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Updated: Jun 25, 2026
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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
v-Crk regulates membrane dynamics and Rac activation.
1Cell Dynamics Research Center and Bioimaging Research Center, Department of Life Science, Gwangju Institute of Science and Technology, Buk-gu, Gwangju, Korea.
Cell Adhesion & Migration
|March 6, 2009
Summary
The oncogene v-Crk promotes cell migration by activating Rac1 signaling, even without Crk-associated substrate (CAS). This study shows v-Crk enhances cell spreading and lamellipodium dynamics in CAS-deficient cells.
Area of Science:
- Cell Biology
- Molecular Biology
- Oncology
Background:
- Cell migration is crucial for development and disease, involving adhesion, protrusion, and contraction.
- Crk-associated substrate (CAS) is a major substrate for Crk, influencing cell motility.
- v-Crk, an oncogene product, affects membrane ruffles and Rac1 activation.
Purpose of the Study:
- To investigate the role of v-Crk in cell migration, particularly its interaction with Rac1 in the absence of CAS.
- To determine if v-Crk can restore cell migration defects in CAS-deficient cells.
Main Methods:
- Utilized CAS-deficient mouse embryo fibroblasts (MEFs).
- Expressed v-Crk in CAS-deficient MEFs.
- Analyzed cell spreading, lamellipodium dynamics, and Rac1 activation/localization.
Main Results:
- CAS-deficient MEFs exhibited delayed cell spreading and reduced Rac1 activation/membrane targeting.
- v-Crk expression rescued these defects, increasing cell spreading and lamellipodium protrusion/retraction.
- v-Crk induced Rac1 activation and membrane targeting in CAS-deficient cells.
Conclusions:
- v-Crk signaling, through Rac1 activation, directly regulates membrane dynamics and cell migration.
- v-Crk acts as an effector molecule for Rac1 activation, promoting cell motility.
- v-Crk can overcome CAS deficiency to enhance cell migration.
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