Calcium Green FlAsH as a genetically targeted small-molecule calcium indicator.

ABSTRACT: Intracellular Ca(2+) regulates numerous proteins and cellular functions and can vary substantially over submicron and submillisecond scales, so precisely localized fast detection is desirable. We have created a approximately 1-kDa biarsenical Ca(2+) indicator, called Calcium Green FlAsH (CaGF, 1), to probe [Ca(2+)] surrounding genetically targeted proteins. CaGF attached to a tetracysteine motif becomes ten-fold more fluorescent upon binding Ca(2+), with a K(d) of approximately 100 microM, <1-ms kinetics and good Mg(2+) rejection. In HeLa cells expressing tetracysteine-tagged connexin 43, CaGF labels gap junctions and reports Ca(2+) waves after injury. Total internal reflection microscopy of tetracysteine-tagged, CaGF-labeled alpha(1C) L-type calcium channels shows fast-rising depolarizati

SUBMITTER: Tour O 

PROVIDER: S-EPMC2909385 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature