Figure 1

Generation and characterization of Cx43KI26 mice. (A) pCx43KI26 vector DNA was transfected into HM-1 embryonic stem cells. Homologous recombination was tested by PCR and Southern blot analyses. Homozygously recombined clones were injected into blastocysts of C57BL/6 mice, in order to generate first chimeras and in the next generation of mice carrying the Cx43KI26neo allele. By means of Flp activity, the frt-flanked selection cassette was deleted, resulting in the Cx43KI26 allele. In mice carrying this allele, Cx26 is expressed under control of Cx43 regulatory elements. (B) Multiplex PCR of different genotypes using primer 1 (Cx43-RO4), primer 2 (Ki26Cx26) and primer 3 (Cx43-HO2). A 381 bp amplicon indicates the wild type Cx43 allele and a 529 bp fragment the Ca43KI26 allele. The middle lane represents the heterozygous genotype Cx43^43/26. (C) Southern blot analysis of PstI digested Cx43^43/43, Cx43^43/26 and Cx43^26/26 DNA using the external Cx43 probe. A 8 kb fragment is indicative of the Cx43 wild-type allele, whereas a 3.5 kb fragment represents the Cx43KI26 allele.