PUBLICATION

Autonomous onset of the circadian clock in the zebrafish embryo

Authors
Dekens, M.P., and Whitmore, D.
ID
ZDB-PUB-080922-16
Date
2008
Source
The EMBO journal   27(20): 2757-2765 (Journal)
Registered Authors
Dekens, Marcus P.S., Whitmore, David
Keywords
bmal, circadian clock, clock, ontogeny, period
MeSH Terms
  • ARNTL Transcription Factors
  • Animals
  • Basic Helix-Loop-Helix Transcription Factors/metabolism
  • CLOCK Proteins
  • Circadian Rhythm*
  • Gene Expression Regulation, Developmental*
  • Light
  • Models, Biological
  • Models, Genetic
  • Oscillometry
  • Temperature
  • Time Factors
  • Trans-Activators/metabolism
  • Transcription Factors/metabolism
  • Transcription, Genetic
  • Zebrafish
  • Zebrafish Proteins/metabolism
PubMed
18800057 Full text @ EMBO J.
Abstract
On the first day of development a circadian clock becomes functional in the zebrafish embryo. How this oscillator is set in motion remains unclear. We demonstrate that zygotic period1 transcription begins independent of light exposure. Pooled embryos maintained in darkness and under constant temperature show elevated non-oscillating levels of period1 expression. Consequently, there is no maternal effect or developmental event that sets the phase of the circadian clock. Analysis of period1 transcription, at the cellular level in the absence of environmental stimuli, reveals oscillations in cells that are asynchronous within the embryo. Demonstrating an autonomous onset to rhythmic period1 expression. Transcription of clock1 and bmal1 is rhythmic in the adult, but constant during development in light-entrained embryos. Transient expression of dominant-negative DeltaCLOCK blocks period1 transcription, thus showing that endogenous CLOCK is essential for the transcriptional regulation of period1 in the embryo. We demonstrate a default mechanism in the embryo that initiates the autonomous onset of the circadian clock. This embryonic clock is differentially regulated from that in the adult, the transition coinciding with the appearance of several clock output processes.
Genes / Markers
Figures
Show all Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping