Figure 3.

Verifying the exon trapping and mutagenesis approach for identifying distant branch points. The rat α-tropomyosin minigene (TS3St) and a derivative (ΔBP-175), in which the previously determined dBP of exon 3 had been mutated, and an additional mutant (ΔBP-175 -182) were transfected into HeLa cells. Splicing of transiently expressed RNA was analyzed by RT-PCR with a [³²P]labeled primer in the PCR reaction. dBP, distant branch point; RT-PCR, reverse transcriptase polymerase chain reaction; WT, wild type.