ID:TGS1_HUMAN DESCRIPTION: RecName: Full=Trimethylguanosine synthase; EC=2.1.1.-; AltName: Full=CLL-associated antigen KW-2; AltName: Full=Cap-specific guanine-N2 methyltransferase; AltName: Full=Hepatocellular carcinoma-associated antigen 137; AltName: Full=Nuclear receptor coactivator 6-interacting protein; AltName: Full=PRIP-interacting protein with methyltransferase motif; Short=PIMT; Short=PIPMT; FUNCTION: Catalyzes the 2 serial methylation steps for the conversion of the 7-monomethylguanosine (m(7)G) caps of snRNAs and snoRNAs to a 2,2,7-trimethylguanosine (m(2,2,7)G) cap structure. The enzyme is specific for guanine, and N7 methylation must precede N2 methylation. Hypermethylation of the m7G cap of U snRNAs leads to their concentration in nuclear foci, their colocalization with coilin and the formation of canonical Cajal bodies (CBs). Plays a role in transcriptional regulation. CATALYTIC ACTIVITY: S-adenosyl-L-methionine + m(7)G(5')pppR-RNA = S-adenosyl-L-homocysteine + m(2,7)G(5')pppR-RNA. CATALYTIC ACTIVITY: S-adenosyl-L-methionine + m(2,7)G(5')pppR-RNA = S-adenosyl-L-homocysteine + m(2,2,7)G(5')pppR-RNA. BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=30 uM for m(7)GDP; KM=5 uM for S-adenosyl-L-methionine; pH dependence: Optimum pH is 8.5-9.5; SUBUNIT: May form homooligomers. Interacts with CREBBP/CBP, EED/WAIT1, EP300/P300, NCOA6/PRIP, PPARBP/PBP and SMN. SUBCELLULAR LOCATION: Cytoplasm. Nucleus, Cajal body. Note=A 90 kDa isoform is found in the nucleus while a 55 kDa isoform is found in the cytoplasm and colocalizes with the tubulin network. TISSUE SPECIFICITY: Ubiquitously expressed. High expression in heart, skeletal muscle, kidney, liver and placenta. SIMILARITY: Belongs to the methyltransferase superfamily. Trimethylguanosine synthase family. SEQUENCE CAUTION: Sequence=AAH11999.1; Type=Erroneous initiation; Note=Translation N-terminally extended; Sequence=BAB15516.1; Type=Erroneous initiation; Note=Translation N-terminally extended;
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 Q96RS0
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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.
US Server
