Cell-type capping

RNAs are capped by a viral reaction similar to that in the cell. GTP is first covalently bound to GTase as GTase-GMP, which is then transferred to the processed ppRNA to form a GpppN RNA. The RNA is further N7-methylated and 2'O-methylated by two other viral enzymes.

RNA triphosphatase: Rhea 67004
GTase-Lys-GMP reaction: (reoviridae, Poxviridae)
GTase-Arg-GMP reaction: (Flaviridae)
Guanylyl transfer on viral RNA: Rhea 67012
N7methyltransferase: Rhea 67008
2'O Mtase reaction: Rhea 67020