Copper is an essential trace element, which is critical to human health. It serves as a cofactor for many fundamental biological reactions, and is required in processes such as respiration, superoxide disproportionation, degradation of amines, or for iron mobilization and uptake. Because free copper ions catalyze the production of highly reactive hydroxyl radicals, which can damage lipids, proteins, DNA, and other biomolecules, copper uptake, distribution, and incorporation into proteins require a sophisticated machinery. Because the extracellular availability of copper may vary over time, cells are required to maintain buffer sites not only as a defense against deficiency, but also as protection from abnormally high levels. While great progress has been made in understanding the mechanisms of copper uptake, distribution, and regulation on a molecular level, still little is known about the subcellular location of such temporal storage sites and their redistribution during normal cell function or in specific disease states. To study these fundamental processes, new techniques are required for visualizing the dynamics of cellular copper in context of a live cell and to identify associated organelles or compartments. The goal of this grant application is to develop tools that will enable biologists to visualize cellular copper by combining two powerful imaging modalities, light and X-ray fluorescence microscopy. The former approach entails the development of membrane diffusible high-contrast- ratio copper-responsive fluorescent probes that will be suitable for interrogating the subcellular location and dynamics of kinetically labile copper pools in live cells. The second imaging modality is a highly sensitive synchrotron-based microanalytical technique that will provide quantitative information about the distribution of total copper and other transition elements in fixed cells. In order to bridge the two complementary techniques, we will develop a catalytically amplifiable xenobiotic fluorescent labeling approach, thus enabling direct correlative light and X-ray fluorescence microscopy of copper and associated cellular structures. Both imaging techniques will be applied to elucidate the role of the Golgi apparatus in copper redistribution and inheritance during mitosis and cell proliferation. The developed tools are expected to be of critical importance for elucidating other aspects of copper homeostasis and for the long-term development of novel diagnostic and therapeutic tools that will aid in combating copper related human diseases.

Public Health Relevance

Copper is an essential trace element, which is critical to human health. An increasing number of diseases, including Wilson disease, Menkes syndrome, or Alzheimer's disease, are caused by impaired copper transport and regulation. We propose the development of sensitive probes and techniques that will be suitable to visualize copper by light and X-ray fluorescence microscopy, as these tools are expected to significantly aid and advance studies of copper storage and regulation, thus help unravel the fundamental mechanisms of these diseases.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Research Project (R01)
Project #
Application #
Study Section
Macromolecular Structure and Function A Study Section (MSFA)
Program Officer
Anderson, Vernon
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Georgia Institute of Technology
Schools of Arts and Sciences
United States
Zip Code
Friscourt, Frédéric; Fahrni, Christoph J; Boons, Geert-Jan (2015) Fluorogenic Strain-Promoted Alkyne-Diazo Cycloadditions. Chemistry 21:13996-4001
Morgan, M Thomas; Sumalekshmy, S; Sarwar, Mysha et al. (2014) Probing ternary complex equilibria of crown ether ligands by time-resolved fluorescence spectroscopy. J Phys Chem B 118:14196-202
Fahrni, Christoph J (2013) Synthetic fluorescent probes for monovalent copper. Curr Opin Chem Biol 17:656-62
Morgan, M Thomas; Bagchi, Pritha; Fahrni, Christoph J (2013) High-contrast fluorescence sensing of aqueous Cu(I) with triarylpyrazoline probes: dissecting the roles of ligand donor strength and excited state proton transfer. Dalton Trans 42:3240-8
Bagchi, Pritha; Morgan, M Thomas; Bacsa, John et al. (2013) Robust affinity standards for Cu(I) biochemistry. J Am Chem Soc 135:18549-59
McRae, Reagan; Lai, Barry; Fahrni, Christoph J (2013) Subcellular redistribution and mitotic inheritance of transition metals in proliferating mouse fibroblast cells. Metallomics 5:52-61
Nekongo, Emmanuel E; Bagchi, Pritha; Fahrni, Christoph J et al. (2012) 9-Aryl-9-xanthenols: a convenient platform for the design of fluorimetric and colorimetric pH indicators. Org Biomol Chem 10:9214-8
Friscourt, Frederic; Fahrni, Christoph J; Boons, Geert-Jan (2012) A fluorogenic probe for the catalyst-free detection of azide-tagged molecules. J Am Chem Soc 134:18809-15
Chaudhry, Aneese F; Mandal, Subrata; Hardcastle, Kenneth I et al. (2011) High-contrast Cu(I)-selective fluorescent probes based on synergistic electronic and conformational switching. Chem Sci 2:1016-1024
Morgan, M Thomas; Bagchi, Pritha; Fahrni, Christoph J (2011) Designed to dissolve: suppression of colloidal aggregation of Cu(I)-selective fluorescent probes in aqueous buffer and in-gel detection of a metallochaperone. J Am Chem Soc 133:15906-9

Showing the most recent 10 out of 19 publications