Christine Beeton, Ph.D.
Ph.D., Faculte des Sciences de Luminy, Marseille, France.
Postdoctoral, University of California, Irvine.
Our research focuses on potassium channels as therapeutic targets for chronic diseases. We are mainly interested in chronic inflammatory diseases, such as multiple sclerosis, rheumatoid arthritis, or asthma but have also begun working on myotonic dystrophy type 1.
Multiple sclerosis is a chronic inflammatory disease of the central nervous system. It is characterized by the desctruction of myelin and by glial scaring that forms areas of demyelination within the brain and spinal cord. These lesions alter nerve conduction and participate to the disabling neurological deficits observed in multiple sclerosis. The cause of multiple sclerosis remains largely unknown but the presence of large immune infiltrates in the white matter of patients suggests an autoimmune component to the disease.
Rheumatoid arthritis is also a chronic inflammatory disease. Unlike multiple sclerosis, rheumatoid arthritis is a systemic disease that mainly affects freely-moveable joints. It also has significant co-morbidities in the respiratory and cardiovascular systems. This diseases affects as many as 1% of the North American population and can cause severe disability. In this disease too, the immune system is thought to play an important role together with resident joint cells.
Allergic asthma is a chronic inflammatory disease of the airways and the lung parenchyma associated with airway hyperresponsiveness and mucus hypersecretion. Its prevalence is estimated at 5% of the population, asthma is therefore one of the most common chronic diseases worldwide and the incidence and frequency of its complications is increasing.
Myotonic dystrophy type 1 is an autosomal dominant neuromuscular disease. Affecting 1 in 8,000 people worldwide, it is the most common adult-onset muscular dystrophy. It is caused by an expansion of nucleotide CTG repeats in the 3’ untranslated region of the DMPK protein kinase gene. The disease is characterized by muscle wasting and multi-system disorder. The most prevalent causes of mortality in myotonic dystrophy type 1 are due to respiratory failure and cardiovascular disease leading to progressive left ventricular dysfunction, ischaemic heart disease, pulmonary embolism, or unexpected sudden death in which cardiac arrhythmias are suspected.
Potassium channels are transmembrane proteins that open and close in response to stimuli such as changes in membrane voltage or binding of ligands, such as calcium. Potassium channels therefore play crucial roles in regulating the function of a large number of electrically excitable cells and non-excitable cells. At least 78 genes encode potassium channels but their diversity is even higher at the functional level since different subunits can assemble into functional heteromultimers. Homo- and heteromultimers of potassium channels have restricted tissue distribution. All those characteristics make potassium channels attractive targets for drug development. Our projects evolve around two families of potassium channels, the voltage gated Kv1.x channels and the voltage- and calcium-regulated KCa1.1 channels in both the immune system and target tissues.
Major equipment available in the lab
- Tissue culture: 2 BSL2 biosafety cabinets, 1 CO2 incubator, 1 inverted microscope, 2 cryotanks, 1 cell harvester, 1 refrigerated centrifuge, and 1 non-refrigerated centrifuge.
- Electrophysiology: 1 manual patch-clamp setup (with fluorescence Olympus IX71 microscope, Heka EPC10-USB amplifier, & Eppendorf micromanipulator), 1 automated Nanion Port-a-Patch automated patch-clamp setup (with Heka EPC10-USB amplifier), 1 osmometer, 1 Heka pipet puller, and 1 Narishige microforge.
- Biochemistry and molecular biology: 1 thermocycler, 1 microcentrifuge, 1 plate reader, 1 gel scanner, 1 photometer, and small equipment for DNA and protein gels.
- Histology: 1 Olympus BX81 microscope equipped with a digital color camera and 1 cytocentrifuge.
- Computers: 7 desktop PCs, including one in the PI’s office, 2 connected to the patch-clamp setups, and one shared for data analysis using specialized software.
- And of course we have all the usual small equipment (balances, pH meter, water bath, sonicator, fridges, freezers, and more…).
National Multiple Sclerosis Society
Arthritis National Research Foundation
American Heart Association
Mrs. Clifford Elder White Graham Endowed Research Fund
Department of Defense
Kineta One, Inc.