A conserved opal termination codon optimizes a temperature-dependent tradeoff between protein production and processing in alphaviruses.

ABSTRACT: Alphaviruses are enveloped, single-stranded, positive-sense RNA viruses that often require transmission between arthropod and vertebrate hosts for their sustained propagation. Most alphaviruses encode an opal (UGA) termination codon in nonstructural protein 3 (nsP3) upstream of the viral polymerase, nsP4. The selective constraints underlying the conservation of the opal codon are poorly understood. Using primate and mosquito cells, we explored the role and selective pressure on the nsP3 opal codon through extensive mutational analysis in the prototype alphavirus, Sindbis virus (SINV). We found that the opal codon is highly favored over all other codons in primate cells under native 37°C growth conditions. However, this preference is diminished in mosquito and primate cells grown at a lower

SUBMITTER: Bhattacharya T 

PROVIDER: S-EPMC11370586 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature