FIG. 3.

BglII restriction analysis reveals preferential usage of U5 over U3 LTR termini by SIV IN for full-site and half-site strand transfer. Standard strand transfer assays were performed with SIV IN and nonionic-detergent-lysed HIV-1 virions with the HIV-1 U5-U3 donor (469 bp). The products were separated on 1.5% agarose gels. The samples were not (−) or were (+) digested with BglII as indicated at the top. Lane 1, molecular size markers; lane 2, HIV-1 IN products; lane 3, BglII digestion of HIV-1 products; lane 4, SIV IN products; lane 5, BglII digestion of SIV IN products. The undigested circular half-site and full-site products of both reactions are marked on the left side along with the sizes of the DNA ladder. The BglII digestion products are shown on the right. The digested full-site products are indicated as LTR donor-target-LTR donor fragments.