MagFRET: the first genetically encoded fluorescent Mg2+ sensor.

ABSTRACT: Magnesium has important structural, catalytic and signaling roles in cells, yet few tools exist to image this metal ion in real time and at subcellular resolution. Here we report the first genetically encoded sensor for Mg(2+), MagFRET-1. This sensor is based on the high-affinity Mg(2+) binding domain of human centrin 3 (HsCen3), which undergoes a transition from a molten-globular apo form to a compactly-folded Mg(2+)-bound state. Fusion of Cerulean and Citrine fluorescent domains to the ends of HsCen3, yielded MagFRET-1, which combines a physiologically relevant Mg(2+) affinity (K d = 148 µM) with a 50% increase in emission ratio upon Mg(2+) binding due to a change in FRET efficiency between Cerulean and Citrine. Mutations in the metal binding sites yielded MagFRET variants whose Mg(2+) a

SUBMITTER: Lindenburg LH 

PROVIDER: S-EPMC3846734 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature