Effects of Hypervariable Regions in Spike Protein on Pathogenicity, Tropism, and Serotypes of Infectious Bronchitis Virus.

•For the first time using reverse genetics to reveal the roles of HVRs in coronavirus.•The HVRs exchange from IBV S1 subunit weakened the adsorption during IBV infection in vitro.•The HVRs exchange in IBV S1 reduced ARV with Beaudette, but not sufficiently change serotypes.•The recombinant IBVs provided insights into reverse genetic vaccines.