运动纤毛在调节动物细胞运动及各种生理生化功能方面发挥重要作用。辐条是运动纤毛的主要成分，决定纤毛的摆动方式，其缺陷可导致纤毛摆动异常甚至完全停止。同时，辐条缺陷也是导致人类不动纤毛综合症（PCD）的重要原因。因此，对辐条结构及功能的研究对认识纤毛的运动机理及PCD疾病具有重要意义。目前对辐条的研究还有很多不足，表现在：1）对辐条蛋白组成的认识主要基于10年前衣藻质谱鉴定的结果，随着冷冻电镜及超高分辨显微镜技术的发展，发现存在很多未知的辐条蛋白；2）近来发现，衣藻辐条结构不同于人类，缺少RS3完整结构，因此对RS3的研究需要借助于新的模式生物；3）部分辐条蛋白存在于纤毛之外，对其具体功能不甚清楚。基于此，本立项拟采用多种分子生物学手段，分离鉴定新型辐条蛋白，利用多种模式生物，研究辐条蛋白的功能，从进化的角度认识辐条的结构特征，同时也为人类PCD的研究提供帮助。

Motile cilia coordinate cell movement and play diverse biological functions. Radial spoke, the major structure component, determines the beating pattern of motile cilia. Abnormal ciliary motility due to radial spoke defects is one of the reasons of human primary ciliary dyskinesia (PCD). The structure and function of radial spoke proteins remain to be elucidated: First, most radial spoke proteins were identified over ten years ago through mass spectrometric analysis from the flagella of Chlamydomonas reinhardtii, while recent experiments with cryoelectron microscopy and super resolution microscopy suggest that many radial spoke proteins remain to be identified; Second, the third radial spoke structure (RS3) is absent in the flagella of Chlamydomonas, making this model inappropriate for the study of human RS3; Thirdly, some radial spoke proteins exist outside the cilia, whose function is still unknown. In this proposal, we aim to decipher the structure and function of radial spoke proteins using different model animals. By identifying novel components of radial spoke, it will not only help us understand the evolution of radial spoke, but also benefit the treatment of human PCD.