Display Settings:


Send to:

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 2009 Apr 3;284(14):9109-14. doi: 10.1074/jbc.M809101200. Epub 2009 Feb 4.

Complex I is rate-limiting for oxygen consumption in the nerve terminal.

Author information

  • 1School of Biochemistry and Immunology and Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.


Metabolic control analysis was used to determine the spread of control exerted by the electron transport chain complexes over oxygen consumption rates in the nerve terminal. Oxygen consumption rates and electron transport chain complex activities were titrated with appropriate inhibitors to determine the flux control coefficients and the inhibition thresholds in rat brain synaptosomes. The flux control coefficients for complex I, complex II/III, complex III, and complex IV were found to be 0.30 +/- 0.07, 0.20 +/- 0.03, 0.20 +/- 0.05, and 0.08 +/- 0.05, respectively. Inhibition thresholds for complex I, complex II/III, complex III, and complex IV activities were determined to be approximately 10, approximately 30, approximately 35, and 50-65%, respectively, before major changes in oxygen consumption rates were observed. These results indicate that, of the electron transport chain components, complex I exerts a high level of control over synaptosomal bioenergetics, suggesting that complex I deficiencies that are present in neurodegenerative disorders, such as Parkinson disease, are sufficient to compromise oxygen consumption in the synaptosomal model of the nerve terminal.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk