Experimental investigation of mechano-electrical signal transduction in a simple auditory organ [in the hearing organ of bushcrickets]

我们理解听觉过程的关键是将声音信号转换为听觉感觉细胞中的受体电位，即机械电转导（MET）。到目前为止，这一过程仍然没有得到充分理解。在这种情况下，高频声音的灵敏度和尖锐的调谐感知特别感兴趣。蟋蟀的听觉器官，听觉嵴，在功能上类似于哺乳动物的基底膜。它的特点是音调排列的感觉细胞和非常好的高频听力。与哺乳动物的耳蜗相反，听嵴的直线形状允许沿着器官的整个长度进行体内实验，因此可以对它进行整个频率调谐。为了获得有关信号转导过程的信息，我们将测量声音诱导的单个感觉细胞复合体（耳蜗）的运动以及感觉细胞电位的变化。一旦我们研究了整个听觉器官中涉及信号转导和调谐的基本过程，我们将借助物理和化学操作来研究机械和电气组件对转导过程的影响。所收集的数据将提供关于细胞微力学对听嵴振动特性的潜在主动反馈的信息。利用听嵴作为一个简单的模型系统，我们将了解MET的基本过程，tonotop相互作用和听觉器官感觉细胞的机械反应。

Critical to our understanding of the hearing process is the conversion of a sound signal into a receptor potential in the auditory sensory cells, the mechano-electrical transduction (MET). To date this process is still not fully understood. In this context, the sensitivity and sharply-tuned perception of high-frequency sound is of particular interest. The hearing organ of bushcrickets, the crista acustica, is functionally similar to the basilar membrane of mammals. It is characterized by tonotopically arranged sensory cells and a very good high-frequency hearing. In contrast to the cochlea of mammals, the straight shape of the crista acustica allows in-vivo experiments along the whole length of the organ and thus the entire frequency tuning of it. To obtain information about the signal transduction process we will measure sound-induced motion of single sensory cell complexes (scolopidia) in addition to changes in the potential of the sensory cells. Once we have examined the fundamental processes involved in the signal transduction and tuning throughout the entire hearing organ, we will investigate the influence of the mechanical and electrical components on the transduction process with the aid of physical and chemical manipulations. The collected data will provide information about potential active feedback of cellular micromechanics on the vibration characteristics of the crista acustica. Using the crista acustica as a simple model system, we will understand the fundamental processes of MET, tonotop interactions and mechanical reaction of sensory cells in the hearing organ.