The distribution and function of beta-catenin was investigated in involved psoriatic epidermis and in epidermal keratinocytes. Increased nuclear beta-catenin was seen in lesional psoriatic epidermis compared with nonlesional or normal skin. Transglutaminase 1 (TGase 1) expression overlapped with beta-catenin in lesional psoriatic skin and it was thought that beta-catenin and glycogen synthase kinase 3 beta may regulate TGase 1 expression (Hamptron, P.J. et al. Br J Dermatol 2007, 157(6); 1168-1177).