The cut-homeodomain transcriptional activator HNF-6 is coexpressed with its target gene HNF-3β in the developing murine liver and pancreas

摘要: Abstract Murine hepatocyte nuclear factor-3β (HNF-3β) protein is a member of large family developmentally regulated transcription factors that share homology in the winged helix/fork headDNA binding domain and participate embryonic pattern formation. HNF-3β also mediates cell-specific genes important for function hepatocytes, intestinal bronchiolar epithelial, pancreatic acinar cells. We have previously identified liver-enriched factor, HNF-6, which required promoter activity recognizes regulatory region numerous hepatocyte-specific genes. In this study we used yeast one-hybrid system to isolate HNF-6 cDNA, encodes cut-homeodomain-containing factor binds with same specificity as liver protein. Cotransfection assays demonstrate activates expression reporter gene driven by site from either or transthyretin (TTR) regions. interspecific backcross analysis determine murineHnf6gene located middle mouse chromosome 9.In situhybridization studies staged specific embryos its potential target gene, HNF-3β, are coexpressed hepatic diverticulum. More detailed HNF-3β's developmental patterns provides evidence colocalization ductal epithelial exocrine The these two do not overlap other endoderm-derived tissues neurotube. found abundantly expressed dorsal root ganglia, marginal layer, midbrain. At day 18 gestation adult pancreas, transcripts colocalize cells, but their diverge epithelium. continues epithelium, whereas only becomes restricted endocrine cells islets Langerhans. discuss respect specification hepatocytes differentiation pancreas.