PUBLICATION

Mitogenic action of hypoxia upon cutaneous neuroepithelial cells in developing zebrafish

Authors
Dean, B.W., Rashid, T.J., Jonz, M.G.
ID
ZDB-PUB-161203-5
Date
2017
Source
Developmental Neurobiology   77(6): 789-801 (Journal)
Registered Authors
Dean, Benjamin, Jonz, Michael G.
Keywords
BrdU, Neuroepithelial cells, hypoxia, mitosis, serotonin
MeSH Terms
  • Animals
  • Bromodeoxyuridine/metabolism
  • Embryo, Nonmammalian
  • Hypoxia/physiopathology*
  • Larva
  • Microscopy, Confocal
  • Neuroepithelial Cells/metabolism*
  • Serotonin/metabolism
  • Skin/cytology*
  • Zebrafish*/anatomy & histology
  • Zebrafish*/embryology
  • Zebrafish*/growth & development
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism
PubMed
27907267 Full text @ Dev. Neurobiol.
Abstract
In zebrafish, cutaneous neuroepithelial cells (NECs) contain serotonin (5-HT) and are believed to initiate physiological and behavioral responses to hypoxia during embryonic and early larval development, when mature gills and O2 chemoreceptors are not yet present. The number of skin NECs rapidly declines as embryos develop into larvae, but acclimation to hypoxia leads to retention of a greater number of these cells. We hypothesized that reduction of the partial pressure of oxygen (PO2 ) in water would stimulate mitosis in cutaneous NECs in zebrafish. Zebrafish were exposed to 5-bromo-2'-deoxyuridine (BrdU) and immunolabeled with antibodies against serotonin and BrdU to identify mitotic skin cells, including NECs. Cells were imaged and quantified using confocal microscopy. From embryonic to larval stages, we observed an overall increase in the number of BrdU-positive cells in the skin, but a decrease in BrdU-positive serotonergic NECs. Exposure of larvae to hypoxia (PO2  = 30 mmHg) in vivo for 24 h produced a 1.7-fold increase in the number of NECs labeled with BrdU. We conclude that under normal environmental PO2 the population of cutaneous NECs declines due to a decrease in mitotic activity. During environmental hypoxia, the number of NECs undergoing cell division in the skin is increased, and this promotes retention of NECs under these conditions. These data demonstrate the direct action of hypoxia upon the cell cycle of cutaneous NECs in developing zebrafish, and support the notion that cutaneous NECs are embryonic O2 chemoreceptors. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 77: 789-801, 2017.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping