Unpaired 5' ppp-nucleotides, as found in arenavirus double-stranded RNA panhandles, are not recognized by RIG-I.

ABSTRACT: Arenavirus and bunyavirus RNA genomes are unusual in that they are found in circular nucleocapsids, presumably due to the annealing of their complementary terminal sequences. Moreover, arenavirus genome synthesis initiates with GTP at position +2 of the template rather than at the precise 3' end (position +1). After formation of a dinucleotide, 5' pppGpC(OH) is then realigned on the template before this primer is extended. The net result of this "prime and realign" mechanism of genome initiation is that 5' pppG is found as an unpaired 5' nucleotide when the complementary genome ends anneal to form a double-stranded (dsRNA) panhandle. Using 5' pppRNA made in vitro and purified so that all dsRNA side products are absent, we have determined that both this 5' nucleotide overhang, as well as mi

SUBMITTER: Marq JB 

PROVIDER: S-EPMC2881745 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature