ORF3
Domain
The PSAP motif is necessary for the release of membrane-wrapped virions from infected cells.
Function
Small multifunctional phosphoprotein involved in virion morphogenesis, egress and counteracting host innate immunity (PubMed:19339479, PubMed:21068219, PubMed:28096411, PubMed:30532200). Plays critical roles in the final steps of viral release by interacting with host TSG101, a member of the vacuolar protein-sorting pathway and using other cellular host proteins involved in vesicle formation pathway (PubMed:19339479, PubMed:21068219). Acts also as a viroporin and forms ion conductive pores allowing viral particle release (PubMed:28096411). Impairs the generation of type I interferon by down-regulating host TLR3 and TLR7 as well as their downstream signaling pathways (PubMed:27270888, PubMed:29872132). Down-regulates the phosphorylation of host IRF3 via the interaction with host SIRP-alpha, thereby inhibiting IFN-I expression (PubMed:26492885). Interacts with host microtubules (PubMed:19369329).
Post-translational modifications
Palmitoylated in the N-terminus.
Sequence Similarities
Belongs to the hepevirus ORF3 protein family.
Cellular localization
- Host endoplasmic reticulum membrane
- Lipid-anchor
- Host cytoplasm
- Host cytoskeleton
- Virion
- Host cell membrane
- Lipid-anchor
- The N-terminal region seems to associate with the cytoskeleton probably via one of its hydrophobic regions (PubMed:19369329). Present on the surface of the membrane-wrapped virions (PubMed:19339479).
Alternative names
Protein ORF3, pORF3, Vp13, ORF3