Revised genetic map of MVC. (A) The genetic map of MVC drawn to scale, highlighting the P6 promoter, splice donors (D) and acceptors (A), and the proximal (pA)p and distal (pA)d polyadenylation sites. The numbers denote the nucleotide positions within the MVC genome. The newly identified splice site (1D′1A), as used in RNAs R1′ and R2′, is incorporated in the map. The locations of the cap gene and (pA)p probes relative to the MVC genome are shown. (B) Diagram (not to scale) indicating the relative locations of the NP1 termination mutants NP1-2735TAG, NP1-2740TAA, and NP1-2839TAA and the NP1-5XPro mutant.