MRNA (guanine-N7-)-methyltransferase explained

mRNA (guanine-N7-)-methyltransferase
Ec Number:	2.1.1.56
Cas Number:	56941-25-4
Go Code:	0004482

In enzymology, a mRNA (guanine-N7-)-methyltransferase also known as mRNA cap guanine-N7 methyltransferase is an enzyme that catalyzes the chemical reaction

S-adenosyl-L-methionine + G(5')pppR-RNA

\rightleftharpoons S-adenosyl-L-homocysteine + m₇G(5')pppR-RNA (mRNA containing an N⁷-methylguanine cap)

Thus, the two substrates of this enzyme are S-adenosyl methionine and G(5')pppR-RNA, whereas its two products are S-adenosylhomocysteine and m7G(5')pppR-RNA. This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases.

In humans, mRNA cap guanine-N7 methyltransferase is encoded by the RNMT gene.^{[1] [2] [3]}

Nomenclature

The systematic name of this enzyme class is S-adenosyl-L-methionine:mRNA (guanine-N7-)-methyltransferase. Other names in common use include:

• messenger ribonucleate guanine 7-methyltransferase,
• guanine-7-methyltransferase,
• messenger RNA guanine 7-methyltransferase, and
• S-adenosyl-L-methionine:mRNA (guanine-7-N-)-methyltransferase.
• cap MTase

See also

• 7-Methylguanosine

Further reading

• Ensinger MJ, Martin SA, Paoletti E, Moss B . 1975 . Modification of the 5'-terminus of mRNA by soluble guanylyl and methyl transferases from vaccinia virus . Proc. Natl. Acad. Sci. U.S.A. . 72 . 2525 - 9 . 1058472 . 10.1073/pnas.72.7.2525 . 7 . 432801 . 1975PNAS...72.2525E . free .
• Groner Y, Gilboa E, Aviv H . 1978 . Methylation and capping of RNA polymerase II primary transcripts by HeLa nuclear homogenates . Biochemistry . 17 . 977 - 82 . 629955 . 10.1021/bi00599a005 . 6 .
• Martin SA, Moss B . 1975 . Modification of RNA by mRNA guanylyltransferase and mRNA (guanine-7-)methyltransferase from vaccinia virions . J. Biol. Chem. . 250 . 9330 - 5 . 1194287 . 24 . 10.1016/S0021-9258(19)40647-9 . free .
• Martin SA, Paoletti E, Moss B . 1975 . Purification of mRNA guanylyltransferase and mRNA (guanine-7-) methyltransferase from vaccinia virions . J. Biol. Chem. . 250 . 9322 - 9 . 1194286 . 24 . 10.1016/S0021-9258(19)40646-7 . free .
• Langberg SR, Moss B . Post-transcriptional modifications of mRNA. Purification and characterization of cap I and cap II RNA (nucleoside-2'-)-methyltransferases from HeLa cells. . J. Biol. Chem. . 256 . 19 . 10054–60 . 1981 . 10.1016/S0021-9258(19)68740-5 . 7275966 . free .
• Ishikawa K . Prediction of the coding sequences of unidentified human genes. VIII. 78 new cDNA clones from brain which code for large proteins in vitro . DNA Res. . 4 . 5 . 307–13 . 1998 . 9455477 . 10.1093/dnares/4.5.307 . vanc. Nagase T . Nakajima D . 3 . Seki . N . Ohira . M . Miyajima . N . Tanaka . A . Kotani . H . Nomura . N . free .
• Tsukamoto T, Shibagaki Y, Niikura Y, Mizumoto K . Cloning and characterization of three human cDNAs encoding mRNA (guanine-7-)-methyltransferase, an mRNA cap methylase . Biochem. Biophys. Res. Commun. . 251 . 1 . 27–34 . 1998 . 9790902 . 10.1006/bbrc.1998.9402 .
• Saha N, Schwer B, Shuman S . Characterization of human, Schizosaccharomyces pombe, and Candida albicans mRNA cap methyltransferases and complete replacement of the yeast capping apparatus by mammalian enzymes . J. Biol. Chem. . 274 . 23 . 16553–62 . 1999 . 10347220 . 10.1074/jbc.274.23.16553 . free .
• Yamada-Okabe T . The Candida albicans gene for mRNA 5-cap methyltransferase: identification of additional residues essential for catalysis . Microbiology . 145 . 11. 3023–33 . 2000 . 10589710 . 10.1099/00221287-145-11-3023 . vanc. Mio T . Kashima Y . 3 . Matsui . M . Arisawa . M . Yamada-Okabe . H . free.
• Wen Y, Shatkin AJ . Cap methyltransferase selective binding and methylation of GpppG-RNA are stimulated by importin-α . Genes Dev. . 14 . 23 . 2944–9 . 2001 . 11114884 . 10.1101/gad.848200 . 317093 .
• Strausberg RL . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . vanc. Feingold EA . Grouse LH . 3 . Derge . JG . Klausner . RD . Collins . FS . Wagner . L . Shenmen . CM . Schuler . GD . 2002PNAS...9916899M . free .
• Gerhard DS . The Status, Quality, and Expansion of the NIH Full-Length cDNA Project: The Mammalian Gene Collection (MGC) . Genome Res. . 14 . 10B . 2121–7 . 2004 . 15489334 . 10.1101/gr.2596504 . 528928 . vanc. Wagner L . Feingold EA . 3 . Shenmen . CM . Grouse . LH . Schuler . G . Klein . SL . Old . S . Rasooly . R .
• Shafer B, Chu C, Shatkin AJ . Human mRNA Cap Methyltransferase: Alternative Nuclear Localization Signal Motifs Ensure Nuclear Localization Required for Viability . Mol. Cell. Biol. . 25 . 7 . 2644–9 . 2005 . 15767670 . 10.1128/MCB.25.7.2644-2649.2005 . 1061643 .

Notes and References

1. Pillutla RC, Shimamoto A, Furuichi Y, Shatkin AJ . Human mRNA capping enzyme (RNGTT) and cap methyltransferase (RNMT) map to 6q16 and 18p11.22-p11.23, respectively . Genomics . 54 . 2 . 351–3 . Jan 1999 . 9828141 . 10.1006/geno.1998.5604 .
2. Pillutla RC, Yue Z, Maldonado E, Shatkin AJ . Recombinant human mRNA cap methyltransferase binds capping enzyme/RNA polymerase IIo complexes . J Biol Chem . 273 . 34 . 21443–6 . Sep 1998 . 9705270 . 10.1074/jbc.273.34.21443 . free .
3. Web site: Entrez Gene: RNMT RNA (guanine-7-) methyltransferase.