Limna - Lausanne Integrative Metabolism Nutrition Alliance

SEMINAR

Monday 8th October 2018
14h00 - EPFL, SV Building, Room SV 1717

Cellomics of mitochondrial morphofunction


Dr. Werner Koopman

Radboud Centre of Mitochondrial Medicine, Nijmegen, The Netherlands

Host: Christopher Wall (NIHS)

Abstract

Mitochondria play a central role in cellular (patho)physiology and display a highly variable morphology that is probably coupled to their functional state. Our research aims to quantitatively understand the molecular connection between mitochondrial metabolism and (ultra)structure with particular attention to redox and energy homeostasis. In primary fibroblasts from Leigh Syndrome (LS) patients, isolated CI deficiency is associated with mitochondrial morphological and functional changes and increased reactive oxygen species (ROS) levels. We developed a high-content (“cellomics”) strategy allowing unbiased and automated quantification of mitochondrial “morphofunction” (i.e. morphology and membrane potential), cellular parameters (size, confluence) and nuclear parameters (number, morphology) in intact living Primary Human Skin Fibroblasts. Cells are cultured in 96-well plates and stained with tetramethyl rhodamine methyl ester (TMRM), Calcein-AM and Hoechst 33258. Next, multispectral fluorescence images are acquired using automated microscopy and processed to extract 44 descriptors. Subsequently, the descriptor data is subjected to a quality control (QC) algorithm based upon Principal Component Analysis (PCA) and interpreted using univariate, bivariate and multivariate analysis. Using a machine learning strategy, we discriminated between fibroblasts of a healthy individual and an LS patient based upon their mitochondrial morpho-functional phenotype. This allowed evaluating the therapeutic potential of newly developed small-molecules.

Selected publications:

- Teixeira, J., Basit, F., Swarts, H.G., Forkink, M., Oliveira, P.J., Willems, P.H.G.M., Koopman, W.J.H. (2018) Extracellular acidification induces ROS- and mPTP mediated death in HEK293 cells. Redox Biol. 15:394-404.
- Basit, F., van Oppen, L.M.P.E., Schöckel, L., Bossenbroek, H.M., van Emst-de Vries, S.E., Hermeling, J.C.W., Grefte, S., Kopitz, C., Heroult, M., Willems, P.H.G.M., Koopman, W.J.H. (2017) Mitochondrial complex I inhibition triggers a mitophagy-dependent ROS increase leading to necroptosis and ferroptosis in melanoma cells. Cell Death Dis. 8:e2716
- Iannetti, E.F., Smeitink, J.A.M., Beyrath, J., Willems, P.H.G.M., Koopman, W.J.H. (2016) Multiplexed high-content analysis of mitochondrial morphofunction using live-cell microscopy. Nature Protoc. 11:1693-1710.
- Liemburg-Apers, D.C., Wagenaars, J.A.L., Willems, P.H.G.M., Koopman, W.J.H. (2016) Acute inhibition of mitochondrial complex I and III triggers LKB1-, AMPK-, and SIRT2-dependent stimulation of GLUT1 activity. J. Cell Sci. 129:4411-4423.
- Koopman, W.J.H., Beyrath, J., Fung, W., Koene, S., Rodenburg, R.R., Willems, P.H.G.M., Smeitink, J.A.M. (2016) Mitochondrial disorders in children: toward development of small-molecule treatment strategies. EMBO Mol. Med. 8:311-27.
- Blanchet, L., Smeitink, J.A.M., Breuer, M.E., van Emst-de Vries, S.E., Vogels, C., Pellegrini, M., Jonckheere, A.I., Rodenburg, R.J.T., Buydens, L.M.C., Beyrath, J., Willems, P.H.G.M., Koopman, W.J.H. (2015) Analysis of small molecule phenotypic effects using combined mitochondrial morpho-functional fingerprinting and machine learning. Sci. Rep. 5:8035.
- Willems, P.H.G.M., Rossignol, R., Dieteren, C.E.J., Murphy, M.P., Koopman, W.J.H. (2015) Redox homeostasis and mitochondrial dynamics. Cell Metab. 22:207-18.
- Koopman, W.J.H., Distelmaier, F., Smeitink, J.A.M., Willems, P.H.G.M. (2013) OXPHOS mutations and neurodegeneration. EMBO J. 32:9-29.
- Koopman, W.J.H., Willems, P.H.G.M., Smeitink, J.A.M. (2012) Monogenic mitochondrial disorders. N. Eng. J. Med. 366:1132-1141.
- Dieteren, C.E.J., Gielen, S.C.A.M., Nijtmans, L.G.J., Smeitink, J.A.M., Swarts H.G., Brock, R., Willems, P.H.G.M., Koopman, W.J.H. (2011) Solute diffusion is hindered in the mitochondrial matrix. Proc. Natl. Acad. Sci. USA 108:8657-8662.