a 5'-end (N(7)-methyl 5'-triphosphoguanosine)-ribonucleoside in mRNA + H2O => N(7)-methyl-GMP + a 5'-end diphospho-ribonucleoside in mRNA + 2 H(+)
a 5'-end (n(7)-methyl 5'-triphosphoguanosine)-ribonucleoside in mrna + h2o => n(7)-methyl-gmp + a 5'-end diphospho-ribonucleoside in mrna + 2 h(+)