FIG. 2.

Characterization of dsc1 transcripts in newborn epidermis of wild-type (WT) and homozygous mutant (MT; dsc1^{−/−ΔE17LoxP}) mice by RT-PCR. The 5′ primer was derived from the junction between exons 14 and 15, i.e., designed to suppress amplification of genomic DNA. The 3′ primer was derived from exon 16. (A) Agarose gel with RT-PCR products derived from three wild-type and three mutant samples. The PCR products were sequenced. The exon-intron organization of the product is schematically shown. (B) dsc1 gene structure and mRNA in wild-type and mutant mice. Note that exons 16 and 17 both contain stop codons. In mutant mice, we detected a single transcript that was aberrantly spliced, i.e., retained intron 15. DNA sequence analysis predicted that the mutant (MT) transcript encodes a protein in which the Dsc1b-specific sequence ESIRGHTLIKN is replaced by the sequence VSAQSSSAHSVQC. The sequence RLGE is encoded by the 3′ end of exon 15. Note that we have not confirmed the presence of the aberrant amino acid sequence at the COOH terminus of mutant Dsc1 by protein sequencing.