Transcriptional regulatory protein Sin3-like (IPR039774)

Short name: Sin3-like

Overlapping homologous superfamilies

Family relationships


Proteins in this entry contain N-terminal PAH (paired amphipathic helix) repeats, a histone deacetylase interacting domain, and a Sin3, C-terminal domain. Sin3 proteins have at least three PAH domains (PAH1, PAH2, and PAH3). They are components of a co-repressor complex that silences transcription, playing important roles in the transition between proliferation and differentiation. Sin3 proteins are recruited to the DNA by various DNA-binding transcription factors such as the Mad family of repressors, Mnt/Rox, PLZF, MeCP2, p53, REST/NRSF, MNFbeta, Sp1, TGIF and Ume6 [PMID: 11101889]. Sin3 acts as a scaffold protein that in turn recruits histone-binding proteins RbAp46/RbAp48 and histone deacetylases HDAC1/HDAC2, which deacetylate the core histones resulting in a repressed state of the chromatin [PMID: 14705930]. The PAH domains are protein-protein interaction domains through which Sin3 fulfils its role as a scaffold. The PAH2 domain of Sin3 can interact with a wide range of unrelated and structurally diverse transcription factors that bind using different interaction motifs. For example, the Sin3 PAH2 domain can interact with the unrelated Mad and HBP1 factors using alternative interaction motifs that involve binding in opposite helical orientations [PMID: 15235594]. The Sin3, C-terminal domain forms interactions with histone deacetylases [PMID: 12773392].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0003714 transcription corepressor activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.