Term Name:	7-methylguanosine cap hypermethylation
Synonyms:	2,2,7-trimethylguanosine cap formation, conversion of m(7)G to m(3)G, hypermethylation of snoRNA cap, hypermethylation of snRNA cap, m(7)G cap hypermethylation, snoRNA capping, snRNA capping, TMG cap formation
Definition:	Hypermethylation of the 7-(mono)methylguanosine (m(7)G) cap structure at the 2' position of the guanosine residue to convert a mono-methylated cap to a 2,2,7-trimethylguanosine cap structure. This type of cap modification occurs on small nuclear RNAs (snRNAs) and small nucleolar RNAs (snoRNAs) and is dependent on prior guanine-N7 methylation.
Ontology:	GO: Biological Process [GO:0036261]    QuickGO    AmiGO