Infectious Bursal Disease Virus non-structural protein VP5 is not a transmembrane protein.

Infectious Bursal Disease Virus (IBDV) causes a highly relevant poultry disease that affects young chickens causing, among other effects, immunosuppression. IBDV is a bi-segmented double stranded RNA virus. The smaller ORF of larger RNA segment encodes VP5, a 17-kDa non-structural protein. Although it is an important protein for viral replication cycle, the definition of its specific role and subcellular localization remains unclear. In the present work we demonstrate, using imaging techniques, that VP5 is not a type II transmembrane protein but an intracellular membrane-associated protein. This finding might provide evidences of VP5 interaction with cellular proteins and its functions.