PUBLICATION

Knockdown of col22a1 gene in zebrafish induces a muscular dystrophy by disruption of the myotendinous junction

Authors
Charvet, B., Guiraud, A., Malbouyres, M., Zwolanek, D., Guillon, E., Bretaud, S., Monnot, C., Schulze, J., Bader, H.L., Allard, B., Koch, M., and Ruggiero, F.
ID
ZDB-PUB-131119-10
Date
2013
Source
Development (Cambridge, England)   140(22): 4602-4613 (Journal)
Registered Authors
Keywords
collagen, extracellular matrix, muscular dystrophy, myotendinous junction, skeletal muscle, zebrafish
MeSH Terms
  • Proto-Oncogene Proteins c-akt/metabolism
  • Cell Survival/drug effects
  • Phosphorylation/drug effects
  • Mammals
  • Animals
  • Collagen/genetics*
  • Collagen/metabolism
  • Muscular Dystrophy, Animal/embryology
  • Muscular Dystrophy, Animal/genetics
  • Muscular Dystrophy, Animal/pathology*
  • RNA, Messenger/genetics
  • RNA, Messenger/metabolism
  • Humans
  • Phenotype
  • Integrins/metabolism
  • Morpholinos/pharmacology
  • Embryo, Nonmammalian/drug effects
  • Embryo, Nonmammalian/metabolism
  • Embryo, Nonmammalian/ultrastructure
  • Extracellular Matrix/drug effects
  • Extracellular Matrix/metabolism
  • Fluorescent Antibody Technique
  • Microinjections
  • Tendons/drug effects
  • Tendons/metabolism
  • Tendons/pathology*
  • Tendons/ultrastructure
  • Sequence Homology, Amino Acid
  • Gene Knockdown Techniques*
  • Muscle Fibers, Skeletal/drug effects
  • Muscle Fibers, Skeletal/metabolism
  • Muscle Fibers, Skeletal/pathology
  • Zebrafish/genetics*
  • Muscle Weakness/metabolism
  • Muscle Weakness/pathology
(all 35)
PubMed
24131632 Full text @ Development
Abstract

The myotendinous junction (MTJ) is the major site of force transfer in skeletal muscle, and defects in its structure correlate with a subset of muscular dystrophies. Col22a1 encodes the MTJ component collagen XXII, the function of which remains unknown. Here, we have cloned and characterized the zebrafish col22a1 gene and conducted morpholino-based loss-of-function studies in developing embryos. We showed that col22a1 transcripts localize at muscle ends when the MTJ forms and that COLXXII protein integrates the junctional extracellular matrix. Knockdown of COLXXII expression resulted in muscular dystrophy-like phenotype, including swimming impairment, curvature of embryo trunk/tail, strong reduction of twitch-contraction amplitude and contraction-induced muscle fiber detachment, and provoked significant activation of the survival factor Akt. Electron microscopy and immunofluorescence studies revealed that absence of COLXXII caused a strong reduction of MTJ folds and defects in myoseptal structure. These defects resulted in reduced contractile force and susceptibility of junctional extracellular matrix to rupture when subjected to repeated mechanical stress. Co-injection of sub-phenotypic doses of morpholinos against col22a1 and genes of the major muscle linkage systems showed a synergistic gene interaction between col22a1 and itga7 (α7β1 integrin) that was not observed with dag1 (dystroglycan). Finally, pertinent to a conserved role in humans, the dystrophic phenotype was rescued by microinjection of recombinant human COLXXII. Our findings indicate that COLXXII contributes to the stabilization of myotendinous junctions and strengthens skeletal muscle attachments during contractile activity.

Genes / Markers
Figures
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Expression
Phenotype
Mutations / Transgenics
No data available
Human Disease / Model
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Sequence Targeting Reagents
Target Reagent Reagent Type
col22a1MO1-col22a1MRPHLNO
col22a1MO2-col22a1MRPHLNO
dag1MO1-dag1MRPHLNO
itga7MO1-itga7MRPHLNO
lama2MO1-lama2MRPHLNO
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Fish
Antibodies
Orthology
No data available
Engineered Foreign Genes
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Mapping
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