Related Experiment Video
Updated: Feb 3, 2026

Self-Assembly of Microtubule Tactoids
Published on: June 23, 2022
Rsph9 is critical for ciliary radial spoke assembly and central pair microtubule stability
Lei Zhu1,2, Hao Liu1,2, Yawen Chen1,2
1State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Shanghai, China.
Background Information:
In the "9+2"-type motile cilia, radial spokes (RSs) protruded from the nine peripheral microtubule doublets surround and interact with the central pair (CP) apparatus to regulate ciliary beat. RSPH9 is the human homologue of the essential protozoan RS head protein Rsp9. Its mutations in human primary ciliary dyskinesia patients, however, cause CP loss in a small portion of airway cilia without affecting the ciliary localization of other head proteins.
Results:
We characterized mouse Rsph9 and investigated its function in ependymal motile cilia. Rsph9 was specifically expressed in mouse tissues containing motile cilia and upregulated during multiciliation. Its ciliary localization complied with its putative role as an RS subunit. Depletion of Rsph9 by RNAi in mouse ependymal cilia resulted in a near complete CP loss and altered the ciliary beat pattern from planar to rotational. Multiple RS proteins, including those in the head, were also markedly downregulated in the Rsph9-depleted cilia.
Conclusion:
Rsph9 is essential for both the RS head assembly and the CP maintenance in mammalian ependymal cilia.
Significance:
Our results help to understand the assembly and functions of mammalian RS and pathology of RS-related ciliopathy.
More Related Videos
12:20Preparation of Segmented Microtubules to Study Motions Driven by the Disassembling Microtubule Ends
Published on: March 15, 2014
07:21Quantitative Microtubule Fractionation Technique to Separate Stable Microtubules, Labile Microtubules, and Free Tubulin in Mouse Tissues
Published on: November 17, 2023
Related Concept Videos
Drugs that Stabilize Microtubules
Microtubules
Assembly of Complex Microtubule Structures
Nuclear Stability
To hold positively charged protons together...
VSEPR Theory and the Effect of Lone Pairs
Radial System Protection
In a radial system with a fault downstream of the third breaker, ideally, only the third breaker will open, isolating the fault and interrupting the load connected beyond it. The second breaker has a longer delay setting,...