Related Experiment Video

Updated: Jul 18, 2026

Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells
10:27

Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells

Published on: March 9, 2012

Activated Cdc42/Rac reconstitutes Fcepsilon RI-mediated Ca2+ mobilization and degranulation in mutant RBL mast cells

E Hong-Geller1, D Holowka, R P Siraganian

  • 1Departments of Molecular Medicine, and Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA.

Proceedings of the National Academy of Sciences of the United States of America
|February 7, 2001
PubMed
Summary

Mast cells require calcium (Ca2+) mobilization for degranulation during allergic responses. This study reveals that Cdc42 and Rac1 GTPase activation are essential for antigen-stimulated Ca2+ signaling and mast cell degranulation.

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