FIG. 3.

Identification of region of RTA required for DNA replication. (A) Schematic diagram of a set of deletion mutants of pSG-C50. Deleted amino acids are shown by the downward sloping lines. DBD, DNA binding domain. (B) Expression levels of SG-C50 and its derivatives were monitored by Western blotting with an antibody specific to Gal4 protein. (C) pOri-2xGal4 was introduced into BCBL-1 cells along with SG-C50 and a series of its deletion mutants. The RTA expression vectors were included to initiate lytic DNA replication. (C) Replicated (Rep'd) DNA was distinguished from input DNA by DpnI digest and detected by Southern blotting with ³²P-labeled pBluescript (pBlue) plasmid. The replication rate of each mutant relative to that of wild-type pOri-A was calculated by comparing the normalized intensity of the replicated DNA band with that of wild-type pOri-A. Each number is the average of results from two independent experiments. The transcription ability of each mutant was determined by a luciferase assay with the 13F-2xGal4 reporter construct (31).