Regulation of primitive hematopoiesis in zebrafish embryos by the death receptor gene

Kwan, T.T., Liang, R., Verfaillie, C.M., Ekker, S.C., Chan, L.C., Lin, S., and Leung, A.Y.
Experimental hematology   34(1): 27-34 (Journal)
Registered Authors
Ekker, Stephen C., Leung, Anskar, Lin, Shuo
MeSH Terms
  • Animals
  • Apoptosis/drug effects
  • Caspase 3
  • Caspases/drug effects
  • Caspases/metabolism
  • Disease Models, Animal
  • Embryo, Nonmammalian
  • Gene Expression Regulation, Developmental/drug effects
  • Glycoproteins/administration & dosage
  • Hematopoiesis/drug effects
  • Hematopoiesis/genetics
  • Hematopoiesis/physiology*
  • Hemoglobins/biosynthesis
  • Hemoglobins/drug effects
  • Intercellular Signaling Peptides and Proteins/administration & dosage
  • Morpholines/administration & dosage
  • Receptors, Tumor Necrosis Factor/administration & dosage*
  • Receptors, Tumor Necrosis Factor/genetics*
  • Receptors, Tumor Necrosis Factor/metabolism
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish/metabolism*
16413388 Full text @ Exp. Hematol.
OBJECTIVE: We investigated the regulatory mechanism of primitive hematopoiesis in zebrafish (Danio rerio) embryos with particular reference to the role of a death receptor (zDR) gene, based on a morpholino (MO) knockdown approach. METHODS: MOs targeting the zDR and chordin (Chd) were injected into naturally spawned embryos at one- to four-cell stage. A random sequence (RS) MO was used as a control. Effects on hemoglobin formation (Hb), apoptosis, and lineage-specific gene expression were examined. Embryos injected with zDR, Chd, and RS-MOs were denoted zDR(mo), zChd(mo), and zRS(mo), respectively. Those coinjected with Chd+zDR-MOs and Chd+RS-MOs were abbreviated zChd+DR(mo) and zChd+RS(mo). RESULTS: zDR mRNA expression was restricted to the intermediate cell mass of wild-type (WT) and zChd(mo) embryos. At 48 hours postfertilization, zDR(mo) embryos showed increased Hb compared with WT or zRS(mo) embryos (2.36 x 10(-2) +/- 1.13 x 10(-3) vs 1.85 x 10(-2) +/- 5.60 x 10(-4) vs 1.79 x 10(-2) +/- 1.31 x 10(-3) U, p < 0.05). zChd+DR(mo) embryos also showed increased Hb compared with zChd(mo) or zChd+RS(mo) embryos (4.60 x 10(-2) +/- 2.79 x 10(-3) vs 3.17 x 10(-2) +/- 1.07 x 10(-3) vs 3.05 x 10(-2) +/- 1.25 x 10(-3) U, p < 0.05). zDR-MO reduced apoptosis, as shown by reduced terminal transferase-mediated dUTP nick end-labeling staining in zChd+DR(mo) compared with zChd+RS(mo) embryos and caspase-3 activity in zDR(mo) vs zRS(mo) (0.525 +/- 0.094 vs 0.953 +/- 0.113 U, p < 0.05), and zChd+DR(mo) vs zChd+RS(mo) embryos (0.247 +/- 0.121 vs 1.180 +/- 0.082, p < 0.05). zChd+DR(mo) embryos showed upregulation of erythroid-specific embryonic hemoglobin gene expression but not that of a myeloid-specific myeloperoxidase gene. CONCLUSION: Knockdown of zDR in zebrafish embryos decreased apoptosis and increased Hb, suggesting that zDR may regulate primitive hematopoiesis during development.
Genes / Markers
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Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Engineered Foreign Genes