毛细胞中单根静纤毛的钙成像：转导通道在纤毛顶部连接两端的定位。

Calcium imaging of single stereocilia in hair cells: localization of transduction channels at both ends of tip links.

作者信息

Denk W, Holt J R, Shepherd G M, Corey D P

机构信息

Biological Computation Research Department, AT&T Bell Laboratories, Murray Hill, New Jersey 07974, USA.

出版信息

Neuron. 1995 Dec;15(6):1311-21. doi: 10.1016/0896-6273(95)90010-1.

DOI:10.1016/0896-6273(95)90010-1

PMID:8845155

Abstract

Mechanically gated "transduction" channels in inner ear hair cells are thought to be connected to tip links stretched between adjacent stereocilia. To locate active channels, calcium-green fluorescence in single stereocilia was measured with two-photon laser scanning microscopy. Bundle deflection increased fluorescence in many but not all stereocilia; the increase was blocked by depolarization. The number of stereocilia responding was proportional to the transduction current, consistent with Ca2+ influx through transduction channels. Fluorescence rose first in the tips of stereocilia and then in the bases, in agreement with channel localization at the tips. Some of the shortest stereocilia in a bundle showed a fluorescence increase, as did some of the tallest, indicating that transduction channels can be at either or both ends of tip links.

摘要

内耳毛细胞中的机械门控“转导”通道被认为与相邻静纤毛之间伸展的纤毛顶部连接丝相连。为了定位活跃通道，使用双光子激光扫描显微镜测量单个静纤毛中的钙绿荧光。束状偏转增加了许多但并非所有静纤毛中的荧光；这种增加被去极化所阻断。有反应的静纤毛数量与转导电流成比例，这与通过转导通道的Ca2+内流一致。荧光首先在静纤毛的顶端升高，然后在基部升高，这与通道位于顶端的定位一致。一束中一些最短的静纤毛以及一些最长的静纤毛都显示出荧光增加，这表明转导通道可以位于纤毛顶部连接丝的一端或两端。