The small GTPase RSG1 controls a final step in primary cilia initiation

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Updated: Jun 26, 2026

RhoC GTPase Activation Assay
09:58

RhoC GTPase Activation Assay

Published on: August 22, 2010

Stephanie O Agbu1,2, Yinwen Liang1, Aimin Liu3

  • 1Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY.

The Journal of Cell Biology
|October 18, 2017
PubMed

Insights

The small GTPase RSG1 is crucial for primary cilia formation during embryonic development. Loss of RSG1 impairs cilia initiation and leads to developmental defects by affecting mother centriole maturation.

Area of Science:

  • Cell Biology
  • Developmental Biology
  • Molecular Biology

Background:

  • Primary cilia are vital for development and tissue homeostasis.
  • Centriole remodeling mechanisms for cilia initiation are not fully understood.

Purpose of the Study:

  • Investigate the role of the small GTPase RSG1 in primary cilia formation.
  • Elucidate the mechanisms by which RSG1 influences centriole maturation and cilia initiation.

Main Methods:

  • Analysis of mouse embryos lacking RSG1 (Rsg1 mutant).
  • Assessment of primary cilia number, length, and Hedgehog pathway protein trafficking.
  • Localization studies of RSG1 and associated proteins at the mother centriole.

Main Results:

  • Rsg1 mutant embryos exhibit developmental abnormalities and die by embryonic day 12.5.
  • Fewer primary cilia form in Rsg1 mutants, with normal length and protein trafficking.
  • RSG1 is essential for mother centriole recruitment of cilia initiation proteins and docking with ciliary vesicles, but not for axonemal microtubule elongation.

Conclusions:

  • RSG1 plays a critical role in the final maturation of the mother centriole and ciliary vesicles.
  • This maturation step is necessary for the proper extension of the ciliary axoneme.
  • RSG1 is a key regulator of cilia-dependent signaling pathways essential for embryonic development.

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