Sin3A corepressor complex (Sin3A complex)

The Sin3A corepressor complex is a multi-subunit protein assembly that serves as a critical scaffold for chromatin-modifying enzymes, primarily histone deacetylases 1 and 2 (HDAC1/2) (UniProt Q96ST3). It functions as a central node in transcriptional regulation, mediating gene silencing by deacetylating histone tails, which promotes a condensed, transcriptionally inactive chromatin structure (PubMed: 25635340). The complex is recruited to specific DNA sites by various transcription factors, including the Mad family, p53, and several nuclear receptors, thereby regulating essential cellular processes such as the cell cycle, differentiation, and apoptosis (PubMed: 30104615). In oncology, the Sin3A complex is frequently hijacked to repress tumor suppressor genes and promote the epithelial-mesenchymal transition (EMT), contributing to metastasis and chemoresistance in breast, lung, and colon cancers (PubMed: 22810394). Therapeutic targeting of the complex involves two main strategies: the use of HDAC inhibitors to block enzymatic activity and the development of small molecules or peptidomimetics designed to disrupt the Sin3-interactor domain (SID) to prevent the recruitment of the complex to oncogenic targets (PubMed: 26166218). While promising, targeting this complex poses significant challenges due to its broad role in normal cellular homeostasis and the potential for systemic toxicity resulting from widespread epigenetic changes (PubMed: 28841414).

Other names

SIN3A-HDAC complexSIN3-HDAC complexSin3 transcription regulator homolog A complexSIN3A complexHistone deacetylase-Sin3A complex

Inhibition of histone deacetylase (HDAC) enzymatic activity within the complex or disruption of protein-protein interactions between Sin3A and its recruitment partners via Sin3-interactor domain (SID) antagonism.