This is a competing renewal application. The overall thrust of the project is to develop novel fluorescent sensing and imaging technology for understanding the biology of zinc, with a view to developing novel and improved diagnostics and therapies for human diseases. Evidence of zinc's role(s) in stroke, Alzheimer's disease, epilepsy, long term memory, gastrointestinal infectious disease, and type 2 diabetes has recently emerged, but a much more detailed understanding of zinc's involvement will be necessary in all these cases. Previously, we had developed protein-based fluorescence indicators with outstanding sensitivity, selectivity, and tunable kinetics;using this basic approach we were able for the first time to measure (in a resting cell) free zinc in the cytoplasm, and by use of an expressible indicator, in the resting mitochondrion. For the next cycle we propose to develop a palette of new ratiometric, expressible zinc indicators that will provide rapid, sensitive, and reliable zinc quantitation in many applications. We also are proposing to develop an accurate measurement of the expression of our biosensors in situ by microscopy;this basic approach may be useful to quantify protein expression in general. We also are proposing to apply our new sensing technology to answer questions of central importance that so far have resisted other investigators: Is hypoxia alone or the acidosis it induces responsible for the release of toxic zinc levels in ischemia? In the hippocampal formation in the brain, how much zinc ion is released in response to electrical stimulus, and how much of the zinc is taken up by the post-synaptic dendritic spines? Answers to these questions will help elucidate zinc's role in stroke (and suggest means for treatment, which currently are marginal), and in learning and memory formation.

Public Health Relevance

The proposed work will be vital for understanding the role(s) of zinc in intractable diseases such as stroke, Alzheimer's disease, epilepsy, type 2 diabetes, and others. This novel technology will provide the basis for new diagnostics and treatments.

Agency
National Institute of Health (NIH)
Institute
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Type
Research Project (R01)
Project #
2R01EB003924-05
Application #
7584936
Study Section
Neural Oxidative Metabolism and Death Study Section (NOMD)
Program Officer
Zhang, Yantian
Project Start
2004-08-15
Project End
2011-06-30
Budget Start
2009-07-01
Budget End
2010-06-30
Support Year
5
Fiscal Year
2009
Total Cost
$387,548
Indirect Cost
Name
University of Maryland Baltimore
Department
Biochemistry
Type
Schools of Medicine
DUNS #
188435911
City
Baltimore
State
MD
Country
United States
Zip Code
21201
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