Figure 6.

Constructs of Mutant Vectors with Modifications of Primer-Binding Site Sequences

(A) Mutations of primer-binding site within the MLV RNA genome. Additional primer-binding sites were added or point mutations were introduced in the primer-binding site. The two bases in the primer-binding site that were point-mutated are underlined. Six mutants with a point mutation were constructed: 5th base of primer-binding site (G) to A (termed 5GA), to C (5GC), to T (5GT), and 9th base of primer-binding site (C) to A (9CA), to G (9CG), and to T (9CT). Host tRNA binding to primer-binding site is also depicted. (B) Schematic diagram of the construction of double mutants. Primer-binding site mutation and ZFD insertion into integrase were applied simultaneously during construction of the double-mutant vectors. (C) Schematic diagram of the production of five double mutants. Mutations of primer-binding site were introduced into pCLPIT GFP, which encodes the vector genome. DNA encoding each zinc-finger domain was introduced into pCMV Gag-Pol-ZFD, which expresses the MLV Gag-Pol polyprotein. PBS, primer-binding site.