ZFIN ID: ZDB-PUB-070813-30
Control of morphogenetic cell movements in the early zebrafish myotome
Daggett, D.F., Domingo, C.R., Currie, P.D., and Amacher, S.L.
Date: 2007
Source: Developmental Biology   309(2): 169-179 (Journal)
Registered Authors: Amacher, Sharon, Currie, Peter D., Daggett, Dave
Keywords: Myotome, Muscle, cap, Adaxial, Apical constriction, Somite, Zebrafish
MeSH Terms:
  • Animals
  • Body Patterning
  • Carrier Proteins/metabolism*
  • Cell Movement
  • Gene Expression Regulation, Developmental
  • Muscle Cells/physiology*
  • Mutation
  • Notochord/physiology
  • Somites/physiology
  • Zebrafish/embryology
  • Zebrafish/physiology*
  • Zebrafish Proteins/metabolism*
PubMed: 17689522 Full text @ Dev. Biol.
As the vertebrate myotome is generated, myogenic precursor cells undergo extensive and coordinated movements as they differentiate into properly positioned embryonic muscle fibers. In the zebrafish, the "adaxial" cells adjacent to the notochord are the first muscle precursors to be specified. After initially differentiating into slow-twitch myosin-expressing muscle fibers, these cells have been shown to undergo a remarkable radial migration through the lateral somite, to populate the superficial layer of slow-twitch muscle of the mature myotome. Here we characterize an earlier set of adaxial cell behaviors; the transition from a roughly 4x5 array of cuboidal cells to a 1x20 stack of elongated cells, prior to the migration event. We find that adaxial cells display a highly stereotypical series of behaviors as they undergo this rearrangement. Furthermore, we show that the actin regulatory molecule, Cap1, is specifically expressed in adaxial cells and is required for the progression of these behaviors. The requirement of Cap1 for a cellular apical constriction step is reminiscent of similar requirements of Cap during apical constriction in Drosophila development, suggesting a conservation of gene function for a cell biological event critical to many developmental processes.