5′ End of rna with triphosphate group pppNp phosphohydrolase p N pNp G GTP guanylyltransferase PP GpppNp adoMet guanine-7-methyltransferase doRcy GpppNp doMet 2-O-methyltransferase doho m'GpppmNp (b) 5' End of RNA with cap