ZFIN ID: ZDB-PUB-180407-4
Segmentation of the zebrafish axial skeleton relies on notochord sheath cells and not on the segmentation clock
LLeras Forero, L., Narayanan, R., Huitema, L.F.A., VanBergen, M., Apschner, A., Peterson-Maduro, J., Logister, I., Valentin, G., Morelli, L.G., Oates, A., Schulte-Merker, S.
Date: 2018
Source: eLIFE   7: (Journal)
Registered Authors: Apschner, Alexander, Huitema, Leonie, Logister, Ive, Narayanan, Rachna, Oates, Andrew, Peterson-Maduroe, Josi, Schulte-Merker, Stefan
Keywords: developmental biology, stem cells, zebrafish
MeSH Terms:
  • Animals
  • Animals, Genetically Modified/embryology
  • Animals, Genetically Modified/genetics
  • Animals, Genetically Modified/physiology*
  • Biological Clocks*
  • Body Patterning*
  • Bone and Bones/embryology
  • Bone and Bones/physiology*
  • Embryo, Nonmammalian/cytology
  • Embryo, Nonmammalian/physiology
  • Gene Expression Regulation, Developmental
  • Mesoderm/embryology
  • Mesoderm/physiology
  • Mutation
  • Notochord/embryology
  • Notochord/physiology*
  • Pyrophosphatases/genetics
  • Pyrophosphatases/metabolism*
  • Zebrafish/embryology
  • Zebrafish/genetics
  • Zebrafish/physiology*
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
PubMed: 29624170 Full text @ Elife
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ABSTRACT
Segmentation of the axial skeleton in amniotes depends on the segmentation clock, which patterns the paraxial mesoderm and the sclerotome. While the segmentation clock clearly operates in teleosts, the role of the sclerotome in establishing the axial skeleton is unclear. We severely disrupt zebrafish paraxial segmentation, yet observe a largely normal segmentation process of the chordacentra. We demonstrate that axial entpd5+ notochord sheath cells are responsible for chordacentrum mineralization, and serve as a marker for axial segmentation. While autonomous within the notochord sheath, entpd5 expression and centrum formation show some plasticity and can respond to myotome pattern. These observations reveal for the first time the dynamics of notochord segmentation in a teleost, and are consistent with an autonomous patterning mechanism that is influenced, but not determined by adjacent paraxial mesoderm. This behavior is not consistent with a clock-type mechanism in the notochord.
ADDITIONAL INFORMATION