Long Huan, Huang Kaiyao
Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.
Front Cell Dev Biol. 2020 Jan 13;7:381. doi: 10.3389/fcell.2019.00381. eCollection 2019.
Cilia and flagella are highly conserved organelles in eukaryotic cells that drive cell movement and act as cell antennae that receive and transmit signals. In addition to receiving and transducing external signals that activate signal cascades, cilia also secrete ciliary ectosomes that send signals to recipient cells, and thereby mediate cell-cell communication. Abnormal ciliary function leads to various ciliopathies, and the precise transport and localization of ciliary membrane proteins are essential for cilium function. This review summarizes current knowledge about the transport processes of ciliary membrane proteins after their synthesis at the endoplasmic reticulum: modification and sorting in the Golgi apparatus, transport through vesicles to the ciliary base, entrance into cilia through the diffusion barrier, and turnover by ectosome secretion. The molecular mechanisms and regulation involved in each step are also discussed. Transport of ciliary membrane proteins is a complex, precise cellular process coordinated among multiple organelles. By systematically analyzing the existing research, we identify topics that should be further investigated to promote progress in this field of research.
纤毛和鞭毛是真核细胞中高度保守的细胞器，它们驱动细胞运动，并作为接收和传递信号的细胞触角。除了接收和转导激活信号级联反应的外部信号外，纤毛还分泌纤毛外泌体，将信号发送到受体细胞，从而介导细胞间通讯。纤毛功能异常会导致各种纤毛病，而纤毛膜蛋白的精确运输和定位对于纤毛功能至关重要。本文综述了目前关于纤毛膜蛋白在内质网合成后运输过程的知识：在高尔基体中的修饰和分选、通过囊泡运输到纤毛基部、通过扩散屏障进入纤毛以及通过外泌体分泌进行周转。还讨论了每个步骤所涉及的分子机制和调控。纤毛膜蛋白的运输是一个复杂、精确的细胞过程，由多个细胞器协调完成。通过系统分析现有研究，我们确定了该研究领域中有待进一步研究以推动进展的课题。
