和整蛋白结合蛋白2 (CIB2) 控制耳外毛细胞中机械传感器通道的强力敏感性
bioRxiv : the preprint server for biology
|July 18, 2023
概括
和整合素结合蛋白2 (CIB2) 对于听力至关重要. 一种特定的CIB2突变会损害听觉毛细胞中的机电转导 (MET) 通道,影响声音感知,并可能导致聋.
科学领域:
- 听觉神经科学 听觉神经科学
- 分子生物学分子生物学
- 遗传学 遗传学是一种遗传学.
背景情况:
- 和整合素结合蛋白2 (CIB2) 对于听觉毛细胞功能至关重要.
- CIB2对于机电转导 (MET) 复合体至关重要,与TMC1/2通道相互作用.
- CIB2在MET通道封锁和力传输中的确切作用尚不清楚.
研究的目的:
- 调查与聋相关的CIB2突变 (p.R186W) 对MET通道属性的功能后果.
- 阐明CIB2在听觉毛细胞中的机械力转导中的作用.
主要方法:
- 在Cib2.2中生成了一个具有p.R186W突变的小鼠模型.
- 使用精确的机械刺激记录了耳外毛细胞中的MET电流.
- 使用AlphaFold2进行CIB2-TMC1/2相互作用的结构预测.
- 检查了立体尖结构和相关蛋白质.
主要成果:
- R186W突变导致可测量的MET电流,而不是完全的剥离.
- MET通道呈现出改变的门:休息开放概率增加,强力反应曲线更,适应性丧失.
- 突变减缓了MET通道激活,并破坏了立体尖结构,包括BAIAP2L2定位.
- AlphaFold2预测了CIB2-TMC1/2结合部位的破坏.
结论:
- CIB2 机械地限制TMC1/2通道,调节它们的力敏感度和动态范围.
- R186W突变损害了MET通道的力敏感性和力传递,可能导致听力损失.
- CIB2的作用超出了道运输范围,可以积极调节道力学.
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