Professor of Medicine and Director of Proteomics at McGill University
«New Cell Biology through the study of Human Fatty Liver Disease»
Human pathophysiology presents unique opportunities to uncover new molecular mechanisms. Here, human liver tissue derived from donors and patients were subjected to subcellular fractionation to enrich for organelles including lipid droplets, mitochondria, endoplasmic reticulum and the Golgi apparatus. Each fraction was then analyzed by liquid chromatography tandem mass spectrometry and matched against the human-centric database NeXtProt. Spectral counting was used to compare fractions in a semi-quantitative manner and following hierarchal clustering, compiled using Java TreeView to yield heat map-based distributions of each protein and protein neighborhood. Lipid droplet proteins previously never assigned to this organelle were uncovered and are presently being elucidated functionally. Liver-derived fractions were also subjected to lipid analysis through shotgun mass spectrometry and using ion intensity, compiled as above enabling correlation between proteins and lipid profiles. The value of studying human samples in the context of disease to generate new cell biology will be demonstrated through findings made.