1. Ciliary transition zone proteins coordinate ciliary protein composition and ectosome shedding
- Author
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Liang Wang, Xin Wen, Zhengmao Wang, Zaisheng Lin, Chunhong Li, Huilin Zhou, Huimin Yu, Yuhan Li, Yifei Cheng, Yuling Chen, Geer Lou, Junmin Pan, and Muqing Cao
- Subjects
Proteomics ,Multidisciplinary ,General Physics and Astronomy ,Membrane Proteins ,Cell Cycle Proteins ,General Chemistry ,Kidney Diseases, Cystic ,General Biochemistry, Genetics and Molecular Biology ,Cytoskeletal Proteins ,Antigens, Neoplasm ,Cell-Derived Microparticles ,Humans ,Cilia ,Chlamydomonas reinhardtii - Abstract
The transition zone (TZ) of the cilium/flagellum serves as a diffusion barrier that controls the entry/exit of ciliary proteins. Mutations of the TZ proteins disrupt barrier function and lead to multiple human diseases. However, the systematic regulation of ciliary composition and signaling-related processes by different TZ proteins is not completely understood. Here, we reveal that loss of TCTN1 in Chlamydomonas reinhardtii disrupts the assembly of wedge-shaped structures in the TZ. Proteomic analysis of cilia from WT and three TZ mutants, tctn1, cep290, and nphp4, shows a unique role of each TZ subunit in the regulation of ciliary composition, explaining the phenotypic diversity of different TZ mutants. Interestingly, we find that defects in the TZ impair the formation and biological activity of ciliary ectosomes. Collectively, our findings provide systematic insights into the regulation of ciliary composition by TZ proteins and reveal a link between the TZ and ciliary ectosomes.
- Published
- 2021