FIG. 1.

Schematic representation of substrates used in this study. For Ad3′, Ad major late sequences representing the last 80 nt of the first intron (line) and first 48 nt of the second exon (open box), the branch point (BP), and the pyrimidine tract (pyr) are shown. For the NRS, 701 and 932 indicate the endpoints of the RSV sequence. NRS-Ad3′ is a chimeric substrate in which the NRS is linked to Ad3′. The relevant wild-type RSV (nt 913 to 926) and Ad sequences are shown below this construct. Mutations in the NRS-Ad3′ derivatives are shown below the wild-type sequence, with mutations in lowercase and underlined. RG11-Ad3′, mU1-Ad3′, and NRS67-Ad3′ are chimeric substrates containing the indicated mutations in the NRS. NRS-Ad3′mutBP, NRS-Ad3′mutPyr, and NRS-Ad3′mutAG are chimeric substrates containing the indicated mutations in the branch point, pyrimidine tract, and terminal AG of Ad3′, respectively. The diagram is not drawn to scale.