Upregulation of interfollicular epidermal and hair infundibulum β-catenin expression in Gsdma3 mutant mice.

Skin hyperplasia associated with hair follicle abnormality can be seen in many skin diseases caused by gene mutations. Gsdma3 was reported to be a mutation hotpot gene whose mutation contributed to various skin hyperplasia phenotypes in Bsk, Dfl, Rco2, Fgn, Re (den), and Rim3 mice. However, the signaling molecules involved in these skin anomalies due to Gsdma3 mutations have not yet been addressed. In this study, using hematoxylin and eosin staining, we showed that Gsdma3 mutation gave rise to thickened skin and lengthened hair infundibula throughout the hair follicle cycle. Using immunofluoresence staining, we found that Gsdma3 had a spatial expression profile very similar to that of β-catenin in the epidermis and skin appendages. Furthermore, we showed that epidermal β-catenin expression was increased at all postnatal stages in Gsdma3 mutant mice. These results suggest that Gsdma3 may play a role in the proliferation and differentiation of epidermal cells and hair follicles through negatively regulating β-catenin expression.