Identification and Analysis of White Spot Syndrome Virus (wssv) Envelope Protein Vp41a

White spot syndrome virus (WSSV) is the causative agent of a disease that has led to severe mortalities of cultured shrimp in Taiwan and many other countries. WSSV, a kind of large enveloped DNA virus, has a wide host range among crustaceans. During the first stage to infect a target cell, the enveloped virus must combine itself with the receptor on the host cell membrane via an envelope protein. In WSSV, binding of envelope protein with the receptor of the host cell membrane was revealed in a number of previous studies. WSSV envelope proteins were also considered to form a protein complex, at some stage in all research to be named “infectome”. The WSSV envelope protein VP41A, with the predicted molecular weight of about 41 kDa and having a transmembrane region at its C-terminus, is identified in this study. The interaction of VP41A with the virus’ major envelope protein VP26 is revealed by His pull-down and liquid chromatography tandem mass spectrometry. Furthermore, the protein-protein interaction of VP41A with VP28 and VP56 is verified by far western blotting. This data indicate that VP41A participates in the formation of a WSSV protein complex that may be involved in WSSV infection. These findings may identify certain areas for further WSSV research.