Skip to main content
  • Poster presentation
  • Open access
  • Published:

CSPP-L and EB3 localize to centriolar satellites and are required for satellite-dependent recruitment of ciliopathy proteins to the centrosome

Objective

Centrosome/Spindle Pole associated Protein 1 (CSPP1, JBTS21) mutations cause Joubert syndrome (JBTS) and JBTS-related ciliopathies. The large protein isoform CSPP-L is a ciliary protein required for ciliogenesis and stabilization of the ciliopathy protein RPGRIP1L (NPHP8/JBTS7/MKS5/FTM) at the ciliary transition zone (TZ). However, RPGRIP1L is dispensable for ciliogenesis and the mechanism by which CSPP-L promotes ciliogenesis is unclear.

Methods

We applied immunogold electron, immunofluorescence and fluorescence live cell microscopy to determine localization of CSPP-L at high spatial and temporal resolution. We elucidated the functional interplay of CSPP-L with centriolar satellites in hTERT-RPE1 and HeLa cells using biochemical analysis of CSPP-L complexes, siRNA modulated gene expression and quantitative immunofluoresecence microscopy.

Results

We show that CSPP-L localizes to centriolar satellites, in addition to axonemal microtubule (MT) plus ends and the TZ, and that the MT plus end-tracking protein EB3 also localizes to satellites. CSPP-L complexed with the known satellite component PCM1 and GFP-CSPP-L showed satellite-like dynamics. Importantly, CSPP-L depletion decreased formation of PCM1, CEP290 and EB3-comprising satellites, whereas depletion or inactivation of EB3 impaired centrosomal localization of CSPP-L.

Conclusion

Our results identify a new link between MT plus ends and centriolar satellites, and suggest that CSPP-L contributes to ciliogenesis by promoting EB3- and dynein-dependent recruitment of satellite components to the centrosome.

Author information

Authors and Affiliations

Authors

Rights and permissions

Open Access  This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.

The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.

To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/.

The Creative Commons Public Domain Dedication waiver (https://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Sternemalm, J., Geimer, S., Aarnes, E. et al. CSPP-L and EB3 localize to centriolar satellites and are required for satellite-dependent recruitment of ciliopathy proteins to the centrosome. Cilia 4 (Suppl 1), P76 (2015). https://doi.org/10.1186/2046-2530-4-S1-P76

Download citation

  • Published:

  • DOI: https://doi.org/10.1186/2046-2530-4-S1-P76

Keywords