John Heikkila carries out research in molecular and cell biology and is a world expert on amphibian heat shock protein gene expression and function. Physiology, Cell and Developmental Biology Molecular Genetics Journal Editorship Cell Stress and Chaperones, Editorial Board Member Biochemistry and Cell Biology, Editorial Board Member 1980 PhD Department of Zoology, University of Toronto 1976 MSc Department of Zoology, University of Toronto 1973 BSc Life Sciences, University of Toronto

All organisms undergo a heat shock or stress response when exposed to temperatures a few degrees above their normal or to certain environmental stressors – including some heavy metals or oxidizing agents – or pathophysiological conditions such as loss of blood flow, fever, tissue injury and disease states. During the stress response, cells manufacture heat shock proteins (HSPs) – a class of molecular chaperone – that help repair the damage and provide tolerance against further stresses. HSPs are synthesized to maintain the solubility of partially unfolded protein, prevent their aggregation into toxic forms and assist in their refolding. Dr. Heikkila is actively researching HSP gene expression using the frog model system, Xenopus laevis. Analysis of the molecular response of a model amphibian tissue culture cell system to environmental stress. Isolation and cloning of heat shock or stress protein genes and analysis of their regulation and molecular chaperone function.

Heikkila, J.J. (2017) The expression and function of hsp30-like small heat shock protein genes in amphibians, birds, fish, and reptiles. Comp. Biochem. Physiol. Part A. 203, 179-192. Shirriff, C.S., Heikkila, J.J. (2017) Characterization of cadmium chloride-induced BiP accumulation in Xenopus laevis A6 kidney epithelial cells. Comp. Biochem. Physiol. Part C. 191, 117-128. Khamis, I., Chan, D.W., Shirriff, C.S., Campbell, J.H., Heikkila, J.J. 2016. Expression and localization of the Xenopus laevis small heat shock protein, HSPB6 (HSP20), in A6 kidney epithelial cells. Comp. Biochem. Physiol. A. Molec. Integr. Physiol. 201: 12-21. Khan, S., Khamis, I., Heikkila, J.J. 2015. The small heat shock protein, HSP30, is associated with aggresome-like inclusion bodies in proteasomal inhibitor-, arsenite-, and cadmium-treated Xenopus kidney cells. Comp. Biochem. Physiol. A. Molecular and Integrative Physiology. 189: 130-140. Music, E., Khan, S., Khamis, I., Heikkila, J.J. 2014. Accumulation of heme oxygenase-1 (HSP32) in Xenopus laevis A6 kidney epithelial cells treated with sodium arsenite, cadmium chloride or proteasomal inhibitors. Comp. Biochem. Physiology C. Toxicol. Pharmacol. 166: 75-87. Khan, S., Heikkila, J.J. 2014. Distinct patterns of HSP30 and HSP70 degradation in Xenopus laevis A6 cells recovering from thermal stress. Comp. Biochem. Physiol. A. Molec. Integr. Biol. 168,1-10. Khamis, I., Heikkila, J.J. 2013. Enhanced HSP30 and HSP70 accumulation in Xenopus cells subjected to concurrent sodium arsenite and cadmium chloride stress. Comp. Biochem. Physiology C. Toxicol. Pharmacol. 158: 165-172. Khan, S., Rammeloo, A.W., Heikkila, J.J. 2012. Withaferin A induces proteasome inhibition, endoplasmic reticulum stress, the heat shock response and acquisition of thermotolerance. PloS One 7: e50547. Brunt, J.J., Khan, S., Heikkila, J.J. 2012. Sodium arsenite and cadmium chloride induction of proteasomal inhibition and HSP accumulation in Xenopus laevis A6 kidney epithelial cells. Comp. Biochem. Physiology C. Toxicol. Pharmacol. 155: 307-317.