Spatio-temporal Fluorescence Analysis at the Single Cell Level Reveals Zinc
Fluxes Controlling Oocyte Cell Cycle and Fertilization
Thomas V. O’Halloran, Ph.D.
The Chemistry of Life Processes Institute; Robert H. Lurie Comprehensive Cancer
Center; Departments of Chemistry and Molecular Biosciences Northwestern University,
Evanston Il 60208-3113
Recent studies have shown that dramatic time-dependent fluctuations in intracellular
transition metal concentrations control key steps in regulating development,
proliferation, differentiation and growth. Quantitative single cell X-ray fluorescence
microscopy (ACS Chem Biol, 2011,15;6(7):716) and tomography experiments
(Nature Chemistry, 2015 PMCID: PMC4315321) at the APS (Argonne National
Laboratory) reveal fluctuations in metal concentrations in single cells and in
subcellular compartments, opening discovery of new signaling roles for zinc fluxes.
Coupled with results from new fluorescent probe molecules deployed in live cell
confocal fluorescence experiments, we find that fluxes of billions of zinc atoms in the
time course of seconds to hours are used by the cell to control key physiological
decisions at the earliest stages of oocyte maturation and fertilization. In this sense
zinc joins calcium and phosphorous as conductors of information in biological
signaling networks.