5′ End ofrna with triphosphate group pppNp phosphohydrola ppP G GTP guanylyltransferase PP GpppNp adoMet guanine-7-methyltransferase docy m'GpppNp adoMet 2-O-methyltransferase adoho m'GpppmNp (b) 5 End of RNA with cap