- Constitutive expression of the gene for the cell-specific p48 DNA-binding subunit of pancreas transcription factor 1 in cultured cells is under control of binding sites for transcription factors Sp1 and alphaCbf. Knöfler, M., Krapp, A., Hagenbüchle, O., Wellauer, P.K. J. Biol. Chem. (1996)