Is there a mitochondrial clock?

M. A. Aon; S. Cortassa; Brian O'Rourke

doi:10.1007/978-1-4020-8352-5_5

Is there a mitochondrial clock?

M. A. Aon, S. Cortassa, Brian O'Rourke

School of Medicine

Research output: Chapter in Book/Report/Conference proceeding › Chapter

Abstract

A mitochondrial oscillator dependent on reactive oxygen species (ROS) was first described in heart cells. Available evidence now indicates that mitochondrial energetic variables oscillate autonomously as part of a network of coupled oscillators under both physiological and pathological conditions. Moreover, emerging experimental and theoretical evidence indicates that mitochondrial network oscillations exhibit a wide range of frequencies, from milliseconds to hours, instead of a dominant frequency. With metabolic stress, the frequency spectrum narrows and a dominant oscillatory frequency appears, indicating the transition from physiological to pathophysiological behavior. Here we show that in the pathophysiological regime the mitochondrial oscillator of heart cells is temperature compensated within the range of 25-37°C with a Q₁₀ = 1.13. At temperatures higher than 37°C, the oscillations stop after a few cycles, whereas at temperatures lower than 25°C the oscillations are asynchronous. Using our mitochondrial oscillator model we show that this temperature compensation can be explained by kinetic compensation. Furthermore, we show that in the physiological domain temperature compensation acts to preserve the broad range of frequencies exhibited by the network of coupled mitochondrial oscillators. The results obtained indicate that the mitochondrial network behaves with the characteristics of a biological clock, giving rise to the intriguing hypothesis that it may function as an intracellular timekeeper across multiple time scales.

Original language	English (US)
Title of host publication	Ultradian Rhythms from Molecules to Mind: A New Vision of Life
Publisher	Springer Netherlands
Pages	129-144
Number of pages	16
ISBN (Print)	9781402083518
DOIs	https://doi.org/10.1007/978-1-4020-8352-5_5
State	Published - 2008

Fingerprint

Clocks

Temperature

Biological Clocks

Physiological Stress

Reactive Oxygen Species

Kinetics

Compensation and Redress

Keywords

biological clocks
fractal dynamics
membrane potential
Mitochondrial oscillations
power spectral and relative dispersional analyses
reactive oxygen species
temperature compensation

ASJC Scopus subject areas

Biochemistry, Genetics and Molecular Biology(all)

Cite this

Aon, M. A., Cortassa, S., & O'Rourke, B. (2008). Is there a mitochondrial clock? In Ultradian Rhythms from Molecules to Mind: A New Vision of Life (pp. 129-144). Springer Netherlands. https://doi.org/10.1007/978-1-4020-8352-5_5

Is there a mitochondrial clock? / Aon, M. A.; Cortassa, S.; O'Rourke, Brian.

Ultradian Rhythms from Molecules to Mind: A New Vision of Life. Springer Netherlands, 2008. p. 129-144.

Research output: Chapter in Book/Report/Conference proceeding › Chapter

Aon, MA, Cortassa, S & O'Rourke, B 2008, Is there a mitochondrial clock? in Ultradian Rhythms from Molecules to Mind: A New Vision of Life. Springer Netherlands, pp. 129-144. https://doi.org/10.1007/978-1-4020-8352-5_5

Aon MA, Cortassa S, O'Rourke B. Is there a mitochondrial clock? In Ultradian Rhythms from Molecules to Mind: A New Vision of Life. Springer Netherlands. 2008. p. 129-144 https://doi.org/10.1007/978-1-4020-8352-5_5

Aon, M. A. ; Cortassa, S. ; O'Rourke, Brian. / Is there a mitochondrial clock?. Ultradian Rhythms from Molecules to Mind: A New Vision of Life. Springer Netherlands, 2008. pp. 129-144

@inbook{b7bc11aa5cb746b191e95564ba81aa41,

title = "Is there a mitochondrial clock?",

abstract = "A mitochondrial oscillator dependent on reactive oxygen species (ROS) was first described in heart cells. Available evidence now indicates that mitochondrial energetic variables oscillate autonomously as part of a network of coupled oscillators under both physiological and pathological conditions. Moreover, emerging experimental and theoretical evidence indicates that mitochondrial network oscillations exhibit a wide range of frequencies, from milliseconds to hours, instead of a dominant frequency. With metabolic stress, the frequency spectrum narrows and a dominant oscillatory frequency appears, indicating the transition from physiological to pathophysiological behavior. Here we show that in the pathophysiological regime the mitochondrial oscillator of heart cells is temperature compensated within the range of 25-37°C with a Q10 = 1.13. At temperatures higher than 37°C, the oscillations stop after a few cycles, whereas at temperatures lower than 25°C the oscillations are asynchronous. Using our mitochondrial oscillator model we show that this temperature compensation can be explained by kinetic compensation. Furthermore, we show that in the physiological domain temperature compensation acts to preserve the broad range of frequencies exhibited by the network of coupled mitochondrial oscillators. The results obtained indicate that the mitochondrial network behaves with the characteristics of a biological clock, giving rise to the intriguing hypothesis that it may function as an intracellular timekeeper across multiple time scales.",

keywords = "biological clocks, fractal dynamics, membrane potential, Mitochondrial oscillations, power spectral and relative dispersional analyses, reactive oxygen species, temperature compensation",

author = "Aon, {M. A.} and S. Cortassa and Brian O'Rourke",

year = "2008",

doi = "10.1007/978-1-4020-8352-5_5",

language = "English (US)",

isbn = "9781402083518",

pages = "129--144",