part of mRNA 5'-cap (guanine-N7-)-methyltransferase activity https://github.com/geneontology/go-ontology/issues/25788 https://github.com/geneontology/go-ontology/issues/30193 S-adenosyl-L-methionine:mRNA (guanine-N7-)-methyltransferase activity Reactome:R-HSA-77090 Reactome:R-HSA-9830848 Reactome:R-HSA-9684018 Reactome:R-HSA-9684017 Reactome:R-HSA-9684016 Reactome:R-HSA-9694492 S-adenosyl-L-methionine:mRNA (guanine-7-N-)-methyltransferase activity messenger RNA guanine 7-methyltransferase activity messenger ribonucleate guanine 7-methyltransferase activity Catalysis of the reaction: S-adenosyl-L-methionine + G(5')pppR-RNA = S-adenosyl-L-homocysteine + m7G(5')pppR-RNA. m7G(5')pppR-RNA is mRNA containing an N7-methylguanine cap; R may be guanosine or adenosine. molecular_function Reactome:R-HSA-9923104 MetaCyc:MRNA-GUANINE-N7--METHYLTRANSFERASE-RXN GO:0004482 Reactome:R-HSA-9694737 EC:2.1.1.56 Reactome:R-HSA-9694476 guanine-7-methyltransferase activity 7-methylguanosine mRNA capping N-methyltransferase activity mRNA methyltransferase activity RNA 5'-cap (guanine-N7)-methylation