- The proximal promoter of the human transglutaminase 3 gene. Stratified squamous epithelial-specific expression in cultured cells is mediated by binding of Sp1 and ets transcription factors to a proximal promoter element. Lee, J.H., Jang, S.I., Yang, J.M., Markova, N.G., Steinert, P.M. J. Biol. Chem. (1996)