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My ORCID is 0000-0002-4263-180X.
My Scopus ID is 7005381745.
My NIH COMMONS name is TDECOURSEY.
Research Areas:
The properties and biological functions of ion channels are long-term interests of Tom DeCoursey’s laboratory. A major focus in recent years is the voltage-gated proton channel (Hv1). Modulation of the voltage-dependence of this channel by pHo and pHi ensures that it opens only when the electrochemical gradient for H+ is outward (in most species). In other words, when the proton channel opens, it extrudes acid from cells. In a long collaboration with Dr. Vladimir V. Cherny and others, the behavior of proton channels has been explored in alveolar epithelial cells and in white blood cells (human neutrophils and eosinophils). Immune cells engulf (phagocytose) bacteria and kill parasites by secreting reactive oxygen species (e.g., Chlorox). The enzyme responsible for these heroic actions is NADPH oxidase. This enzyme moves electrons across the cell membrane to form superoxide anion near the invading critters. We measure the electron movement directly as an electrical current. For each electron that leaves, one proton stays in the cell. To prevent massive depolarization as well as acidification, protons exit the cell through proton channels. Without H+ efflux, the killing process would be interrupted prematurely. Fortunately, proton channels are activated, relieving the cell of excess acid, and preventing depolarization. The discovery of proton channels has been a great boon to cells, who until this time had to use other, less efficient means of extruding acid. Identification of proton channel genes in 2006 has transformed the field. More functions are described each year, and structure-function studies are appearing. The channel was shown to be a dimer, with conduction pathway in each protomer. The dimer gates cooperatively - both protomers need to move before either conducts. New genes (over a dozen at last count) are appearing at a high rate. The proton channel resists efforts to crystallize it. The first crystal structure was reported in 2014 by Takeshita et al, is likely closed, and is of a chimera with a Voltage-Sensing Phosphatase. Hv1 triggers the flash in bioluminescent dinoflagellates (Smith et al, 2011), which were recently active in Tasmania!
My Faculty Profile at Rush University Medical Center:
https://www.rushu.rush.edu/faculty/thomas-decoursey-phd
My Laboratory:
https://www.rushu.rush.edu/research/departmental-research/physiology-and-biophysics-research/laboratory-tom-decoursey-phd
http://www.phys.rush.edu/TomD/physiotd.html
My NCBI Bibliography:
https://www.ncbi.nlm.nih.gov/pubmed/?term=DeCoursey+TE
My Scopus:
https://www.scopus.com/authid/detail.uri?authorId=7005381745
My ORCID:
http://orcid.org/0000-0002-4263-180X
Education:
PhD, University of Cincinnati College of Medicine
BA, McPherson College, Kansas
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