FIG. 9.

Accumulation of viral DNA in MEFs detected by Southern blotting. Wild-type and mutant MEFs grown in T25 flasks were exposed to 0.1 PFU of HSV-1(F) per cell. After 24 h, total cellular DNA was extracted and digested with BamHI overnight. One-fourth of the digested DNA was separated in a 0.8% agarose gel, and the total viral DNA yield was determined by hybridization with ³²P-labeled BamHI S fragment of the viral genomic DNA. The yield of viral DNA from each mutant MEF line was normalized against the WT control line. Note that the BamHI S fragment hybridizes with terminal and junction fragments of HSV-1 DNA. The terminal fragment of the L component and the L-S junction fragment contain variable numbers of the a sequences that are reflected in the formation of multiple bands.