EC 2.7.7.88     
Accepted name: GDP polyribonucleotidyltransferase
Reaction: (5′)pppAACA-[mRNA] + GDP = diphosphate + G(5′)pppAACA-[mRNA] (overall reaction)
(1a) (5′)pppAACA-[mRNA] + [protein L]-L-histidine = diphosphate + [protein L]-L-histidyl-(5′)phosphonato-AACA-[mRNA] + H2O
(1b) [protein L]-L-histidyl-(5′)phosphonato-AACA-[mRNA] + GDP + H2O = [protein L]-L-histidine + G(5′)pppAACA-[mRNA]
Other name(s): PRNTase; 5′-triphospho-mRNA:GDP 5′-phosphopolyribonucleotidyltransferase [G(5′)ppp-mRNA-forming]
Systematic name: (5′)pppAACA-[mRNA]:GDP 5′-phosphopolyribonucleotidyltransferase [(5′)pppAACA-[mRNA]-forming]
Comments: The enzyme from non-segmented negative strain (NNS) viruses (e.g. rhabdoviruses and lyssaviruses) is specific for mRNAs with sequences starting with AACA. cf. EC 2.7.7.50, mRNA guanylyltransferase.
References:
1.  Ogino, T. and Banerjee, A.K. Unconventional mechanism of mRNA capping by the RNA-dependent RNA polymerase of vesicular stomatitis virus. Mol. Cell 25 (2007) 85–97. [PMID: 17218273]
2.  Ogino, T. and Banerjee, A.K. Formation of guanosine(5′)tetraphospho(5′)adenosine cap structure by an unconventional mRNA capping enzyme of vesicular stomatitis virus. J. Virol. 82 (2008) 7729–7734. [PMID: 18495767]
3.  Ogino, T., Yadav, S.P. and Banerjee, A.K. Histidine-mediated RNA transfer to GDP for unique mRNA capping by vesicular stomatitis virus RNA polymerase. Proc. Natl. Acad. Sci. USA 107 (2010) 3463–3468. [PMID: 20142503]
4.  Ogino, T. and Banerjee, A.K. The HR motif in the RNA-dependent RNA polymerase L protein of Chandipura virus is required for unconventional mRNA-capping activity. J. Gen. Virol. 91 (2010) 1311–1314. [PMID: 20107017]
5.  Ogino, T. and Banerjee, A.K. An unconventional pathway of mRNA cap formation by vesiculoviruses. Virus Res. 162 (2011) 100–109. [PMID: 21945214]
6.  Ogino, M., Ito, N., Sugiyama, M. and Ogino, T. The rabies virus L protein catalyzes mRNA capping with GDP polyribonucleotidyltransferase activity. Viruses 8:144 (2016). [PMID: 27213429]
[EC 2.7.7.88 created 2015, modified 2020]