STRUCTURE AND ROLE OF THE HERPES-SIMPLEX VIRUS-DNA TERMINI IN INVERSION, CIRCULARIZATION AND GENERATION OF VIRION DNA

The herpes simplex virus genome consists of 2 components, L [long] and S [short], which invert relative to each other during viral replication. The a sequence is present at the genomic termini in direct orientation and at the L-S junction in inverted orientation. Insertion of a fragment spanning the L-S junction into the viral genome causes additional inversions. The nucleotide sequence of the genomic termini was determined and the insertion of either the free S terminus or the L terminus was shown to cause inversions in the viral genome. Evidently, the a sequence is the inversion-specific sequence, linear unit-length molecules packaged in virions are generated by cleavage between adjacent copies of the a sequence, cleavage produces 3'' single-base extensions on the genomic termini and the signal for cleavage is contained within the a sequence.