claudin 6 overexpression disturbs the overall claudin distribution. claudin 6 overexpression disturbs the overall claudin distribution. (A,B) RT-PCR analysis of various claudins using RNA extracted from newborn epidermis revealed that the overexpression of claudin 6 resulted in modification of the expression profiles of other claudins in transgenic epidermis. Semi-quantitative RT-PCR analysis at 25, 30 and 35 cycles shows the range of signal detection between the epidermis of wild-type and Inv-Cldn6 transgenic mice. claudin 2 and 9 were undetectable in both samples. (C) Immunofluorescence analysis of transgenic and wild-type backskin samples supports the RT-PCR results, showing virtually no difference in claudin 1 staining and no claudin 2 detection. Labelling in the SC is due to non-specific binding of the secondary antibody. Kursad Turksen, and Tammy-Claire Troy Development 2002;129:1775-1784 © 2002.