Structural highlights
Function
[SIN3B_MOUSE] Acts as a transcriptional repressor. Interacts with MXI1 to repress MYC responsive genes and antagonize MYC oncogenic activities. Interacts with MAD-MAX heterodimers by binding to MAD. The heterodimer then represses transcription by tethering SIN3B to DNA. Also forms a complex with FOXK1 which represses transcription.[1] [2] [MAD1_HUMAN] Transcriptional repressor. MAD binds with MAX to form a sequence-specific DNA-binding protein complex which recognizes the core sequence 5'-CAC[GA]TG-3'. MAD thus antagonizes MYC transcriptional activity by competing for MAX.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Sin3 forms the scaffold for a multiprotein corepressor complex that silences transcription via the action of histone deacetylases. Sin3 is recruited to the DNA by several DNA binding repressors, such as the helix-loop-helix proteins of the Mad family. Here, we elaborate on the Mad-Sin3 interaction based on a binding study, solution structure, and dynamics of the PAH2 domain of mSin3 in complex to an extended Sin3 interacting domain (SID) of 24 residues of Mad1. We show that SID residues Met7 and Glu23, outside the previously defined minimal binding motif, mediate additional hydrophobic and electrostatic interactions with PAH2. On the basis of these results we propose an extended consensus sequence describing the PAH2-SID interaction specifically for the Mad family, showing that residues outside the hydrophobic core of the SID interact with PAH2 and modulate binding affinity to appropriate levels.
Extension of the binding motif of the Sin3 interacting domain of the Mad family proteins.,van Ingen H, Lasonder E, Jansen JF, Kaan AM, Spronk CA, Stunnenberg HG, Vuister GW Biochemistry. 2004 Jan 13;43(1):46-54. PMID:14705930[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Ayer DE, Lawrence QA, Eisenman RN. Mad-Max transcriptional repression is mediated by ternary complex formation with mammalian homologs of yeast repressor Sin3. Cell. 1995 Mar 10;80(5):767-76. PMID:7889570
- ↑ Yang Q, Kong Y, Rothermel B, Garry DJ, Bassel-Duby R, Williams RS. The winged-helix/forkhead protein myocyte nuclear factor beta (MNF-beta) forms a co-repressor complex with mammalian sin3B. Biochem J. 2000 Jan 15;345 Pt 2:335-43. PMID:10620510
- ↑ van Ingen H, Lasonder E, Jansen JF, Kaan AM, Spronk CA, Stunnenberg HG, Vuister GW. Extension of the binding motif of the Sin3 interacting domain of the Mad family proteins. Biochemistry. 2004 Jan 13;43(1):46-54. PMID:14705930 doi:http://dx.doi.org/10.1021/bi0355645
