Adaptive truncation of the S gene in IBV during chicken embryo passaging plays a crucial role in its attenuation.

ABSTRACT: Like all coronaviruses, infectious bronchitis virus, the causative agent of infectious bronchitis in chickens, exhibits a high mutation rate. Adaptive mutations that arise during the production of live attenuated vaccines against IBV often decrease virulence. The specific impact of these mutations on viral pathogenicity, however, has not been fully elucidated. In this study, we identified a mutation at the 3' end of the S gene in an IBV strain that was serially passaged in chicken embryos, and showed that this mutation resulted in a 9-aa truncation of the cytoplasmic tail (CT) of the S protein. This phenomenon of CT truncation has previously been observed in the production of attenuated vaccines against other coronaviruses such as the porcine epidemic diarrhea virus. We next discovered tha

SUBMITTER: Liang R 

PROVIDER: S-EPMC11315334 | biostudies-literature | 2024 Jul

REPOSITORIES: biostudies-literature