Biochemistry and Biomedical Sciences
905-525-9140 ext. 22073
4H28 Health Sciences Centre
A.B. (Johns Hopkins University, Baltimore,
Ph.D. (Columbia University, NY)
Postdoctoral Fellow (Cornell University, NY)
Visiting Scientist, Yale University, CT
Visiting Scientist, Campomar Research Institute (Buenos Aires)
Avanti Award from the Biophysical Society for seminal studies in
Senior Investigator Award of the Canadian Institutes of Health Research
Fellow of the Biophysical Society
Fellow of the Spanish Biophysical Society
Fellow of the Biophysical Society of Canada
- Cell Biology and Regulation
Our laboratory is interested in the structure and properties of biological membranes. Many cell processes are intimately linked to membranes. These include most signal transduction phenomena, the entry of viruses into target cells, as well as the action of many drugs and cytotoxic agents. We are involved in several studies elucidating the molecular properties of membranes. These include the mechanism of viral fusion and the function of viral fusion proteins; the distribution of cholesterol in membranes and the role of proteins in sequestering cholesterol-rich domains; the role of lipids in signal transduction; the mechanism of action of antimicrobial peptides and the phenomenon of membrane lysis by different agents leading to cell death. In all of these areas, there is a focus in understanding the relationship between membrane molecular properties and the essential functions of the cell.
- Relationship between membrane properties and bilogical function
Many cell processes are intimately linked to their membranes. These include signal transduction phenomena, as well as the action of drugs and cytotoxic agents. We are studying the molecular properties of biological membranes and their biological function including the phosphatidylinositol cycle and the mechanisms by which the lipid intermediates of this cycle become enriched in specific acyl chains. The first step in this cycle is catalyzed by diacylglycerol kinase (DGK). In mammals there are 10 known isoforms of this enzyme, each having a different function and structure. Several disease processes have a connection with changes in expression of one or more of these isoforms each of which have specific roles in cells. We are also studying membrane curvature and the role of the acyl transferase enzyme, tafazzin, in determining the acyl chain composition of cardiolipin. Mutations in tafazzin lead to an inherited disease, Barth syndrome, in which patients suffer from altered cardiolipia and defective mitochondrial function. The roles of mitochondrial membrane curvature properties in processes connected to apoptosis is also under investigation.
1. Kagan, V.E., Jiang, J., Huang, Z., Tyurina, Y.Y., Desbourdes, C., Cottet-Rousselle, C., Dar, H.H., Verma, M., Tyurin, V.A., Kapralov, A.A., Cheikhi, A., Mao, G., Stolz, D., St. Croix, C.M., Watkins, S., Shen, Z., Li, Y., Greenberg, M.L., Tokarska-Schlattner, M., Boissan, M., Lacombe, M.-L., Epand, R.M., Chu, C.T., Mallampalli, R.K., Bayır H. and Schlattner U. (2016) NDPK-D (NM23-H4)-Mediated Externalization of Cardiolipin Enables Elimination of Depolarized Mitochondria by Mitophagy, Cell Death and Differentiation, 23, 1140-1151.
2. Kimura, T., Jennings, W., Epand, R.M. (2016) Roles of specific lipid species in the cell and their molecular mechanism, Prog Lipid Res., 62, 75-92.
3. Xu, Y., Phoon, C.K., Berno, B., D'Souza, K., Hoedt, E., Zhang, G., Neubert, T.A., Epand, R.M., Ren, M. and Schlame, M. (2016) Loss of protein association causes cardiolipin degradation in Barth syndrome, NatureChem Biology, 12 (2016) pp. 641-647.
4. So V., Jalan, D., Lemaire, M., Topham, M.K., Hatch, G.M. and Epand, R.M. (2016) Diacylglycerol kinase epsilon suppresses expression of p53 and glycerol kinase in mouse embryo fibroblasts, Biochimica Et Biophysica Acta - Molecular and Cell Biology of Lipids 1861, 1993-1999.
5. Epand R.M. and Chattopadhyay, A. (2016) Introduction to the Special Issue on the Properties and Functions of Cholesterol, Chem. Phys. Lipids 199, 1-2.
6. Epand, R.M., Bach, D. and Wachtel, E. (2016) In vitro determination of the solubility limit of cholesterol in phospholipid bilayers, Chem. Phys. Lipids 199, 3-10.
7. Epand, R.M., So, V., Jennings, W., Khadka, B., Gupta, R.S. and Lemaire, M., Diacylglycerol Kinase-ε: Properties and Biological Roles, Frontiers in Cell and Developmental Biology 4 (2016) p. 112.
8. Epand R.M. (2016) Features of the Phosphatidylinositol Cycle and its Role in Signal Transduction, J. Membr. Biol. 1-14.
9. Jennings,W., Doshi, S., Hota, P.K., Prodeus, A., Black, S. and Epand, R.M. (2017) Expression, Purification, and Properties of a Human Arachidonoyl-Specific Isoform of Diacylglycerol Kinase, Biochemistry 56, 1337-1347.