FIG. 5.

Contribution of SPP381 to the efficiency of pre-mRNA splicing in vivo. RNA was isolated from wild-type yeast (lanes 1 and 2) and the spp381::LEU2 disruptant before (lane 5) and after transformation with GAL1::SPP381HA (lanes 3 and 4) or with GAL1::spp381ΔPEST-HA (lane 6). Galactose (gal) or glucose (glu) was used to activate or repress the GAL1 fusion constructs as indicated. Lanes 7 to 12, RNA from the untransformed prp38-1 mutant (lanes 7 and 8) and the same strain after transformation with the high-copy-number (i.e., YEp112) plasmid bearing SPP381 (lanes 9 and 10) or its ΔPEST (YEplac112-based) derivative (lanes 11 and 12). The RNA was recovered from cultures grown continuously at the permissive temperature for prp38-1 (23°C) or after 2.5 h at the restrictive temperature (37°C). The positions of pre-mRNA (P) and spliced mRNA (M) are indicated by arrowheads. (A) Hybridization with an RP51A-specific intron-plus-exon probe. (B) Hybridization with a CYH2-specific intron-plus-exon probe. (C) Hybridization with an ADE3 gene body probe.