This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing nucleotide groups (nucleotidyltransferases).op The systematic name of this enzyme class is GTP:mRNA guanylyltransferase. Other names in common use include mRNA capping enzyme, messenger RNA guanylyltransferase, and Protein 2.

References

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 (7): 2525–9. Bibcode:1975PNAS...72.2525E. doi:10.1073/pnas.72.7.2525. PMC 432801. PMID 1058472.
Groner Y, Gilboa E, Aviv H (1978). "Methylation and capping of RNA polymerase II primary transcripts by HeLa nuclear homogenates". Biochemistry. 17 (6): 977–82. doi:10.1021/bi00599a005. PMID 629955.
Itoh N, Yamada H, Kaziro Y, Mizumoto K (1987). "Messenger RNA guanylyltransferase from Saccharomyces cerevisiae Large scale purification, subunit functions, and subcellular localization". J. Biol. Chem. 262 (5): 1989–95. doi:10.1016/S0021-9258(18)61609-6. PMID 3029058.
Martin SA, Moss B (1975). "Modification of RNA by mRNA guanylyltransferase and mRNA (guanine-7-)methyltransferase from vaccinia virions". J. Biol. Chem. 250 (24): 9330–5. doi:10.1016/S0021-9258(19)40647-9. PMID 1194287.
Martin SA, Paoletti E, Moss B (1975). "Purification of mRNA guanylyltransferase and mRNA (guanine-7-) methyltransferase from vaccinia virions". J. Biol. Chem. 250 (24): 9322–9. doi:10.1016/S0021-9258(19)40646-7. PMID 1194286.

Transferases: phosphorus-containing groups (EC 2.7)

2.7.1-2.7.4:
phosphotransferase/kinase
(PO₄)

2.7.1: OH acceptor	Hexo- Gluco- Fructo- Hepatic Galacto- Phosphofructo- 1 Liver Muscle Platelet 2 Riboflavin Shikimate Thymidine ADP-thymidine NAD⁺ Glycerol Pantothenate Mevalonate Pyruvate Deoxycytidine PFP Diacylglycerol Phosphoinositide 3 Class I PI 3 Class II PI 3 Sphingosine Glucose-1,6-bisphosphate synthase
2.7.2: COOH acceptor	Phosphoglycerate Aspartate kinase
2.7.3: N acceptor	Creatine
2.7.4: PO₄ acceptor	Phosphomevalonate Adenylate Nucleoside-diphosphate Uridylate Guanylate Thiamine-diphosphate

2.7.6: diphosphotransferase
(P₂O₇)

2.7.7: nucleotidyltransferase
(PO₄-nucleoside)

Polymerase

DNA polymerase	DNA-directed DNA polymerase I/A γ θ ν T7 Taq II/B α δ ε ζ Pfu III/C IV/X β λ μ TDT V/Y η ι κ RNA-directed DNA polymerase Reverse transcriptase Telomerase
RNA polymerase	Template-directed RNA polymerase I II III IV V ssRNAP POLRMT Primase 1 2 PrimPol RNA-dependent RNA polymerase Polyadenylation PAP PNPase

Phosphorolytic
3' to 5' exoribonuclease

Nucleotidyltransferase

Guanylyltransferase

mRNA capping enzyme

Other

2.7.8: miscellaneous

Phosphatidyltransferases	CDP-diacylglycerol—glycerol-3-phosphate 3-phosphatidyltransferase CDP-diacylglycerol—serine O-phosphatidyltransferase CDP-diacylglycerol—inositol 3-phosphatidyltransferase CDP-diacylglycerol—choline O-phosphatidyltransferase
Glycosyl-1-phosphotransferase	N-acetylglucosamine-1-phosphate transferase

2.7.10-2.7.13: protein kinase
(PO₄; protein acceptor)

2.7.10: protein-tyrosine	see tyrosine kinases
2.7.11: protein-serine/threonine	see serine/threonine-specific protein kinases
2.7.12: protein-dual-specificity	see serine/threonine-specific protein kinases
2.7.13: protein-histidine	Protein-histidine pros-kinase Protein-histidine tele-kinase Histidine kinase

v t e Enzymes
Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Diffusion-limited enzyme Cofactor Enzyme catalysis
Regulation	Allosteric regulation Cooperativity Enzyme inhibitor Enzyme activator
Classification	EC number Enzyme superfamily Enzyme family List of enzymes
Kinetics	Enzyme kinetics Eadie–Hofstee diagram Hanes–Woolf plot Lineweaver–Burk plot Michaelis–Menten kinetics
Types	EC1 Oxidoreductases (list) EC2 Transferases (list) EC3 Hydrolases (list) EC4 Lyases (list) EC5 Isomerases (list) EC6 Ligases (list) EC7 Translocases (list)

Structural studies

References