Unfixed SV40 chromosomes were isolated from cells infected with cs1085 mutant virus for 8 hours and subjected to an ISFIP/ReChIP analysis with antibodies to unacetylated histone H4 and histone H3 and hyperacetylated histone H4 and H3 as described in the materials and methods The samples were amplified by simplex PCR with primer sets to the early and late regions. The position of the amplification product from the wild-type 776 DNA is indicated. 5A: Lane 1: ISFIP input fraction; lane 2: ChIP with 10 μl of unacetylated histone H4 antibody (ISFIP); lane 3: ChIP with 10 μl of unacetylated histone H3 antibody (ISFIP); lane 4: ReChIP input fraction; lane 5: ChIP with 10 μl of unacetylated histone H4 antibody (ReChIP); lane 6: ChIP with 10 all of unacetylated histone H3 antibody (ReChIP) ChIP with 10 μl of unacetylated histone H3 antibody (ReChIP). 5B: Lane 1: ISFIP input fraction; lane 2: ChIP with 7.5 μl of hyperacetylated histone H4 antibody (ISFIP); lane 3: ChIP with 10 μl of hyperacetylated histone H3 antibody (ISFIP); lane 4: ReChIP input fraction; lane 5: ChIP with 7.5 μl of hyperacetylated histone H4 antibody (ReChIP); lane 6: ChIP with 10 μl of hyperacetylated histone H3 antibody (ReChIP)
The PCR products in the ISFIP and ReChIP lanes were amplified from one half of the total amount of DNA obtained from each of the samples. The PCR products in the input lanes were amplified from one fourth of the total amount of DNA present in each of the input samples. Similar results were obtained from at least three separate preparations of SV40 chromosomes at 8 hours post-infection.