Expression of ASIC2 in ciliated cells and stereociliated cells.
Acid-sensing ion channel 2 (ASIC2) plays a role as a mechanorecptor and acid receptor in the peripheral and central nervous systems. However, several recent studies have suggested that ASIC2 is expressed in several organs, in addition to the nervous system. We have examined the expression and distribution of ASIC2 in rat ciliated cells (trachea and oviduct) and stereociliated cells (epididymis, Corti organ, and ampullary crest) by immunohistochemistry and transmission electron microscopy (TEM). Immunohistochemistry revealed that ASIC2 was expressed in both ciliated cells and stereociliated cells, but the localization differed between these cell types. In ciliated cells, ASIC2 was coexpressed with a cilial marker (acetylated tubulin). In stereociliated cells stained with a stereocilial marker (phalloidin), ASIC2 was observed in the cell body. Observation by TEM suggested that ASIC2 expression was present at the apical side of the cilial membrane in ciliated cells and at the apical side of the cell body in stereociliated cells. This study thus indicates that the proton receptor ASIC2 is expressed in both ciliated and stereociliated cells.
Department of Anatomy 1, Sapporo Medical University, School of Medicine, West 17 South 1, Chuo-ku, Sapporo, Hokkaido, Japan. ksin@sapmed.ac.jp
Shin
S
Kikuchi
Takafumi
T
Ninomiya
Tomoyuki
T
Kawamata
Haruyuki
H
Tatsumi
D062565:Acid Sensing Ion Channels; D000595:Amino Acid Sequence; D000818:Animals; D002923:Cilia / Q000378:metabolism* / Q000648:ultrastructure; D062626:Degenerin Sodium Channels; D004822:Epididymis / Q000166:cytology; D053503:Epithelial Sodium Channels / Q000235:genetics / Q000378:metabolism*; D005260:Female; D054777:Hair Cells, Ampulla / Q000166:cytology / Q000502:physiology*; D006198:Hair Cells, Auditory / Q000166:cytology / Q000502:physiology*; D008297:Male; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D010057:Oviducts / Q000166:cytology; D051381:Rats; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014132:Trachea / Q000166:cytology
D062565:Acid Sensing Ion Channels; C568425:Asic2 protein, rat; D062626:Degenerin Sodium Channels; D053503:Epithelial Sodium Channels; D009419:Nerve Tissue Proteins