Interaction of white spot syndrome virus VP26 protein with actin.

VP26 protein, the product of the WSV311 gene of white spot syndrome virus (WSSV), is one of major structural proteins of virus. In this study, when purified virions were treated with Triton X-100 detergent, VP26 protein was present in both the envelope and the nucleocapsid fraction. We have rationalized this finding by suggesting that VP26 protein might be located in the space between the envelope and the nucleocapsid. By using a fluorescent probe method, we have investigated the interaction between VP26 protein and some proteins of host cells. Three major VP26-binding proteins were purified from crayfish hemocytes by affinity-chromatography, in which the protein with an apparent molecular mass of 42 kDa was identified as actin by mass spectrometry (MS). Moreover, the association of VP26 protein with actin microfilaments was confirmed by coimmunoprecipitation.