Reaction: S-adenosyl-L-methionine + a 5′-(5′-triphosphoguanosine)-[mRNA] = S-adenosyl-L-homocysteine + a 5′-(N7-methyl 5′-triphosphoguanosine)-[mRNA]
Glossary: a 5′-(5′-triphosphoguanosine)-[mRNA] = G5′ppp5’R-[mRNA]
a 5′-(N7-methyl 5′-triphosphoguanosine)-[mRNA] = m7G5′ppp5’R-[mRNA] = cap0
Other name(s): RNMT (gene name); ABD1 (gene name); messenger ribonucleate guanine 7-methyltransferase; guanine-7-methyltransferase; messenger RNA guanine 7-methyltransferase; S-adenosyl-L-methionine:mRNA (guanine-7-N)-methyltransferase
Systematic name: S-adenosyl-L-methionine:mRNA (guanine-N7-)-methyltransferase
Comments: The terminal N7-methylguanosine facilitates gene expression in eukaryotic cells and is recognized by cap-binding proteins.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 56941-25-4
References:
1. Ensinger, M.J., Martin, S.A., Paoletti, E. and Moss, B. Modification of the 5'-terminus of mRNA by soluble guanylyl and methyl transferases from vaccinia virus. Proc. Natl. Acad. Sci. USA 72 (1975) 2525-2529. [PMID: 1058472]
2. Groner, Y., Gilbao, E. and Aviv, H. Methylation and capping of RNA polymerase II primary transcripts by HeLa nuclear homogenates. Biochemistry 17 (1978) 977-982. [PMID: 629955]
3. Martin, S.A. and Moss, B. Modification of RNA by mRNA guanylyltransferase and mRNA (guanine-7)methyltransferase from vaccinia virions. J. Biol. Chem. 250 (1975) 9330-9335. [PMID: 76069264]
4. Martin, S.A., Paoletti, E. and Moss, B. Purification of mRNA guanylyltransferase and mRNA (guanine-7-) methyltransferase from vaccinia virions. J. Biol. Chem. 250 (1975) 9322-9329. [PMID: 1194287]
5. Mao, X., Schwer, B. and Shuman, S. Yeast mRNA cap methyltransferase is a 50-kilodalton protein encoded by an essential gene. Mol. Cell Biol. 15 (1995) 4167–4174. [PMID: 7623811]
6. Pillutla, R.C., Yue, Z., Maldonado, E. and Shatkin, A.J. Recombinant human mRNA cap methyltransferase binds capping enzyme/RNA polymerase IIo complexes. J. Biol. Chem. 273 (1998) 21443–21446. [PMID: 9705270]
7. Tsukamoto, T., Shibagaki, Y., Niikura, Y. and Mizumoto, K. Cloning and characterization of three human cDNAs encoding mRNA (guanine-7-)-methyltransferase, an mRNA cap methylase. Biochem. Biophys. Res. Commun. 251 (1998) 27–34. [PMID: 9790902]