Cilia formation is essential for human life. One of the earliest events in the ciliogenesis program is the recruitment of tau-tubulin kinase 2 (TTBK2) by the centriole distal appendage component CEP164. Due to the lack of high-resolution structural information on this complex, it is unclear how it is affected in human ciliopathies such as nephronophthisis. Furthermore, it is poorly understood if binding to CEP164 influences TTBK2 activities. Here, we present a detailed biochemical, structural, and functional analysis of the CEP164-TTBK2 complex and demonstrate how it is compromised by two ciliopathic mutations in CEP164. Moreover, we also provide insights into how binding to CEP164 is coordinated with TTBK2 activities. Together, our data deepen our understanding of a crucial step in cilia formation and will inform future studies aimed at restoring CEP164 functionality in a debilitating human ciliopathy.

纤毛的形成对于人类生命至关重要。纤毛发生过程中最早的事件之一是中心粒远端附属物成分 CEP164 募集 tau 微管蛋白激酶 2 (TTBK2)。由于缺乏该复合物的高分辨率结构信息，尚不清楚它如何在肾痨等人类纤毛病中受到影响。此外，人们对与 CEP164 的结合是否会影响 TTBK2 活性知之甚少。在这里，我们对 CEP164-TTBK2 复合物进行了详细的生化、结构和功能分析，并展示了 CEP164 中的两个纤毛病突变如何对其造成损害。此外，我们还深入了解了 CEP164 的结合如何与 TTBK2 活动相协调。总之，我们的数据加深了我们对纤毛形成关键步骤的理解，并将为未来旨在恢复 CEP164 在衰弱的人类纤毛病中的功能的研究提供信息。