Deafness and cochlear fibrocyte alterations in mice deficient for the inner ear protein otospiralin.
In the cochlea, the mammalian auditory organ, fibrocytes of the mesenchymal nonsensory regions play important roles in cochlear physiology, including the maintenance of ionic and hydric components in the endolymph. Occurrence of human deafness in fibrocyte alterations underlines their critical roles in auditory function. We recently described a novel gene, Otos, which encodes otospiralin, a small protein of unknown function that is produced by the fibrocytes of the cochlea and vestibule. We now have generated mice with deletion of Otos and found that they show moderate deafness, with no frequency predominance. Histopathology revealed a degeneration of type II and IV fibrocytes, while hair cells and stria vascularis appeared normal. Together, these findings suggest that impairment of fibrocytes caused by the loss in otospiralin leads to abnormal cochlear physiology and auditory function. This moderate dysfunction may predispose to age-related hearing loss.
Delprat
Benjamin
B
INSERM U.583, Physiopathologie et Thérapie des Déficits Sensoriels et Moteurs, Institut des Neurosciences de Montpellier, Hôpital Saint-Eloi, BP 74103, 80, rue Augustin Fliche, 34295 Montpellier cedex 05, France. delprat@pasteur.fr
Ruel
Jérôme
J
Guitton
Matthieu J
MJ
Hamard
Ghyslaine
G
Lenoir
Marc
M
Pujol
Rémy
R
Puel
Jean-Luc
JL
Brabet
Philippe
P
Hamel
Christian P
CP
D000818:Animals; D001309:Auditory Threshold; D003051:Cochlea / Q000166:cytology* / Q000473:pathology / Q000502:physiology* / Q000503:physiopathology; D003638:Deafness / Q000235:genetics / Q000473:pathology / Q000503:physiopathology*; D004594:Electrophysiology; D018390:Gene Targeting; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D011506:Proteins / Q000235:genetics / Q000378:metabolism*
C503045:OTOS protein, human; C503046:Otos protein, mouse; D011506:Proteins