FIG. 9.
Analysis of virally mediated replication and cleavage of test plasmids containing the synthetic TRS arrays. Plasmids containing the HHV-6B oriLyt and DRR-DRL junction alone (pCO) or in combination with either the S-TRS (pCO-s7 and -s17) or C-TRS (pCO-c16 and -c31) array or both (pCO-c16/s17) were introduced into HHV-6B-infected J-Jahn cells. Ninety-six hours later, cells were collected and extrachromosomal DNA was harvested. This DNA was digested with DpnI plus XmnI and was subjected to Southern blot analysis with a radiolabeled pKS probe. Shown is a photograph of the resulting autoradiogram. Numbers correspond to the sizes of λ HindIII DNA fragments (in kilobases). Cleavage of replicated (DpnI-resistant) plasmid DNA with XmnI should give rise to unit length plasmid monomers (approximately 4.8 to 5.2 kb) (upper arrowhead) and to two terminal fragments of roughly 3.8 and 1.0 kb, reflecting specific cleavage of replicated plasmid concatemers. Of these terminal fragments, only the larger molecules were detected by the plasmid probe used (lower arrowhead).