs.