Functional expression and analysis of the pancreatic transcription factor PDX-1 in yeast.
The pancreas-specific transcription factor Pdx-1 is important for pancreas development and beta-cell specific gene expression in insulin-producing cells. We have expressed the mouse PDX-1 gene in the yeast Saccharomyces cerevisiae and characterized its functional domains. Pdx-1 functions as a strong activator in yeast and stimulates gene expression by more than 80-fold. The transcriptional activation domain of Pdx-1 is located within the first 144 amino-terminal amino acids. Pdx-1 is also able to bind and activate transcription from the A3 element of the human insulin gene promoter in yeast. Analysis of the effects of two-point mutations (Q59L and R197H) in the PDX-1 gene found in type II diabetes patients showed that both point mutations interfere with the ability of Pdx-1 to bind to DNA and to activate transcription in yeast.
Ozcan
Sabire
S
Department of Molecular and Cellular Biochemistry, Chandler Medical Center, University of Kentucky, 800 Rose Street, Lexington 40536, USA. sozcan@pop.uky.edu
Mosley
Amber L
AL
Aryal
Bishwa K
BK
D000818:Animals; D001120:Arginine / Q000737:chemistry; D015153:Blotting, Western; D017353:Gene Deletion; D005973:Glutamine / Q000737:chemistry; D018398:Homeodomain Proteins; D006801:Humans; D007328:Insulin / Q000235:genetics; D051379:Mice; D008957:Models, Genetic; D016296:Mutagenesis; D009154:Mutation; D010179:Pancreas / Q000378:metabolism*; D010957:Plasmids / Q000378:metabolism; D017354:Point Mutation; D011401:Promoter Regions, Genetic; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013997:Time Factors; D015534:Trans-Activators / Q000378:metabolism*; D014158:Transcription, Genetic; D001616:beta-Galactosidase / Q000378:metabolism
D018398:Homeodomain Proteins; D007328:Insulin; D015534:Trans-Activators; C084010:pancreatic and duodenal homeobox 1 protein; D005973:Glutamine; D001120:Arginine; D001616:beta-Galactosidase