Replicase complex genes of Semliki Forest virus confer lethal neurovirulence.

ABSTRACT: Semliki Forest virus (SFV) is a mosquito-transmitted pathogen of small rodents, and infection of adult mice with SFV4, a neurovirulent strain of SFV, leads to lethal encephalitis in a few days, whereas mice infected with the avirulent A7(74) strain remain asymptomatic. In adult neurons, A7(74) is unable to form virions and hence does not reach a critical threshold of neuronal damage. To elucidate the molecular mechanisms of neurovirulence, we have cloned and sequenced the entire 11,758-nucleotide genome of A7(74) and compared it to the highly neurovirulent SFV4 virus. We found several sequence differences and sought to localize determinants conferring the neuropathogenicity by using a panel of chimeras between SFV4 and a cloned recombinant, rA774. We first localized virulence determinants

SUBMITTER: Tuittila MT 

PROVIDER: S-EPMC111978 | biostudies-literature | 2000 May

REPOSITORIES: biostudies-literature