ZFIN ID: ZDB-PUB-170303-5
tomm22 Knockdown-Mediated Hepatocyte Damages Elicit Both the Formation of Hybrid Hepatocytes and Biliary Conversion to Hepatocytes in Zebrafish Larvae.
Wu, J., Choi, T.Y., Shin, D.
Date: 2017
Source: Gene Expression   17(3): 237-249 (Journal)
Registered Authors: Choi, Tae-Young, Shin, Donghun
Keywords: Liver regeneration, Macrophage, Oval cells, Liver progenitor cells
MeSH Terms:
  • Animals
  • Animals, Genetically Modified
  • Biliary Tract/metabolism*
  • Cell Death
  • Cell Proliferation
  • Gene Knockdown Techniques
  • Green Fluorescent Proteins/metabolism
  • Hepatocytes/cytology*
  • Larva
  • Liver/injuries
  • Liver/pathology
  • Liver/physiology*
  • Liver Regeneration*
  • Macrophages/cytology
  • Mitochondrial Membrane Transport Proteins/genetics*
  • Models, Animal
  • Oligonucleotides, Antisense/genetics
  • Organ Size
  • Signal Transduction
  • Wnt Proteins/metabolism
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish Proteins/genetics*
  • beta Catenin/metabolism
PubMed: 28251883 Full text @ Gene Expr.
The liver has a highly regenerative capacity. In the normal liver, hepatocytes proliferate to restore lost liver mass.However, when hepatocyte proliferation is impaired, biliary epithelial cells (BECs) activate and contribute to hepatocytes. We previously reported in zebrafish that upon severe hepatocyte ablation, BECs extensively contribute to regenerated hepatocytes. It was also speculated that BECdriven liver regeneration might occur in another zebrafish liver injury model in which temporary knockdown of the mitochondrial import gene tomm22 by morpholino antisense oligonucleotides (MO) induces hepatocyte death. Given the importance of multiple BEC-driven liver regeneration models for better elucidating the mechanisms underlying innate liver regeneration in the diseased liver, we hypothesized that BECs would contribute to hepatocytes in tomm22 MO-injected larvae. In this MO-based liver injury model, by tracing the lineage of BECs, we found that BECs significantly contributed to hepatocytes. Moreover, we found that surviving, pre-existing hepatocytes become BEC-hepatocyte hybrid cells in tomm22 MO-injected larvae. Intriguingly, both the inhibition of Wnt/β-catenin signaling and macrophage ablation suppressed the formation of the hybrid hepatocytes. This new liver injury model in which both hepatocytes and BECs contribute to regenerated hepatocytes will aid in better understanding the mechanisms of innate liver regeneration in the diseased liver.