Protein kinase C consists of a protein family which can be classified into two major groups: Ca(2+)-dependent conventional protein kinase C and Ca(2+)-independent novel protein kinase C (nPKC). Among eight known members of protein kinase C family, we found that nPKC eta (eta) isolated from cDNA library of mouse skin, is most abundant in epithelial tissues including skin and epithelia of digestive and respiratory tracts. These data suggest potential role of this isoform in growth, differentiation and carcinogenesis of epithelial tissues.