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Updated: Apr 27, 2026

Pull-down of Calmodulin-binding Proteins
Published on: January 23, 2012
Collecting data to determine the Ca²⁺-binding properties of DM-nitrophen and proteins
1Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, California 90095;
Abstract:
Conventional techniques used to measure Ca(2+) binding are too slow to determine accurately the fast binding kinetics of most molecules such as Ca(2+)-binding proteins (CBPs). We have developed an ultra-fast in vitro technique for measuring the Ca(2+)-binding properties of CBPs following flash photolysis of caged Ca(2+). Although the details of the setup, the mathematics, and the analysis involved in this technique have been published elsewhere, many of the practical details regarding the actual measurements have, until now, only been described minimally. Here, we present a protocol to gather the data necessary to determine the kinetic properties of a caged-Ca(2+) compound and a CBP.
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