Demonstration of the pathogenic effect of point mutated keratin 9 in vivo

A wild type keratin 9 (K9) cDNA and a point mutated keratin 9 cDNA mere inj ected subcutaneously into mouse skin. The hemagglutinin tag staining of the wild type K9 cDNA injected specimens mainly showed a homogeneous pattern, whereas the point mutated K9 cDNA injected specimens mainly showed a granul ar pattern in the suprabasal cells. Double staining of K9 and the endogenou s keratin revealed the incorporation of de novo synthesized K9 into the ker atin network. These results demonstrate that (1) a naked DNA transfection i nto mouse skin can detect the pathogenic changes of point mutated keratin i n vivo and (2) the keratin 9 mutation disrupts the keratin network formatio n in the suprabasal cells in vivo. (C) 1999 Federation of European Biochemi cal Societies.