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Updated: Jun 6, 2026

Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells
Published on: March 9, 2012
A photocleavable rapamycin conjugate for spatiotemporal control of small GTPase activity
Nobuhiro Umeda1, Tasuku Ueno, Christopher Pohlmeyer
1Department of Cell Biology, Center for Cell Dynamics, Johns Hopkins University, Baltimore, Maryland 21205, USA.
Abstract:
We developed a novel method to spatiotemporally control the activity of signaling molecules. A newly synthesized photocaged rapamycin derivative induced rapid dimerization of FKBP (FK-506 binding protein) and FRB (FKBP-rapamycin binding protein) upon UV irradiation. With this system and the spatially confined UV irradiation, we achieved subcellularly localized activation of Rac, a member of small GTPases. Our technique offers a powerful approach to studies of dynamic intracellular signaling events.
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