The epithelium has an apico-basal axis polarity that plays an important role in absorption, excretion and other physiological functions. In epithelial cells, a substantial number of non-centrosomal microtubules (MTs) are scattered in the cytoplasm with an apico-basal polarity and reorientate as epithelial cells perform different functions. Several previous studies have found that non-centrosomal MTs are nucleated at the centrosome, and then released and translocated elsewhere. However, the detailed process and molecular mechanism remain largely unknown. In this study, we found that Nezha, also called calmodulin-regulated spectrin-associated protein 3 (CAMSAP3), a non-centrosomal MT minus-end protein, accumulates in the pericentrosomal area and accompanies the release of MTs from the centrosome; whereas depletion of CAMSAP3 prevented MT release and instead caused focusing of MTs at centrosomes. Further studies demonstrated that CAMSAP3 precisely coordinates with dynein and katanin to regulate the MT detachment process. In conclusion, our results indicate that CAMSAP3 is a key molecule for generation of non-centrosomal MTs.
The authors declare no competing or financial interests.
Conceptualization: W.M.; Software: H.X.; Investigation: C.D., N.T., M.T.; Data curation: C.D., H.X., R.Z., N.T.; Writing - original draft: C.D.; Writing - review & editing: W.M.; Supervision: M.T.; Project administration: W.M.; Funding acquisition: W.M.
This work was supported by National Natural Science Foundation of China (31271426, 31571391), Ministry of Science and Technology of the People's Republic of China (2014CB942802) and the Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (25221104) to M.T.
Supplementary information available online at http://jcs.biologists.org/lookup/doi/10.1242/jcs.198010.supplemental
- Received September 27, 2016.
- Accepted March 17, 2017.
- © 2017. Published by The Company of Biologists Ltd