PUBLICATION

Inner Ear and Muscle Developmental Defects in Smpx-Deficient Zebrafish Embryos

Authors
Ghilardi, A., Diana, A., Bacchetta, R., Santo, N., Ascagni, M., Prosperi, L., Del Giacco, L.
ID
ZDB-PUB-210703-18
Date
2021
Source
International Journal of Molecular Sciences   22(12): (Journal)
Registered Authors
Del Giacco, Luca, Ghilardi, Anna, Prosperi, Laura
Keywords
SMPX, X-chromosome, hearing loss, myopathy, zebrafish
MeSH Terms
  • Animals
  • Ear, Inner/embryology*
  • Ear, Inner/metabolism*
  • Embryonic Development
  • Fluorescent Antibody Technique
  • Gene Expression Regulation, Developmental
  • Gene Knockdown Techniques
  • Hair Cells, Auditory/metabolism
  • Mechanotransduction, Cellular/genetics
  • Muscle Development/genetics
  • Muscle Proteins/deficiency*
  • Muscles/embryology*
  • Muscles/metabolism*
  • Organogenesis/genetics
  • Phenotype
  • Protein Transport
  • Zebrafish/embryology*
  • Zebrafish/genetics*
PubMed
34204426 Full text @ Int. J. Mol. Sci.
Abstract
The last decade has witnessed the identification of several families affected by hereditary non-syndromic hearing loss (NSHL) caused by mutations in the SMPX gene and the loss of function has been suggested as the underlying mechanism. In the attempt to confirm this hypothesis we generated an Smpx-deficient zebrafish model, pointing out its crucial role in proper inner ear development. Indeed, a marked decrease in the number of kinocilia together with structural alterations of the stereocilia and the kinocilium itself in the hair cells of the inner ear were observed. We also report the impairment of the mechanotransduction by the hair cells, making SMPX a potential key player in the construction of the machinery necessary for sound detection. This wealth of evidence provides the first possible explanation for hearing loss in SMPX-mutated patients. Additionally, we observed a clear muscular phenotype consisting of the defective organization and functioning of muscle fibers, strongly suggesting a potential role for the protein in the development of muscle fibers. This piece of evidence highlights the need for more in-depth analyses in search for possible correlations between SMPX mutations and muscular disorders in humans, thus potentially turning this non-syndromic hearing loss-associated gene into the genetic cause of dysfunctions characterized by more than one symptom, making SMPX a novel syndromic gene.
Genes / Markers
Figures
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Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping