MRNA (guanine-N7-)-methyltransferase

In enzymology, a mRNA (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. 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.

Structural studies
As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes and.