Direct demonstration that the abundant 6-kilobase herpes simplex virus type 1 mRNA mapping between 0.23 and 0.27 map units encodes the major capsid protein VP5.

The two partially colinear 6-kilobase (kb) and 1.5-kb mRNAs mapping between 0.23 and 0.27 map units on the herpes simplex virus type 1 genome were precisely located. The 5' end of the 6-kb mRNA was located 28 bases downstream of the sequence ATATATT and was 10 bases to the left of the BamHI site at 0.268. This position is ca. 90 bases to the left of our earlier reported sequence (R. J. Frink, K. G. Draper, and E. K. Wagner, Proc. Natl. Acad. Sci. U.S.A. 78:6139-6143, 1981). We used a polyclonal antibody made against purified herpes simplex virus type 1 VP5 to demonstrate that the 155,000-dalton translation product of the 6-kb mRNA is this capsid protein. The antibody did not react with the 35,000-dalton translation product of the 1.5-kb mRNA. We also confirmed our identification of VP5 as the translation product of the 6-kb mRNA by comparison of tryptic peptides of the in vitro-translated protein and authentic VP5.