Visualizing ascorbate-triggered release of labile copper within living cells using a ratiometric fluorescent sensor.
We present the synthesis, properties, and biological applications of Ratio-Coppersensor-1 (RCS1), a new water-soluble fluorescent sensor for ratiometric imaging of copper in living cells. RCS1 combines an asymmetric BODIPY reporter and thioether-based ligand receptor to provide high selectivity and sensitivity for Cu(+) over other biologically relevant metal ions, including Cu(2+) and Zn(2+), a ca. 20-fold fluorescence ratio change upon Cu(+) binding, and visible excitation and emission profiles compatible with standard fluorescence microscopy filter sets. Live-cell confocal microscopy experiments show that RCS1 is membrane-permeable and can sense changes in the levels of labile Cu(+) pools within living cells by ratiometric imaging, including expansion of endogenous stores of exchangeable intracellular Cu(+) triggered by ascorbate stimulation in kidney and brain cells.
Domaille
Dylan W
DW
Department of Chemistry and the Howard Hughes Medical Institute, University of California, Berkeley, California 94720, USA.
Zeng
Li
L
Chang
Christopher J
CJ
D000818:Animals; D001205:Ascorbic Acid / Q000737:chemistry*; D001921:Brain / Q000166:cytology; D045744:Cell Line, Tumor; D003300:Copper / Q000032:analysis*; D005456:Fluorescent Dyes / Q000138:chemical synthesis*; D007668:Kidney / Q000166:cytology; D018613:Microscopy, Confocal / Q000379:methods*; D015394:Molecular Structure; D051381:Rats
D005456:Fluorescent Dyes; D003300:Copper; D001205:Ascorbic Acid