Herpesvirus protein ORF56 reduces immune response by targeting MAVS-B for degradation in polyploid gibel carp

The viral protein ORF56 of Carassius auratus herpesvirus (CaHV) selectively degrades MAVS-B in polyploid gibel carp.

• ORF56 diminishes interferon (IFN) production by targeting MAVS-B, not MAVS-A.
• This degradation occurs via the autophagy pathway in gibel carp with two triploid sets of chromosomes.
• Screening assays show that ORF56 suppresses IFN promoter activity and enhances CaHV replication.
• Co-expression of ORF56 and MAVS-B leads to increased autophagic activity.
• Only the selective autophagy receptor OPTN-B is involved in the degradation of MAVS-B by ORF56.

Simplified