(A) MDBK cells were infected with the vBoHV-1-UL21-HA or BoHV-1 viruses at a MOI of 3. At 18 hpi, cells were harvested and immunoprecipitated with anti-HA antibody conjugated magnetic agarose beads, and the precipitated proteins were loaded onto a 12% SDS-polyacrylamide gel and silver stained. Lane A, the bead eluate; lane B, the third wash; and lane C, the flow-through. Protein molecular weight markers in kDa are indicated to the left of the gel. (B) Mass spectrometry analysis of immunoprecipitated proteins along with the interacting proteins that correspond to the proteins. The expected 60-kDa UL21-HA band, as were 36-kDa band, which were confirmed to be UL16 by LC-MS (C) MDBK cells were infected with the vBoHV-1-UL21-HA or BoHV-1 viruses, and proteins were precipitated using anti-HA antibody-conjugated magnetic agarose beads. The beads were electrophoresed and transferred onto PVDF membranes. Then, the membranes were probed with a mouse anti-HA-tag antibody and with the antisera indicated on the right side of the figure. Beta-actin was used as the internal reference control. The migration positions of proteins are shown in kDa to the left of the gel.