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Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells
Published on: March 9, 2012
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FRET binding antenna reports spatiotemporal dynamics of GDI-Cdc42 GTPase interactions
Louis Hodgson1,2, Désirée Spiering1, Mohsen Sabouri-Ghomi3
1Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine.
Nature Chemical Biology
|August 9, 2016
Summary
Guanine-nucleotide dissociation inhibitors (GDIs) regulate cell motility by controlling Rho GTPase activity. New biosensors reveal GDIs tightly coordinate Cdc42 GTPase release and activation, crucial for cell movement.
Area of Science:
- Cell biology
- Molecular signaling
- Biochemistry
Background:
- Guanine-nucleotide dissociation inhibitors (GDIs) negatively regulate Rho family GTPases.
- GDIs sequester GTPases away from cellular membranes, impacting their activity.
- Understanding GDI-GTPase interactions is key to deciphering cell motility regulation.
Purpose of the Study:
- To investigate how GDI-Cdc42 interaction regulates localized Cdc42 activation during cell motility.
- To develop and utilize novel biosensors for real-time monitoring of GDI-GTPase interactions.
Main Methods:
- Development of a GDI.Cdc42 Fluorescence Resonance Energy Transfer (FRET) biosensor (FLARE) to detect GDI-Cdc42 binding.
- Computational multiplexing and simultaneous imaging techniques.
- Spatiotemporal analysis of GDI-Cdc42 interaction and Cdc42 activation during cell protrusion and retraction.
Main Results:
- The GDI.Cdc42 FLARE biosensor selectively reports binding to endogenous GDIs.
- Spatiotemporal dynamics revealed tight coordination between GTPase release and activation within 10 seconds.
- GDI-Cdc42 interactions are critical for the precise spatiotemporal regulation of Cdc42 activity.
Conclusions:
- GDI-Cdc42 interactions play a dynamic and critical role in regulating localized Cdc42 activation.
- This regulation is essential for controlling cell motility processes like protrusion and retraction.
- GDIs are not just sequestration proteins but active participants in signaling dynamics.
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