Sin3 histone deacetylase corepressor complex component SDS3 (SUDS3)

Sin3 histone deacetylase corepressor complex component SDS3 (SUDS3) is a conserved protein subunit incorporated into the Sin3A/HDAC corepressor complex. It stabilizes the complex and facilitates its assembly through direct protein-protein interactions, particularly with the Sin3A scaffolding protein via a defined helix interaction domain. SUDS3 itself is not an enzyme but acts as a structural organizer, helping recruit Class I HDACs (HDAC1/2) essential for chromatin remodeling, gene silencing, and transcriptional regulation. These complexes are vital for cell fate decisions, neural development, cancer progression, and maintenance of stem cell identity. SUDS3 is thus an important regulatory factor in coordinating epigenetic gene expression, and its disruption is linked to developmental and oncogenic pathologies.

Other names

SUDS3SAP45SDS3FLJ0005245 kDa Sin3-associated polypeptideSuppressor of defective silencing 3 protein homologSin3A-associated protein, 45 kDaSDS3 homologSin3A corepressor complex component

HDAC inhibitors block the histone deacetylase enzymatic activity in the Sin3A complex, leading to increased acetylation, chromatin relaxation, and upregulation of previously silenced genes. SUDS3 itself does not possess HDAC activity but is essential for the structural integrity and recruitment of HDACs to the complex.