Figure 3. UV cross-linking of model vRNA and cRNA promoters to hybrid polymerases.

Purified and quantified polymerases were incubated, in (A), (C) and (E), with ³²P-labelled 3′ strand of the vRNA promoter in the presence of the unlabelled 5′ strand of the vRNA promoter, or in (B), (D) and (F), with ³²P -labelled 3′ strand of the cRNA promoter in the presence of the unlabelled 5′ strand of the cRNA promoter. (A), (B) Hybrids between HK (H) and WSN (W), as indicated. (C), (D) Hybrids between VN (V) and NT (N), as indicated. (E), (F) WSN (W) polymerase was compared to hybrid polymerases of the PA of NT (PA-N), HK (PA-H) or VN PA (PA-V) with PB1 and PB2 from WSN. Relative activity is % relative to WSN from at least 3 independent experiments. Inset square panels show typical gels. * and ** indicate statistically significant differences (from W or N) at p<0.05 and p<0.01, respectively, in a Student's t-test.