Zebrafishvps33b, an ortholog of the gene responsible for human arthrogryposis-renal dysfunction-cholestasis syndrome, regulates biliary development downstream of the onecut transcription factorhnf6

Abstract

SummaryZebrafish vps33b, an ortholog of the gene responsible for human arthrogryposis-renal dysfunction-cholestasis syndrome, regulates biliary development downstream of the onecut transcription factor hnf6

Transcription factor onecut3 regulates intrahepatic biliary development in zebrafish

“…This keratin pattern resembled the ectopic cytokeratin expression observed in hepatocytes of Hnf6-deficient mice (Clotman et al, 2002) and is also present in the livers of zebrafish larvae at the onset of biliary development ( Fig. 3L; see also Lorent et al, 2004;Matthews et al, 2004Matthews et al, , 2005. Since hepatocytes are the principal non-biliary cells in the 5-dpf zebrafish liver, it is likely that the non-biliary immunoreactive keratin is present in these cells (as reported for Hnf6-deficient mice).…”

“…The morpholinos targeted the translation initiation codon or the splice acceptor of the second exon of the oc3 gene (Table 1). To measure the effect of the knockdowns on biliary development, we examined intrahepatic bile duct anatomy and biliary secretion, as determined by gallbladder fluorescence following ingestion of PED6, a fluorescent phospholipid (Farber et al, 2001;Matthews et al, 2004Matthews et al, , 2005. Keratin immunohistochemistry, which delineates bile ducts in zebrafish larvae Matthews et al, , 2005, demonstrated altered duct morphology in over 95% of 5-dpf morpholino-injected larvae analyzed ( Fig.…”

“…Sequences of the oc3 morpholinos are in Table 1, while those for hnf6 have been published previously . Morpholinos were injected at the one-cell stage at an amounts of 2-4 pmol, as performed previously for other morpholinos directed against genes involved in biliary development Matthews et al, 2004Matthews et al, , 2005. All injections were performed on wild-type TLF (Tü bingen Long-Fin) strain zebrafish (Danio rerio) maintained in standard conditions and in accordance with the Institutional Animal Care and Use Committee of the University of Pennsylvania.…”

Three-dimensional structural analysis reveals a Cdk5-mediated kinase cascade regulating hepatic biliary network branching in zebrafish

“…In zebrafish, the intrahepatic biliary network is formed by small-diameter ductular biliary epithelial cells, which might be analogous to small-diameter ductular biliary epithelial cells in the mammalian liver lobule that transport bile from the canalicular network to the intralobular bile ducts in the portral tract (Kaneko et al, 2015). Indeed, there is remarkable conservation of both genes and gene function across vertebrate biliary system development, and thus many candidate genes responsible for biliary system abnormalities in humans can be screened efficiently and rapidly in the zebrafish model Delous et al, 2012;Hand et al, 2009;Lorent et al, 2015Lorent et al, , 2010Lorent et al, , 2004Matthews et al, 2011Matthews et al, , 2005Sakaguchi et al, 2008;Schaub et al, 2012). The zebrafish transgenic line Tg(Tp1-MmHbb: EGFP) um14 , which is generated by conjugating tandem RBPJκ response element repeats with enhanced green fluorescent protein (EGFP), expresses EGFP specifically in the intrahepatic biliary network in the zebrafish liver (Lorent et al, 2010;Parsons et al, 2009).…”

Analysis of the Zebrafish Proteome during Embryonic Development

“…Many mutant phenotypes are reminiscent of human disease and have proved invaluable in deciphering signaling cascades implicated in cardiovascular (3,19), renal (20), and gastrointestinal biology (21) and in cancer (22). Initial forward genetic screens have phenotyped embryos based on morphology as optical clarity during external zebrafish embryogenesis facilitates visual analysis during their rapid development (6).…”