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.

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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

Viral molecular biology Virion
Virus entry
Virus latency
Transcription and replication
Host-virus interactions
Virus exit
Viral mRNA capping Cell-type capping
Alpha-type capping
Nido-type capping
Mononega-type capping
VPG cap
Polynega-type cap-snatching
Toti-type cap-snatching
Significant viruses Poxviridae
Sedoreoviridae
Flaviviridae
virusRNA TPase
Rhea 67004		GTase
Rhea 67012		N7MTase
Rhea 67008		2'O methylase
Rhea 67020
Vaccinia (Poxvirus)D1RD1R
(GTase-Lys-GMP)		D1R +D12L J3R
Flaviviruses (Dengue virus)NS3NS5
(GTase-Arg-GMP)		NS5NS5
Orbivirus(Bluetongue virus)VP4VP4
(GTase-Lys-GMP)		VP4VP4
Mammalian orthoreovirusLambda1Lambda2
(GTase-Lys-GMP)		Lambda2Lambda2
MimivirusMimiCE MimiCE
(GTase-Lys-GMP)		MimiCE
BaculovirusLEF-4LEF-4
(GTase-Lys-GMP)		UnknownAc69
ChlorellavirusA449RA103R
(GTase-Lys-GMP)		UnknownUnknown


Mimivirus TPase
VP4 bluetongue virus TPase, GTAse, 2'O MTase