Figure 3

The exon trapping vector pSPL3 used to assay SNP function. (A) The pSPL3 vector contains SD (splice donor) and SA (splice acceptor) sites that operate as exons, and a functional intron, with transcription beginning following the SV40 promoter and ending at the LPAS (late poly (A) signal). Wild pSPL3-W and mutant pSPL3-M plasimds containing 914 bp of intron 8, exon 9 and 453 bp of intron 9 and harboring either the C or T alleles were separately cloned into the EcoRI and XhoI cloning sites of the pSPL3 vector. (B) Agarose gel electrophoresis of RT-PCR products. SD6 and SA2 primers were designed for RT-PCR amplification of cDNA sequences generated by transfected 293 T cells. Lane1: Marker;DNA Marker 600 (TIANGEN, China); Lane2: 263 bp; Lane3: 365 bp (263 bp + 54 bp + 48 bp) and 317 bp (263 bp + 54 bp); Lane 4: 317 bp (263 bp + 54 bp). MCS: multiple cloning sites.