ZFIN ID: ZDB-PUB-001205-4
Notch signalling and the synchronization of the somite segmentation clock
Jiang, Y.J., Aerne, B.L., Smithers, L., Haddon, C., Ish-Horowicz, D., and Lewis, J.
Date: 2000
Source: Nature   408(6811): 475-479 (Journal)
Registered Authors: Aerne, Birgit, Haddon, Catherine, Jiang, Yun-Jin, Lewis, Julian
Keywords: none
MeSH Terms:
  • Animals
  • Body Patterning/genetics
  • Body Patterning/physiology*
  • Embryo, Nonmammalian/cytology
  • Embryo, Nonmammalian/physiology
  • Embryonic Development
  • Intracellular Signaling Peptides and Proteins
  • Ligands
  • Membrane Proteins/biosynthesis
  • Membrane Proteins/physiology*
  • Mesoderm/physiology
  • Mutation
  • Receptors, Notch
  • Signal Transduction*
  • Somites/physiology
  • Zebrafish
PubMed: 11100729 Full text @ Nature
In vertebrates with mutations in the Notch cell-cell communication pathway, segmentation fails: the boundaries demarcating somites, the segments of the embryonic body axis, are absent or irregular. This phenotype has prompted many investigations, but the role of Notch signalling in somitogenesis remains mysterious. Somite patterning is thought to be governed by a "clock-and-wavefront" mechanism: a biochemical oscillator (the segmentation clock) operates in the cells of the presomitic mesoderm, the immature tissue from which the somites are sequentially produced, and a wavefront of maturation sweeps back through this tissue, arresting oscillation and initiating somite differentiation. Cells arrested in different phases of their cycle express different genes, defining the spatially periodic pattern of somites and controlling the physical process of segmentation. Notch signalling, one might think, must be necessary for oscillation, or to organize subsequent events that create the somite boundaries. Here we analyse a set of zebrafish mutants and arrive at a different interpretation: the essential function of Notch signalling in somite segmentation is to keep the oscillations of neighbouring presomitic mesoderm cells synchronized.