mRNA (2'-O-methyladenosine-N6-)-methyltransferase

In enzymology, a mRNA (2'-O-methyladenosine-N⁶-)-methyltransferase (EC 2.1.1.62) is an enzyme that catalyzes the chemical reaction

S-adenosyl-L-methionine + m⁷G(5')pppAm ${\displaystyle \rightleftharpoons }$ S-adenosyl-L-homocysteine + m⁷G(5')pppm⁶Am (mRNA containing an N⁶,2'-O-dimethyladenosine cap)

Thus, the two substrates of this enzyme are S-adenosyl methionine and m⁷G(5')pppAm, whereas its two products are S-adenosylhomocysteine and m⁷G(5')pppm⁶Am (mRNA containing an N⁶,2'-O-dimethyladenosine cap).

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 (2'-O-methyladenosine-N⁶-)-methyltransferase. Other names in common use include messenger ribonucleate 2'-O-methyladenosine NG-methyltransferase, S-adenosyl-L-methionine:mRNA, and (2'-O-methyladenosine-6-N-)-methyltransferase.