On the role of VP3-PI3P interaction in birnavirus endosomal membrane targeting.

ABSTRACT: Birnaviruses are a group of double-stranded RNA (dsRNA) viruses infecting birds, fish, and insects. Early endosomes (EE) constitute the platform for viral replication. Here, we study the mechanism of birnaviral targeting of EE membranes. Using the Infectious Bursal Disease Virus (IBDV) as a model, we validate that the viral protein 3 (VP3) binds to phosphatidylinositol-3-phosphate (PI3P) present in EE membranes. We identify the domain of VP3 involved in PI3P-binding, named P2 and localized in the core of VP3, and establish the critical role of the arginine at position 200 (R₂₀₀), conserved among all known birnaviruses. Mutating R₂₀₀ abolishes viral replication. Moreover, we propose a two-stage modular mechanism for VP3 association with EE. Firstly, the carboxy-termina

SUBMITTER: Zanetti FA 

PROVIDER: S-EPMC11884790 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature