Related Experiment Video
Updated: Jun 26, 2026
09:58
RhoC GTPase Activation Assay
Published on: August 22, 2010
The small GTPase RSG1 controls a final step in primary cilia initiation
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
Summary
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.
More Related Videos
10:27Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells
Published on: March 9, 2012
13:51Detection of Small GTPase Prenylation and GTP Binding Using Membrane Fractionation and GTPase-linked Immunosorbent Assay
Published on: November 11, 2018
Related Concept Videos
02:14GTPases and their Regulation
Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins.
Large G-proteins, also known...
Large G-proteins, also known...
01:22Microtubules in Signaling
The primary cilium, made up of microtubules, acts as antennae on the cell surfaces for relaying external stimuli into the cells. These fine hair-like structures are present, generally one per cell. These are non-motile cilia in a 9+0 microtubules arrangement, where the central pair of microtubules are absent. The primary cilia arise from the basal body embedded in the cell membrane. Intraflagellar transport (IFT) carries requisite proteins from the cytoplasm to the cilium because the primary...
02:14GTPases and their Regulation
Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins.
Large G-proteins, also known...
Large G-proteins, also known...
01:25Rab Cascades
Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.
01:24Small GTPases - Ras and Rho
Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
Three regulatory proteins control their activity:
01:22Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...