PUBLICATION

Loss of Dnmt1 catalytic activity reveals multiple roles for DNA methylation during pancreas development and regeneration

Authors
Anderson, R.M., Bosch, J.A., Goll, M.G., Hesselson, D., Dong, P.D., Shin, D., Chi, N.C., Shin, C.H., Schlegel, A., Halpern, M., and Stainier, D.Y.
ID
ZDB-PUB-090731-2
Date
2009
Source
Developmental Biology   334(1): 213-223 (Journal)
Registered Authors
Anderson, Ryan, Chi, Neil C., Dong, P. Duc, Goll, Mary, Halpern, Marnie E., Hesselson, Daniel, Schlegel, Amnon, Shin, Chong, Shin, Donghun, Stainier, Didier
Keywords
Methylation, Dnmt1, Pancreas, Epigenetics, Regeneration, Zebrafish, ENU mutagenesis, Mutant, Beta cells, Liver
MeSH Terms
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cell Survival
  • DNA (Cytosine-5-)-Methyltransferases/genetics*
  • DNA (Cytosine-5-)-Methyltransferases/metabolism
  • DNA Methylation
  • Endocrine Cells/metabolism
  • Fluorescent Antibody Technique
  • Insulin-Secreting Cells/cytology
  • Insulin-Secreting Cells/metabolism
  • Molecular Sequence Data
  • Pancreas/cytology*
  • Pancreas/growth & development
  • Regeneration/physiology*
  • Zebrafish/metabolism
  • Zebrafish Proteins/genetics*
  • Zebrafish Proteins/metabolism
PubMed
19631206 Full text @ Dev. Biol.
Abstract
Developmental mechanisms regulating gene expression and the stable acquisition of cell fate direct cytodifferentiation during organogenesis. Moreover, it is likely that such mechanisms could be exploited to repair or regenerate damaged organs. DNA methyltransferases (Dnmts) are enzymes critical for epigenetic regulation, and are used in concert with histone methylation and acetylation to regulate gene expression and maintain genomic integrity and chromosome structure. We carried out two forward genetic screens for regulators of endodermal organ development. In the first, we screened for altered morphology of developing digestive organs, while in the second we screed for the lack of terminally differentiated cell types in the pancreas and liver. From these screens, we identified two mutant alleles of zebrafish dnmt1. Both lesions are predicted to eliminate dnmt1 function; one is a missense mutation in the catalytic domain and the other is a nonsense mutation that eliminates the catalytic domain. In zebrafish dnmt1 mutants, the pancreas and liver form normally, but begin to degenerate after 84 hours post fertilization (hpf). Acinar cells are nearly abolished through apoptosis by 100 hpf, though neither DNA replication, nor entry into mitosis are halted in the absence of detectable Dnmt1. However, endocrine cells and ducts are largely spared. Surprisingly, dnmt1 mutants and dnmt1 morpholino-injected larvae show increased capacity for pancreatic beta cell regeneration in an inducible model of pancreatic beta cell ablation. Thus, our data suggest that Dnmt1 is dispensable for pancreatic duct or endocrine cell formation, but not for acinar cell survival. In addition, Dnmt1 may influence the differentiation of pancreatic beta cell progenitors or the reprogramming of cells toward the pancreatic beta cell fate.
Genes / Markers
Figures
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Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping