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Updated: Jul 14, 2026

Detection of Small GTPase Prenylation and GTP Binding Using Membrane Fractionation and GTPase-linked Immunosorbent Assay
Published on: November 11, 2018
GTPases in semaphorin signaling
1Abteilung Molekularbiologie, Institut für Allgemeine Zoologie und Genetik, Westfälische Wilhelms-Universität, Schlogplatz 5, 48149 Münster, Germany. apuschel@uni-muenster.de
Semaphorin receptors utilize GTPases for signaling. Plexins, key components, interact with GTPases and act as GTPase activating proteins (GAPs), regulating cellular responses.
Area of Science:
- Cell Biology
- Molecular Signaling
- Neuroscience
Background:
- Semaphorin receptors, crucial for cell communication, interact with GTPases.
- Plexins are integral membrane proteins and the signal-transducing part of semaphorin receptors.
- Plexins possess GTPase activating protein (GAP) activity, a unique function among membrane proteins.
Purpose of the Study:
- To review the role of GTPases in the signaling pathways of Plexin-A1 and Plexin-B1.
- To elucidate the interaction between plexins and GTPases in semaphorin receptor function.
Main Methods:
- Review of existing literature on plexin and GTPase interactions.
- Focus on studies analyzing Plexin-A1 (Sema3A receptor) and Plexin-B1 (Sema4D receptor).
Main Results:
- GTPases regulate plexin activity via interactions with the cytoplasmic domain.
- Plexin-A1 and Plexin-B1 associate with GTPase Rnd1, facilitating R-Ras GAP activity.
- GTPases R-Ras and Rho are essential downstream effectors for semaphorin-mediated repulsion.
Conclusions:
- GTPases are central regulators of plexin function in semaphorin signaling.
- Understanding plexin-GTPase interactions is key to deciphering semaphorin-driven cellular processes.
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