Arenavirus Gene Structure and Organization

Abstract

For rhabdoviruses, paramyxoviruses, orthomyxoviruses, and some members of the Bunyaviridae, all the proteins are translated from the viral-complementary RNA sequence. This is in contrast to the genetic strategy of picornaviruses, caliciviruses, coronaviruses, togaviruses, flaviviruses, and retroviruses, whose proteins are all translated from the viral RNA sequence (i. e., viral RNA, or sequences corresponding to viral RNA sequences, functions as an mRNA species). The former group of single-stranded RNA viruses are described as negative- stranded RNA viruses, the latter as positive-stranded RNA viruses. The negative-stranded RNA viruses have a virion RNA polymerase that is responsible for the synthesis of the viral-complementary mRNA species. Although the purified viral RNA of most of the positive-stranded viruses is infectious per se, this is not the case for retroviruses since they have a virion reverse transcriptase that forms an obligatory DNA intermediate during the initial stages of the viral infection process.