ID:SUV91_HUMAN DESCRIPTION: RecName: Full=Histone-lysine N-methyltransferase SUV39H1; EC=2.1.1.43; AltName: Full=Histone H3-K9 methyltransferase 1; Short=H3-K9-HMTase 1; AltName: Full=Lysine N-methyltransferase 1A; AltName: Full=Position-effect variegation 3-9 homolog; AltName: Full=Suppressor of variegation 3-9 homolog 1; Short=Su(var)3-9 homolog 1; FUNCTION: Histone methyltransferase that specifically trimethylates 'Lys-9' of histone H3 using monomethylated H3 'Lys- 9' as substrate. Also weakly methylates histone H1 (in vitro). H3 'Lys-9' trimethylation represents a specific tag for epigenetic transcriptional repression by recruiting HP1 (CBX1, CBX3 and/or CBX5) proteins to methylated histones. Mainly functions in heterochromatin regions, thereby playing a central role in the establishment of constitutive heterochromatin at pericentric and telomere regions. H3 'Lys-9' trimethylation is also required to direct DNA methylation at pericentric repeats. SUV39H1 is targeted to histone H3 via its interaction with RB1 and is involved in many processes, such as repression of MYOD1-stimulated differentiation, regulation of the control switch for exiting the cell cycle and entering differentiation, repression by the PML-RARA fusion protein, BMP-induced repression, repression of switch recombination to IgA and regulation of telomere length. Component of the eNoSC (energy-dependent nucleolar silencing) complex, a complex that mediates silencing of rDNA in response to intracellular energy status and acts by recruiting histone- modifying enzymes. The eNoSC complex is able to sense the energy status of cell: upon glucose starvation, elevation of NAD(+)/NADP(+) ratio activates SIRT1, leading to histone H3 deacetylation followed by dimethylation of H3 at 'Lys-9' (H3K9me2) by SUV39H1 and the formation of silent chromatin in the rDNA locus. CATALYTIC ACTIVITY: S-adenosyl-L-methionine + L-lysine-[histone] = S-adenosyl-L-homocysteine + N(6)-methyl-L-lysine-[histone]. ENZYME REGULATION: Inhibited by S-adenosyl-L-homocysteine. Negatively regulated by KIAA1967/DBC1. SUBUNIT: Interacts with H3 and H4 histones. Interacts with GFI1B, DNMT3B, CBX1, CBX4, KIAA1967/DBC1, MBD1, RUNX1, RUNX3, MYOD1, SMAD5 and RB1. Interacts with SBF1 through the SET domain. Interacts with HDAC1 and HDAC2 through the N-terminus and associates with the core histone deacetylase complex composed of HDAC1, HDAC2, RBBP4 and RBBP7. Component of the eNoSC complex, composed of SIRT1, SUV39H1 and RRP8. In case of infection, interacts with HTLV-1 Tax protein, leading to abrogate Tax transactivation of HTLV-1 LTR. Interacts (via SET domain) with MECOM; enhances MECOM transcriptional repression activity (By similarity). INTERACTION: P68432:- (xeno); NbExp=2; IntAct=EBI-349968, EBI-79764; P45973:CBX5; NbExp=3; IntAct=EBI-349968, EBI-78219; Q13547:HDAC1; NbExp=3; IntAct=EBI-349968, EBI-301834; Q92769:HDAC2; NbExp=3; IntAct=EBI-349968, EBI-301821; Q9UIS9:MBD1; NbExp=5; IntAct=EBI-349968, EBI-867196; O43159:RRP8; NbExp=3; IntAct=EBI-349968, EBI-2008793; SUBCELLULAR LOCATION: Nucleus. Chromosome, centromere. Note=Associates with centromeric constitutive heterochromatin. DEVELOPMENTAL STAGE: Accumulates during mitosis at centromeres during prometaphase, but dissociates from the centromere at the meta- to anaphase transition. DOMAIN: Although the SET domain contains the active site of enzymatic activity, both pre-SET and post-SET domains are required for methyltransferase activity. The SET domain also participates to stable binding to heterochromatin. PTM: Phosphorylated on serine residues, and to a lesser degree, on threonine residues. The phosphorylated form is stabilized by SBF1 and is less active in its transcriptional repressor function. PTM: Acetylated at Lys-266, leading to inhibition of enzyme activity. SIRT1-mediated deacetylation relieves this inhibition. SIMILARITY: Belongs to the histone-lysine methyltransferase family. Suvar3-9 subfamily. SIMILARITY: Contains 1 chromo domain. SIMILARITY: Contains 1 post-SET domain. SIMILARITY: Contains 1 pre-SET domain. SIMILARITY: Contains 1 SET domain.
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on O43463
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.