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Subcellular analysis of pigeon hair cells implicates vesicular trafficking in cuticulosome formation and maintenance.

ABSTRACT: Hair cells are specialized sensors located in the inner ear that enable the transduction of sound, motion, and gravity into neuronal impulses. In birds some hair cells contain an iron-rich organelle, the cuticulosome, that has been implicated in the magnetic sense. Here, we exploit histological, transcriptomic, and tomographic methods to investigate the development of cuticulosomes, as well as the molecular and subcellular architecture of cuticulosome positive hair cells. We show that this organelle forms rapidly after hatching in a process that involves vesicle fusion and nucleation of ferritin nanoparticles. We further report that transcripts involved in endocytosis, extracellular exosomes, and metal ion binding are differentially expressed in cuticulosome positive hair cells. These data suggest that the cuticulosome and the associated molecular machinery regulate the concentration of iron within the labyrinth of the inner ear, which might indirectly tune a magnetic sensor that relies on electromagnetic induction.

SUBMITTER: Nimpf S

PROVIDER: S-EPMC5699870 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Subcellular analysis of pigeon hair cells implicates vesicular trafficking in cuticulosome formation and maintenance.

Nimpf Simon S Malkemper Erich Pascal EP Lauwers Mattias M Ushakova Lyubov L Nordmann Gregory G Wenninger-Weinzierl Andrea A Burkard Thomas R TR Jacob Sonja S Heuser Thomas T Resch Guenter P GP Keays David A DA

eLife 20171115

Hair cells are specialized sensors located in the inner ear that enable the transduction of sound, motion, and gravity into neuronal impulses. In birds some hair cells contain an iron-rich organelle, the cuticulosome, that has been implicated in the magnetic sense. Here, we exploit histological, transcriptomic, and tomographic methods to investigate the development of cuticulosomes, as well as the molecular and subcellular architecture of cuticulosome positive hair cells. We show that this organ ...[more]

PMID: 29140244

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Subcellular analysis of pigeon hair cells implicates vesicular trafficking in cuticulosome formation and maintenance.

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Subcellular analysis of pigeon hair cells implicates vesicular trafficking in cuticulosome formation and maintenance.

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