ZFIN ID: ZDB-PUB-041014-4
Mutated otopetrin 1 affects the genesis of otoliths and the localization of Starmaker in zebrafish
Söllner, C., Schwarz, H., Geisler, R., and Nicolson, T.
Date: 2004
Source: Development genes and evolution   214(12): 582-590 (Journal)
Registered Authors: Geisler, Robert, Nicolson, Teresa, Söllner, Christian
Keywords: Otolith biogenesis, Otopetrin 1, backstroke, Starmaker, Zebrafish
MeSH Terms:
  • Amino Acid Sequence
  • Animals
  • Cloning, Molecular
  • Ear, Inner/cytology
  • Epithelium/chemistry
  • Epithelium/metabolism
  • Gene Expression/drug effects
  • Membrane Proteins/genetics
  • Membrane Proteins/physiology*
  • Molecular Sequence Data
  • Mutation
  • Oligodeoxyribonucleotides, Antisense/genetics
  • Oligodeoxyribonucleotides, Antisense/pharmacology
  • Otolithic Membrane/embryology*
  • Otolithic Membrane/metabolism
  • Protein Transport/genetics
  • Protein Transport/physiology
  • RNA, Messenger/analysis
  • RNA, Messenger/metabolism
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish/physiology
  • Zebrafish Proteins/analysis*
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism
  • Zebrafish Proteins/physiology*
PubMed: 15480759 Full text @ Dev. Genes Evol.
Otoliths in bony fishes and otoconia in mammals are composite crystals consisting of calcium carbonate and proteins. These biominerals are part of the gravity and linear acceleration detection system of the inner ear. Mutations in otopetrin 1 have been shown to result in lack of otoconia in tilted and mergulhador mutant mice. The molecular function of Otopetrin 1, a novel protein that contains ten predicted transmembrane domains, however, has remained elusive. Here we show that a mutation in the orthologous gene in zebrafish is responsible for the complete absence of otoliths in backstroke mutants. We examined the localization of Starmaker, a secreted protein that is highly abundant in otoliths in backstroke mutants. Starmaker protein accumulated within cells of the otic epithelium, indicating a possible defect in secretion. Our data suggest that Otopetrin 1 in zebrafish may be involved in the protein trafficking of components required for formation of biominerals in the ear.