PUBLICATION

Kinesin-1 promotes chondrocyte maintenance during skeletal morphogenesis

Authors
Santos-Ledo, A., Garcia-Macia, M., Campbell, P.D., Gronska, M., Marlow, F.L.
ID
ZDB-PUB-170718-1
Date
2017
Source
PLoS Genetics   13: e1006918 (Journal)
Registered Authors
Campbell, Philip, Marlow, Florence
Keywords
Chondrocytes, Cartilage, Embryos, Secretion, Autophagic cell death, Phenotypes, Lysosomes, Zebrafish
MeSH Terms
  • Animals
  • Cartilage/growth & development*
  • Cell Differentiation
  • Chondrocytes
  • Gene Expression Regulation, Developmental*
  • Kinesins/genetics
  • Kinesins/metabolism*
  • Morphogenesis
  • Osteogenesis*
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish/metabolism
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
PubMed
28715414 Full text @ PLoS Genet.
Abstract
During skeletal morphogenesis diverse mechanisms are used to support bone formation. This can be seen in the bones that require a cartilage template for their development. In mammals the cartilage template is removed, but in zebrafish the cartilage template persists and the bone mineralizes around the cartilage scaffold. Remodeling of unmineralized cartilage occurs via planar cell polarity (PCP) mediated cell rearrangements that contribute to lengthening of elements; however, the mechanisms that maintain the chondrocyte template that supports perichondral ossification remain unclear. We report double mutants disrupting two zebrafish kinesin-I genes (hereafter kif5Blof) that we generated using CRISPR/Cas9 mutagenesis. We show that zygotic Kif5Bs have a conserved function in maintaining muscle integrity, and are required for cartilage remodeling and maintenance during craniofacial morphogenesis by a PCP-distinct mechanism. Further, kif5Blof does not activate ER stress response genes, but instead disrupts lysosomal function, matrix secretion, and causes deregulated autophagic markers and eventual chondrocyte apoptosis. Ultrastructural and transplantation analysis reveal neighboring cells engulfing extruded kif5Blof chondrocytes. Initial cartilage specification is intact; however, during remodeling, kif5Blof chondrocytes die and the cartilage matrix devoid of hypertrophic chondrocytes remains and impedes normal ossification. Chimeric and mosaic analyses indicate that Kif5B functions cell-autonomously in secretion, nuclear position, cell elongation and maintenance of hypertrophic chondrocytes. Interestingly, large groups of wild-type cells can support elongation of neighboring mutant cells. Finally, mosaic expression of kif5Ba, but not kif5Aa in cartilage rescues the chondrocyte phenotype, further supporting a specific requirement for Kif5B. Cumulatively, we show essential Kif5B functions in promoting cartilage remodeling and chondrocyte maintenance during zebrafish craniofacial morphogenesis.
Errata / Notes
This article is corrected by ZDB-PUB-220906-86 .
Genes / Markers
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Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping