与普雷斯结合不会影响小鼠外毛细胞的非常高频复杂非线性电容 (cNLC)
bioRxiv : the preprint server for biology
|February 14, 2024
概括
普雷斯蒂安·普雷斯蒂安 (Prestin Prestin) 是一个
科学领域:
- 听觉神经科学 听觉神经科学
- 分子生物物理学的分子生物物理学.
背景情况:
- 前列素 (SLC26a5) 对于哺乳动物的耳放大至关重要,增强听觉灵敏度和频率选择性.
- 它的功能依赖于电压依赖的电荷运动,称为非线性电容 (NLC).
- 离子以前被认为可以调节前的动力学,特别是在较低的频率.
研究的目的:
- 为了研究NLC在老鼠外毛细胞 (OHC) 的频率响应,一种具有超声波听觉的物种.
- 为了确定化物结合在高频预功能中的作用.
- 为了探索控制普雷斯在高频率下类似压电的行为因素.
主要方法:
- 在小鼠OHC中研究了NLC频率响应.
- 利用分子动力学 (MD) 模拟来评估前突变体中的阴离子结合.
- 在S396E试验小鼠中检查了NLC频率切断值 (F is).
- 在野生类型 (WT) 和突变预备中评估NLC的应力灵敏度.
主要成果:
- 鼠标NLC的特征频率截止值 (F is) 约为27kHz.
- 在结口袋中的单点突变 (S396E,S398E) 消除了离子敏感性和结合.
- 在S396E敲入小鼠中的NLC Fis保持不变,表明化物不是高频活动的关键.
- 在S396E突变体中,NLC的张力灵敏度与WT相似,这表明化物没有在电性行为中参与.
结论:
- 在小鼠中,高频 prestin 功能很可能是由膜内的粘弹性负荷控制的,而不是化物相互作用.
- 对耳放大器的特定物种的听觉要求可能涉及对前列蛋白的外部机械负荷的修改,而不是其蛋白质-离子相互作用.
- 普雷斯的核心结构和离子结合口袋在各种物种中都保持不变,这意味着外部机械因素推动了听觉频率范围的进化适应.
相关概念视频
Hair Cells
40.4K
Hair cells are the sensory receptors of the auditory system—they transduce mechanical sound waves into electrical energy that the nervous system can understand. Hair cells are located in the organ of Corti within the cochlea of the inner ear, between the basilar and tectorial membranes. The actual sensory receptors are called inner hair cells. The outer hair cells serve other functions, such as sound amplification in the cochlea, and are not discussed in detail here.
40.4K
The Cochlea
44.9K
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
44.9K
Patch Clamp
5.5K
Many fundamental cell functions such as muscle contraction and nerve transmission rely on the electrical signals produced by the movement of positively and negatively charged ions across the cell membrane. One competent method to record current flowing across the whole cell or single ion channel is the patch-clamp technique.
In this method, a glass micropipette containing electrolyte solution is tightly sealed against a small portion of the cell membrane. As a result, a patch of the cell...
In this method, a glass micropipette containing electrolyte solution is tightly sealed against a small portion of the cell membrane. As a result, a patch of the cell...
5.5K


