FIG. 4.
(A) Template specificity of CYDV RdRp. RdRp reactions containing [32P]UTP were carried out either with a membrane-bound CYDV RNA polymerase containing endogenous CYDV RNA template (lane 1) or with BAL 31 nuclease-treated CYDV RNA polymerase with various added templates in the absence or presence of bVPg (lanes 2 to 4). The reactions were carried out as described in the text and included no added CYDV virion RNA (RNA) (lane 1), RNA only (lane 2), RNA plus bVPg (lane 3), or RNA plus bVPg and treatment with S1 nuclease (S1) prior to PAGE (lane 4). (B) Lane 1, no additions; lane 2, 323 3′-terminal nucleotides of CYDV minus-strand template RNA [(−) RNA]; lane 3, (−) RNA plus bVPg. Lane 1 in both panels C and D contained no RNA. Lanes 2 to 4 and 2 to 8, respectively, in panels C and D all contained bVPg and various virion RNAs—plus-stranded (+) or minus-stranded (−) virion RNA or DNA fragment templates as described in the text and shown in their abbreviated forms. All RNA products were analyzed by electrophoresis in 4% (A, C) or 8% (B, D) polyacrylamide gels containing 8 M urea. The sizes and mobilities of the products are described in the text and are indicated by arrows.