Acid-sensing ion channel-1b in the stereocilia of mammalian cochlear hair cells.
We investigated whether amiloride-blockable proton-gated cation channels ASIC1a (acid-sensing ion channel-1a) and ASIC1b are expressed in the stereocilia of mouse cochlear hair cells. In-situ hybridization studies showed that ASIC1b transcripts, but not ASIC1a transcripts, were expressed in the inner and outer hair cells. Fluorescent immunohistochemical and immunogold electron microscopic analyses revealed that the ASIC1b channels were located at the insertions of the stereocilia into the hair cells. Our findings provide a novel molecular key to the understanding of cochlear physiology and pathophysiology.
Ugawa
Shinya
S
Department of Molecular Morphology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Aichi, Japan. ugawa@med.nagoya-cu.ac.jp
Inagaki
Akira
A
Yamamura
Hisao
H
Ueda
Takashi
T
Ishida
Yusuke
Y
Kajita
Kenji
K
Shimizu
Hideo
H
Shimada
Shoichi
S
D062565:Acid Sensing Ion Channels; D000818:Animals; D015153:Blotting, Western / Q000379:methods; D002923:Cilia / Q000378:metabolism / Q000648:ultrastructure; D003051:Cochlea / Q000166:cytology*; D006198:Hair Cells, Auditory / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D007150:Immunohistochemistry / Q000379:methods; D017403:In Situ Hybridization / Q000379:methods; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D016253:Microscopy, Immunoelectron / Q000379:methods; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D010590:Phalloidine; D015222:Sodium Channels / Q000235:genetics / Q000378:metabolism*
C568267:ASIC1 protein, mouse; D062565:Acid Sensing Ion Channels; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D015222:Sodium Channels; D010590:Phalloidine