Figure 2

A transposable-element-insertion mutant of DFsn. (a) The gene structure of DFsn. The black-arrowed boxes indicate exons. A piggyBac transposable element, P(f06595) (represented by a big triangle), inserts in the second exon, 121 base-pairs upstream of the start codon (indicated by the red arrow). The red arrowhead points to the stop codon. Green arrows mark forward or reverse primers used in the PCR experiments described in (b, c). (b) PCR reactions using the indicated primer pairs and genomic DNA of wild-type or DFsn^f06595/Df [P(f06595)/Df(2R)7872] flies demonstrate the location of the P-element insertion. (c) RT-PCRs were performed using total RNAs from wild-type, DFsn^f06595/Df or DFsn^f06595[P(f06595)/P(f06595)] flies and poly dT oligo primer for the reverse transcription reactions. PCR performed with the indicated primer pairs at 26 cycles are shown here. The normal transcript in the wild type (accessed by primer pairs AF and DF) is disrupted in the DFsn mutants. Additional cycles of PCR only revealed mis-spliced DFsn transcripts in the DFsn mutants. Transcripts of TBP (TATA box binding protein) and rp49 (ribosomal protein 49) are analyzed as internal control.