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Updated: Jun 23, 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
SPIN90-IRSp53 complex participates in Rac-induced membrane ruffling
Carmen Teodorof1, Jeom Il Bae, Seon-Myung Kim
1Bio Imaging Research Center, Cell Dynamics Research Center, Department of Life Science, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, South Korea.
Experimental Cell Research
|May 23, 2009
Summary
SPIN90 and IRSp53 form a complex that regulates actin organization and cell motility. This interaction is crucial for forming membrane protrusions like lamellipodia and ruffles, essential for cell movement.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- SPIN90 is recognized as a critical regulator of the actin cytoskeleton.
- Understanding protein interactions is key to elucidating cellular processes.
Purpose of the Study:
- To investigate the interaction between SPIN90 and IRSp53.
- To determine the role of this complex in actin cytoskeletal organization and cell motility.
Main Methods:
- Utilized the BioGRID database to identify potential binding partners.
- Confirmed in vivo complex formation using co-expression in COS-7 cells.
- Investigated the effects of SPIN90 knockdown via siRNA and competitive inhibition assays.
Main Results:
- Identified IRSp53 as a binding partner of SPIN90, forming a complex via the SPIN90 proline-rich domain (PRD) and IRSp53 SH3 domain.
- SPIN90 and IRSp53 cooperate in Rac activation and form complexes at the cell's leading edge.
- PDGF treatment induced colocalization of SPIN90 and IRSp53 at membrane protrusions; SPIN90 knockdown reduced these protrusions and IRSp53 localization.
- Inhibition of SPIN90-IRSp53 binding reduced ruffle formation.
Conclusions:
- SPIN90 and IRSp53 form a functional complex that plays a significant role in regulating actin dynamics.
- This SPIN90-IRSp53 interaction is essential for the formation of membrane protrusions, including lamellipodia and ruffles, which are critical for cell motility.
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