title: A novel keratin18 promoter that drives reporter gene expression in the intrahepatic and extrahepatic biliary system allows isolation of cell-type specific transcripts from zebrafish liver.
abstract: Heritable and acquired biliary disorders are an important cause of acute and chronic human liver disease. Biliary development and physiology have been studied extensively in rodent models and more recently, zebrafish have been used to uncover pathogenic mechanisms and potential therapies for these conditions. Here we report development of novel transgenic lines labeling the intrahepatic and extrahepatic biliary system of zebrafish larvae that can be used for lineage tracing and isolation of biliary-specific RNAs from mixed populations of liver cells. We show that GFP expression driven by a 4.4 kilobase promoter fragment from the zebrafish keratin18 (krt18) gene allows visualization of all components of the developing biliary system as early as 3 days post-fertilization. In addition, expression of a ribosomal fusion protein (EGFP-Rpl10a) in krt18:TRAP transgenic fish allows for enrichment of translated biliary cell mRNAs via translating ribosome affinity purification (TRAP). Future studies utilizing these reagents will enhance our understanding of the morphologic and molecular processes involved in biliary development and disease.
authors.affiliation: Division of Anatomic Pathology, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Wilkins
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA 19104, USA.
authors.forename: Weilong
authors.initials: W
authors.lastname: Gong
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA 19104, USA. Electronic address: mpack@mail.med.upenn.edu.
authors.forename: Michael
authors.initials: M
authors.lastname: Pack
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001652:Bile Ducts / Q000201:enzymology / Q000378:metabolism*; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D022781:Hepatocytes / Q000378:metabolism; D053538:Keratin-18 / Q000235:genetics*; D008099:Liver / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D015027:Zebrafish / Q000196:embryology / Q000235:genetics*; D029961:Zebrafish Proteins / Q000235:genetics*
chemical_list: D053538:Keratin-18; D029961:Zebrafish Proteins; C479873:krt18a.1 protein, zebrafish
keywords: Gallbladder; Gene profiling; Liver; Translation