Thermal sensitivity of oxidative phosphorylation in rat heart mitochondria: Does pyruvate dehydrogenase dictate the response to temperature?

Hélène Lemieux; Jean-Claude Tardif; Pierre U Blier

doi:10.1016/j.jtherbio.2009.12.003

Thermal sensitivity of oxidative phosphorylation in rat heart mitochondria: Does pyruvate dehydrogenase dictate the response to temperature?

J Therm Biol. 2010 Feb;35(2):105-111. doi: 10.1016/j.jtherbio.2009.12.003. Epub 2009 Dec 21.

Authors

Hélène Lemieux¹, Jean-Claude Tardif², Pierre U Blier¹

Affiliations

¹ Laboratoire de Biologie Intégrative, Université du Québec, 300 allée des Ursulines, Rimouski, Quebec, Canada G5L 3A1.
² Montreal Heart Institute and Université de Montréal, 5000 Bélanger Street, Montreal, Quebec, Canada H1T 1C8.

PMID: 28799912
DOI: 10.1016/j.jtherbio.2009.12.003

Abstract

To identify the most temperature-sensitive steps in the energy production pathways, we measured the thermal sensitivity of mitochondrial oxidative phosphorylation (OXPHOS), as well as that of the individual steps in this process in rat heart mitochondria. OXPHOS measured in the presence of pyruvate+malate as substrates have an unusually high thermal sensitivity between 5 and 15°C. Furthermore, the thermal sensitivity of OXPHOS correlates with the thermal sensitivity of pyruvate dehydrogenase between 5 and 35°C. Pyruvate dehydrogenase is a potential control point for pyruvate-supported mitochondrial respiration below physiological temperature in rat heart.