Sequence variation in the RNA Polymerase gene of Junin virus strains

GOÑI, S.E.; ROMANOWSKI, V.; GHIRINGHELLI, P.D.; LOZANO, M.E.

Santa Catarina

Congreso; XIV Encontro Nacional de Virologia; 2003

Sociedad Brasilera de Virologia

Arenaviridae comprises 20 recognized virus species with a bipartite ssRNA genome and an ambisense coding strategy. The virions are enveloped and include non-equimolar amounts of each genomic RNA species, designated L (ca. 7200 nt) and S (ca. 3500 nt). S RNA sequences are available for most arenaviruses, but only the complete genomes of Tacaribe, LCM, Pichindé and Lassa viruses are known to date. Some arenaviruses have been recognized as etiological agents for serious human diseases. In Argentina, three native arenaviruses have been described, including Junín virus -the ethiological agent of Argentine hemorrhagic fever (AHF), an acute disease with high mortality rate. In the '80s, the Junín virus Candid#1 strain was developed as a live attenuated vaccine for AHF. Although the attenuated phenotype of this strain was confirmed in clinical trials, the molecular basis of virulence attenuation is still unknown. In this work, we report nucleotide sequences for L RNA of Candid#1 and its more virulent ancestor XJ#44. Their relationship to wild-type Junín virus MC2 strain and other closely and distantly related arenaviruses have been examined. Comparisons of the nucleotide and amino acid sequences of Candid#1 and the wild-type strains revealed some changes that are unique to the vaccine strain. These changes can be provisionally associated with the attenuated phenotype