[Frontiers in Bioscience, Landmark, 20, 229-246, January 1, 2015]

Morphological control of mitochondrial bioenergetics

Tianzheng Yu 1 , Li Wang 1 , Yisang Yoon 1

1Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912


1. Abstract
2. Introduction
3. Molecular mechanisms of mitochondrial fission and fusion
    3.1. Mitochondrial fission
      3.1.1. Mitochondrial fission by DLP1 and its receptors
      3.1.2. Regulation of mitochondrial fission through DLP1 phosphorylation
    3.2. Mitochondrial fusion
      3.2.1. Mitochondrial fusion by Mfn and OPA1
      3.2.2. More on Mfn and OPA1
4. Mitochondrial bioenergetics and morphology
    4.1. Mitochondrial bioenergetics – a simplistic view
    4.2. Mitochondrial morphology and energetic states: bi-directional influence
    4.3. Mitochondrial morphology and functionality in physio-pathological settings
    4.4. Control of respiration coupling: a mechanism linking mitochondrial morphology and bioenergetic activity?
5. Conclusion
6. Acknowlegements
7. References


The major function of mitochondria is production and supply of cellular energy. Mitochondria are highly dynamic organelles undergoing frequent shape changes via fission and fusion. Many studies have elucidated the molecular components mediating fission and fusion and their regulatory mechanisms, and mitochondrial shape change is now recognized as an essential cellular process that is closely associated with functional states of mitochondria. This review updates the recent advancements in fission and fusion mechanisms, and discusses the bi-directional relationship between mitochondrial morphology and energetic states in physio-pathological settings.


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Key Words: Mitochondria, Fission, Fusion, Morphology, Dynamics, DLP1, Drp1, Mfn, OPA1, Bioenergetics, Review

Send correspondence to: Yisang Yoon, Department of Physiology, Medical College of Georgia, Georgia Regents University, 1120 15th Street, Augusta, GA 30912, Tel: 706-721-7859, Fax: 706-721- 7299, E-mail: yyoon@gru.edu