Figure 5.
Individual Pcdh-γ variable exons have their own promoters. (A) Identification of SNPs and RFLPs in variable exon B6 between 129S and CBA/J mouse strains. The relevant sequences from different mouse strains are shown as well as SspI RFLP analysis of genomic DNA from different mouse strains. (B) Targeting of a B6 transgene from the CBA/J strain into the Pcdh-γ locus in mouse ES cells (129S strain). The CBA/J B6 transgene consists of 2.5-kb 5′ flanking sequence, the coding exon and 2.1 kb of intronic sequence. This transgene is transcribed in the same orientation as the endogenous Pcdh-γ gene cluster. cDNA RFLP analysis revealed that the CBA/J-B6 exon was expressed at a level similar to the endogenous 129S-B6 exon (lanes 1,3). Wild-type ES cells serve as a control (lane 5). The RT (minus) control excludes the possibility of genomic DNA contamination.