Dr. Patrick Lajoie

Assistant Professor, Departments of Anatomy & Cell Biology

Ph.D. University of British Columbia
B.Sc. Université du Québec à Montréal

Office: Medical Sciences Building 438
519-661-2111 Ext 88220

Research Interests:

Our lab is studying the mechanisms regulating secretory protein homeostasis under both normal and pathological conditions. We focus on understanding how the quality control machinery of the endoplasmic reticulum (ER) promotes efficient protein folding under various conditions. Proper folding and quality control of secretory proteins are crucial to cell viability. Accumulation of misfolded proteins can lead to loss of protein function and cell death. Cells activate the unfolded protein response (UPR) to cope with misfolded protein accumulation in the ER, but excessive UPR can trigger apoptosis. UPR activation has been associated with various diseases such as diabetes, Huntington’s disease and cardiac dysfunction. We employ mammalian tissue culture models, yeast genetics, molecular biology, quantitative live cell imaging techniques and high-throughput RNA-SEQ to understand how cells detect, respond and cope with misfolded proteins.

Current research interests include:

-The role of the UPR in Huntington’s disease

-Interplay between UPR and ribosome biogenesis

-UPR in cardiac hypertrophy

-Fitness of the secretory pathway in yeast aging


Current Projects:

  1. Lajoie P., Moir RD., Willis IM., Snapp EL. 2012. Kar2p availability defines various forms of endoplasmic reticulum stress in living cells.  Mol. Biol. Cell. 23(5): 955-64

  2. Lajoie P., Snapp EL. 2011. Changes in BiP availability reveal hypersensitivity to acute ER stress in cells expressing mutant huntingtin. J. Cell Sci. 124:3332-3343.

  3. Lajoie P., Snapp EL. 2010. Formation and toxicity of polyglutamine oligomers in living cells. PLoS One. 5(12):e15245

  4. Benedix J, Lajoie P, Jaiswal H, Burgard C, Greiner M, Jung M, Zimmermann R, Rospert S, Snapp EL and Dudek J. 2010. BiP modulates the affinity of its co-chaperone ERj1 to ribosomes. J Biol. Chem. 285(47):36427-33

  5. Müller L, de Escauriaza MD, Lajoie P, Theis M, Jung M, Müller A, Burgard C, Greiner M, Snapp EL, Dudek J, Zimmermann R. 2010. Evolutionary gain of function for the ER membrane protein Sec62 from yeast to humans. Mol Biol Cell. (5):691-703.