Bile system morphogenesis defects and liver dysfunction upon targeted deletion of HNF1beta.
The inactivation of the Hnf1beta gene identified an essential role in epithelial differentiation of the visceral endoderm and resulted in early embryonic death. In the present study, we have specifically inactivated this gene in hepatocytes and bile duct cells using the Cre/loxP system. Mutant animals exhibited severe jaundice caused by abnormalities of the gallbladder and intrahepatic bile ducts (IHBD). The paucity of small IHBD was linked to a failure in the organization of duct structures during liver organogenesis, suggesting an essential function of Hnf1b in bile duct morphogenesis. Mutant mice also lacked interlobular arteries. As HNF1beta is not expressed in these cells, it further emphasizes the link between arterial and biliary formation. Hepatocyte metabolism was also affected and we identified hepatocyte-specific HNF1beta target genes involved in bile acids sensing and in fatty acid oxidation.
Coffinier
Catherine
C
Unité des Virus Oncogènes-CNRS URA 1644, Institut Pasteur, 25, rue du Docteur Roux, 75724 Paris Cedex 15, France.
Gresh
Lionel
L
Fiette
Laurence
L
Tronche
François
F
Schütz
Günther
G
Babinet
Charles
C
Pontoglio
Marco
M
Yaniv
Moshe
M
Barra
Jacqueline
J
D044942:Acyl-CoA Dehydrogenase, Long-Chain; D000483:Alleles; D001647:Bile Acids and Salts / Q000378:metabolism; D001652:Bile Ducts / Q000002:abnormalities / Q000196:embryology*; D001653:Bile Ducts, Intrahepatic / Q000002:abnormalities / Q000196:embryology; D001663:Bilirubin / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D004847:Epithelial Cells; D044943:Fatty Acid Desaturases / Q000235:genetics; D005704:Gallbladder / Q000002:abnormalities / Q000196:embryology; D018390:Gene Targeting; D051539:Hepatocyte Nuclear Factor 1-beta; D007565:Jaundice; D050356:Lipid Metabolism; D008099:Liver / Q000503:physiopathology*; D009024:Morphogenesis; D016296:Mutagenesis; D029362:Organic Anion Transporters, Sodium-Independent / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014280:Triglycerides / Q000378:metabolism
D001647:Bile Acids and Salts; D004268:DNA-Binding Proteins; D029362:Organic Anion Transporters, Sodium-Independent; C421102:Slco1a1 protein, rat; D014157:Transcription Factors; D014280:Triglycerides; D051539:Hepatocyte Nuclear Factor 1-beta; D002784:Cholesterol; D044943:Fatty Acid Desaturases; D044942:Acyl-CoA Dehydrogenase, Long-Chain; D001663:Bilirubin