FIG 4.
Immunoblotting of capsids of UL25 null mutant. Capsids of HSV-1 mutant virus vJB92 (lacking the entire UL25 ORF) were purified from infected CV1 cells on a continuous sucrose gradient as described in Materials and Methods. Proteins in each fraction were precipitated with TCA and dissolved in SDS loading buffer. Fractions 2 to 19 were collected from the bottom to the top of the gradient. Proteins within these fractions and the unfractionated lysate (far-right lane) were separated on a 10% SDS-PAGE gel, followed by immunoblotting with antibodies to pUL31, pUL17, VP5, or viral scaffold proteins VP22a and VP21, respectively. Bound antibodies were revealed by ECL.