The hot mitochondrion paradox: reconciling theory and experiment

Experiments by Chretien and coworkers suggest that mitochondria are 10 degrees C hotter than their surroundings. Steady-state theoretical estimates place this difference at a maximum of 10(-5)degrees C. This millionfold disagreement may be called the 'hot mitochondrion paradox'. It is suggested that every proton translocated via ATP synthase sparks a picosecond temperature-difference spike of the order of magnitude measured by Chretien et al. Time averaging of these spikes recovers the theoretical value. Further, a temporal and spatial superposition of the fluorescence intensity of a very large number of molecular thermometer molecules in the sample can give the appearance of a steady signal. The inner mitochondria) membrane appears to be flanked by temperature differences fluctuating in time and along the membrane's surface, with 'hot' and 'cold' spots as ultrashort temperature spikes.

Automated summary

This article discusses the "hot mitochondrion paradox," which refers to the contradiction between two different observations regarding the temperature difference in mitochondria. Experimental results show that mitochondria are 10 degrees C hotter than their surroundings, while theoretical estimates suggest a maximum difference of 10(-5) degrees C. The article suggests that proton translocation via ATP synthase may cause picosecond temperature-difference spikes, explaining the disagreement between the observations.