Ricci A J, Kachar B, Gale J, Van Netten S M
Neuroscience Center, Louisiana State University, New Orleans, LA 70112, USA.
J Membr Biol. 2006 Feb-Mar;209(2-3):71-88. doi: 10.1007/s00232-005-0834-8. Epub 2006 May 25.
The gating-spring theory of hair cell mechanotransduction channel activation was first postulated over twenty years ago. The basic tenets of this hypothesis have been reaffirmed in hair cells from both auditory and vestibular systems and across species. In fact, the basic findings have been reproduced in every hair cell type tested. A great deal of information regarding the structural, mechanical, molecular and biophysical properties of the sensory hair bundle and the mechanotransducer channel has accumulated over the past twenty years. The goal of this review is to investigate new data, using the gating spring hypothesis as the framework for discussion. Mechanisms of channel gating are presented in reference to the need for a molecular gating spring or for tethering to the intra- or extracellular compartments. Dynamics of the sensory hair bundle and the presence of motor proteins are discussed in reference to passive contributions of the hair bundle to gating compliance. And finally, the molecular identity of the channel is discussed in reference to known intrinsic properties of the native transducer channel.
毛细胞机械转导通道激活的门控弹簧理论早在二十多年前就首次被提出。这一假说的基本原理已在前庭和听觉系统的毛细胞以及不同物种中得到重申。事实上，在每一种测试过的毛细胞类型中都重现了这些基本发现。在过去二十年里，积累了大量关于感觉毛束和机械转导通道的结构、力学、分子及生物物理特性的信息。本综述的目的是以门控弹簧假说为讨论框架，研究新数据。根据分子门控弹簧或与细胞内或细胞外区室连接的需求，阐述通道门控机制。结合毛束对门控顺应性的被动作用，讨论感觉毛束的动力学和运动蛋白的存在。最后，根据天然转导通道已知的内在特性，讨论通道的分子身份。
