Referenced in: none

Automatically associated channels: Kv10.1

Title: A photoactivable probe for calcium binding proteins.

Authors: Adrian Israelson, Laetitia Arzoine, Salah Abu-Hamad, Vladimir Khodorkovsky, Varda Shoshan-Barmatz

Journal, date & volume: Chem. Biol., 2005 Nov , 12, 1169-78

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/16298296

Abstract
Ca2+ as a signaling molecule carries information pivotal to cell life and death via its reversible interaction with a specific site in a protein. Although numerous Ca2+-dependent activities are known, the proteins responsible for some of these activities remain unidentified. We synthesized and characterized a photoreactive reagent, azido ruthenium (AzRu), which interacts specifically with Ca2+ binding proteins and strongly inhibits their Ca2+-dependent activities, regardless of their catalytic mechanisms or functional state as purified proteins, embedded in the membrane or in intact cells. As expected from a Ca2+ binding protein-specific reagent, AzRu had no effect on Ca2+-independent and Mg2+-dependent activities. Az103Ru covalently bound, and specifically labeled, known Ca2+ binding proteins. AzRu is a photoreactive reagent that provides an approach for identification of Ca2+ binding proteins, characterization of their binding sites, and exploration of new Ca2+-dependent processes.