The homeodomain protein Cdx2 regulates lactase gene promoter activity during enterocyte differentiation

摘要: Abstract Background & Aims: Lactase is the intestinal disaccharidase responsible for digestion of lactose, predominant carbohydrate in milk. Transcription lactase gene activated during enterocyte differentiation. We have characterized interaction between promoter and Cdx2, a homeodomain protein involved regulating development Methods: Nuclear bound to cis element, CE-LPH1, was analyzed by electrophoretic mobility shift assays supershifts with Cdx2 antibody. activities were assayed cells transfected luciferase reporter constructs expression construct. Results: Electrophoretic assay CE-LPH1 yields specific DNA/protein complex that requires caudal-related binding site, TTTAC. The recognized antibody more abundant differentiated enterocytes. A construct able activate transcription driven wild-type, but not mutated, results increased endogenous messenger RNA. Conclusions: interacts capable activating gene. In contrast previous report, correlates These conclusions are consistent role cell GASTROENTEROLOGY 2000;118:115-127