2rpq
From Proteopedia
Solution Structure of a SUMO-interacting motif of MBD1-containing chromatin-associated factor 1 bound to SUMO-3
Structural highlights
Function[SUMO2_HUMAN] Ubiquitin-like protein that can be covalently attached to proteins as a monomer or as a lysine-linked polymer. Covalent attachment via an isopeptide bond to its substrates requires prior activation by the E1 complex SAE1-SAE2 and linkage to the E2 enzyme UBE2I, and can be promoted by an E3 ligase such as PIAS1-4, RANBP2 or CBX4. This post-translational modification on lysine residues of proteins plays a crucial role in a number of cellular processes such as nuclear transport, DNA replication and repair, mitosis and signal transduction. Polymeric SUMO2 chains are also susceptible to polyubiquitination which functions as a signal for proteasomal degradation of modified proteins.[1] [2] [3] [MCAF1_HUMAN] Recruiter that couples transcriptional factors to general transcription apparatus and thereby modulates transcription regulation and chromatin formation. Can both act as an activator or a repressor depending on the context. Mediates MBD1-dependent transcriptional repression, probably by recruiting complexes containing SETDB1. Required to stimulate histone methyltransferase activity of SETDB1 and facilitate the conversion of dimethylated to trimethylated H3 'Lys-9' (H3K9me3). The complex formed with MBD1 and SETDB1 represses transcription and couples DNA methylation and histone H3 'Lys-9' trimethylation (H3K9me3). Facilitates telomerase TERT and TERC gene expression by SP1 in cancer cells.[4] [5] [6] 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 PubMedPost-translational modification by small ubiquitin-like modifier (SUMO) proteins has been implicated in the regulation of a variety of cellular events. The functions of sumoylation are often mediated by downstream effector proteins harboring SUMO-interacting motifs (SIMs) that are composed of a hydrophobic core and a stretch of acidic residues. MBD1-containing chromatin-associated factor 1 (MCAF1), a transcription repressor, interacts with SUMO-2/3 and SUMO-1, with a preference for SUMO-2/3. We used NMR spectroscopy to solve the solution structure of the SIM of MCAF1 bound to SUMO-3. The hydrophobic core of the SIM forms a parallel beta-sheet pairing with strand beta2 of SUMO-3, whereas its C-terminal acidic stretch seems to mediate electrostatic interactions with a surface area formed by basic residues of SUMO-3. The significance of these electrostatic interactions was shown by mutations of both SUMO-3 and MCAF1. The present structural and biochemical data suggest that the acidic stretch of the SIM of MCAF1 plays an important role in the binding to SUMO-3. Structure of the small ubiquitin-like modifier (SUMO)-interacting motif of MBD1-containing chromatin-associated factor 1 bound to SUMO-3.,Sekiyama N, Ikegami T, Yamane T, Ikeguchi M, Uchimura Y, Baba D, Ariyoshi M, Tochio H, Saitoh H, Shirakawa M J Biol Chem. 2008 Dec 19;283(51):35966-75. Epub 2008 Oct 7. PMID:18842587[7] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Human | Ariyoshi, M | Baba, D | Ikegami, T | Ikeguchi, M | Saitoh, H | Sekiyama, N | Shirakawa, M | Tochio, H | Uchimura, Y | Yamane, T | Activator | Host-virus interaction | Nucleus | Phosphoprotein | Repressor | Sim | Sumo | Transcription | Transcription regulation | Ubl conjugation pathway
