Role of hepatocyte nuclear factor 1alpha and 1beta in the transcriptional regulation of human dipeptidyl peptidase IV during differentiation of Caco-2 cells.
Caco-2 cells undergo differentiation to an enterocytic-like cell when maintained in a post-confluent state for 1-2 weeks. During this period Caco-2 cells begin to express high levels brush border membrane associated enzymes such as dipeptidyl peptidase IV. Using the dipeptidyl peptidase IV gene promoter in electrophoretic mobility shift assays, we have shown for the first time that levels of hepatocyte nuclear factor 1alpha increase three- to fourfold during Caco-2 cell differentiation. Transient cotransfection experiments with 3T3 cells using dipeptidyl peptidase IV promoter constructs and expression vectors containing hepatocyte nuclear factor 1alpha and beta show that the ratio of alpha and beta modulates reporter gene expression. These results suggest that the increase in levels of hepatocyte nuclear factor 1alpha that occur during intestinal cell differentiation, are important for expression of dipeptidyl peptidase IV and other intestinal proteins.
Erickson
R H
RH
Gastrointestinal Research Laboratory, Department of Veterans Affairs Medical Center, San Francisco, California 94121, USA. neko@itsa.ucsf.edu
Lai
R S
RS
Kim
Y S
YS
D018938:Caco-2 Cells; D002454:Cell Differentiation; D003110:Colonic Neoplasms / Q000201:enzymology* / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism; D018819:Dipeptidyl Peptidase 4 / Q000096:biosynthesis / Q000235:genetics*; D020895:Enterocytes / Q000166:cytology / Q000201:enzymology*; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D051537:Hepatocyte Nuclear Factor 1; D051538:Hepatocyte Nuclear Factor 1-alpha; D051539:Hepatocyte Nuclear Factor 1-beta; D006801:Humans; D007421:Intestine, Small / Q000166:cytology / Q000201:enzymology*; D008871:Microvilli / Q000201:enzymology; D009687:Nuclear Proteins; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; C496487:HNF1A protein, human; C496495:HNF1B protein, human; D051538:Hepatocyte Nuclear Factor 1-alpha; D009687:Nuclear Proteins; D014157:Transcription Factors; D051537:Hepatocyte Nuclear Factor 1; D051539:Hepatocyte Nuclear Factor 1-beta; D018819:Dipeptidyl Peptidase 4