Figure 1.

Screen to identify substances that promote exon Vb inclusion. (A) Schematic overview of the HTR2c gene. The dot indicates the start codon. The shaded area is used to construct the fluorescence-based screening reporter genes. The dotted area containing exon Va, Vb and IV is used to generate the RT–PCR-based reporter minigenes. (B) Reporter construct: the shaded area from the HTR2c gene in (A) was introduced into the reporter pFlare that can generate both GFP and RFP. Lines indicate methionine codons that were mutated. (C) Protein products generated by the reporter: inclusion of exon Vb creates GFP protein, and skipping of exon Vb destroys this open reading frame. In both cases, RFP is expressed and serves as a control for non–splicing-related effects. The start codons used are indicated as dots.