Yng2

Yng2 is a protein encoded by the YNG2 gene in the budding yeast Saccharomyces cerevisiae. It serves as a non-catalytic subunit of the NuA4 histone acetyltransferase (HAT) complex, a multi-subunit machine that modifies chromatin to regulate transcription and DNA repair. In this context, Yng2 helps assemble the complex and contributes to its targeting to chromatin, supporting the acetylation of histones H4 and H2A.

Protein features and interactions: Yng2 is believed to contain domains that facilitate chromatin association, including a region known to participate in recognizing histone marks. It participates in interactions with other NuA4 components, notably the Esa1 catalytic subunit and partners such as Eaf1 and Yaf9, helping recruit the HAT activity to nucleosomes and promote histone acetylation.

Genetic and cellular effects: Loss or disruption of YNG2 leads to reduced histone acetylation and broad changes in gene expression. Phenotypically, YNG2 mutants can exhibit growth defects, altered transcriptional responses, and increased sensitivity to DNA damaging agents, reflecting the role of NuA4-mediated acetylation in chromatin regulation and genome stability.

Evolution and nomenclature: YNG2 is conserved among fungal species and is considered a core component of the NuA4 complex in yeast. In higher eukaryotes, analogous chromatin-modifying complexes exist (such as TIP60), underscoring the conserved link between histone acetylation, transcriptional control, and DNA repair across species.