– Coordinates the incorporation of A36 into intracellular enveloped virion (IEV) membranes and, subsequently, the production of actin tails. Therefore plays an essential role in efficient cell-to-cell spread of viral particles. Vaccinia virus (strain Copenhagen) OPG161 Protein (A33R, His) is expressed in Baculovirus insect cells with N-10xHis and C-Myc tag. The predicted molecular weight is 18.3 kDa and the accession number is P68616.