2rpq

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.

See Also

• SUMO

References

1. ↑ Kamitani T, Kito K, Nguyen HP, Fukuda-Kamitani T, Yeh ET. Characterization of a second member of the sentrin family of ubiquitin-like proteins. J Biol Chem. 1998 May 1;273(18):11349-53. PMID:9556629
2. ↑ Meulmeester E, Kunze M, Hsiao HH, Urlaub H, Melchior F. Mechanism and consequences for paralog-specific sumoylation of ubiquitin-specific protease 25. Mol Cell. 2008 Jun 6;30(5):610-9. doi: 10.1016/j.molcel.2008.03.021. PMID:18538659 doi:10.1016/j.molcel.2008.03.021
3. ↑ Tatham MH, Geoffroy MC, Shen L, Plechanovova A, Hattersley N, Jaffray EG, Palvimo JJ, Hay RT. RNF4 is a poly-SUMO-specific E3 ubiquitin ligase required for arsenic-induced PML degradation. Nat Cell Biol. 2008 May;10(5):538-46. doi: 10.1038/ncb1716. Epub 2008 Apr 13. PMID:18408734 doi:10.1038/ncb1716
4. ↑ Wang H, An W, Cao R, Xia L, Erdjument-Bromage H, Chatton B, Tempst P, Roeder RG, Zhang Y. mAM facilitates conversion by ESET of dimethyl to trimethyl lysine 9 of histone H3 to cause transcriptional repression. Mol Cell. 2003 Aug;12(2):475-87. PMID:14536086
5. ↑ Fujita N, Watanabe S, Ichimura T, Ohkuma Y, Chiba T, Saya H, Nakao M. MCAF mediates MBD1-dependent transcriptional repression. Mol Cell Biol. 2003 Apr;23(8):2834-43. PMID:12665582
6. ↑ Liu L, Ishihara K, Ichimura T, Fujita N, Hino S, Tomita S, Watanabe S, Saitoh N, Ito T, Nakao M. MCAF1/AM is involved in Sp1-mediated maintenance of cancer-associated telomerase activity. J Biol Chem. 2009 Feb 20;284(8):5165-74. doi: 10.1074/jbc.M807098200. Epub 2008, Dec 23. PMID:19106100 doi:http://dx.doi.org/10.1074/jbc.M807098200