To continue the characterization of pancreatic gene expression, the applicant proposes a analysis of the transcriptional control of pancreatic development: The investigator will test the role of the key pancreatic acinar transcription factor PTF1 in pancreogenesis. The acinar cell-specific transcription of the pancreatic elastase I (EI) gene provides a simple paradigm of transcriptional regulation during organogenesis. Transcription is controlled by three elements (A, B and C) within a tissue- specific enhancer that specifies the level and pancreas-specificity of transcription. A repressor region immediately upstream of the enhancer restricts expression to the acinar cells. The A element binds an acinar cell- specific transcription factor (PTF1) and is the sole positively acting element that directs acinar cell-specific transcription of the other acinar cell- specific genes as well. The investigator proposes that PTF1 plays a pleiotropic role in the embryonic development of the exocrine pancreas. Cloning the genes for one or more PTF1 subunits, followed by creation and analysis of PTF1-deficient homozygous mice will test the role of PTF1 in exocrine gene transcription and in pancreatic organ formation.
Viswanath, R L; Rose, S D; Swift, G H et al. (2000) A binary mechanism for the selective action of a pancreatic beta -cell transcriptional silencer. J Biol Chem 275:40273-81 |
Swift, G H; Liu, Y; Rose, S D et al. (1998) An endocrine-exocrine switch in the activity of the pancreatic homeodomain protein PDX1 through formation of a trimeric complex with PBX1b and MRG1 (MEIS2). Mol Cell Biol 18:5109-20 |
MacDonald, R J; Swift, G H (1998) Analysis of transcriptional regulatory regions in vivo. Int J Dev Biol 42:983-94 |
Kruse, F; Komro, C T; Michnoff, C H et al. (1988) The cell-specific elastase I enhancer comprises two domains. Mol Cell Biol 8:893-902 |
Davis, B P; MacDonald, R J (1988) Limited transcription of rat elastase I transgene repeats in transgenic mice. Genes Dev 2:13-22 |