1
|
Ogunbona OB, Claypool SM. Emerging Roles in the Biogenesis of Cytochrome c Oxidase for Members of the Mitochondrial Carrier Family. Front Cell Dev Biol 2019; 7:3. [PMID: 30766870 PMCID: PMC6365663 DOI: 10.3389/fcell.2019.00003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 01/10/2019] [Indexed: 12/11/2022] Open
Abstract
The mitochondrial carrier family (MCF) is a group of transport proteins that are mostly localized to the inner mitochondrial membrane where they facilitate the movement of various solutes across the membrane. Although these carriers represent potential targets for therapeutic application and are repeatedly associated with human disease, research on the MCF has not progressed commensurate to their physiologic and pathophysiologic importance. Many of the 53 MCF members in humans are orphans and lack known transport substrates. Even for the relatively well-studied members of this family, such as the ADP/ATP carrier and the uncoupling protein, there exist fundamental gaps in our understanding of their biological roles including a clear rationale for the existence of multiple isoforms. Here, we briefly review this important family of mitochondrial carriers, provide a few salient examples of their diverse metabolic roles and disease associations, and then focus on an emerging link between several distinct MCF members, including the ADP/ATP carrier, and cytochrome c oxidase biogenesis. As the ADP/ATP carrier is regarded as the paradigm of the entire MCF, its newly established role in regulating translation of the mitochondrial genome highlights that we still have a lot to learn about these metabolite transporters.
Collapse
Affiliation(s)
- Oluwaseun B. Ogunbona
- Department of Physiology, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
- Department of Pathology & Laboratory Medicine, School of Medicine, Emory University, Atlanta, GA, United States
| | - Steven M. Claypool
- Department of Physiology, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| |
Collapse
|
2
|
Molecular identification and functional characterisation of uncoupling protein 4 in larva and pupa fat body mitochondria from the beetle Zophobas atratus. Comp Biochem Physiol B Biochem Mol Biol 2012; 162:126-33. [DOI: 10.1016/j.cbpb.2012.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 03/26/2012] [Accepted: 03/27/2012] [Indexed: 01/20/2023]
|
3
|
Ramsden DB, Ho PW, Ho JW, Liu H, So DH, Tse H, Chan K, Ho S. Human neuronal uncoupling proteins 4 and 5 (UCP4 and UCP5): structural properties, regulation, and physiological role in protection against oxidative stress and mitochondrial dysfunction. Brain Behav 2012; 2:468-78. [PMID: 22950050 PMCID: PMC3432969 DOI: 10.1002/brb3.55] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 03/07/2012] [Accepted: 03/09/2012] [Indexed: 01/07/2023] Open
Abstract
Uncoupling proteins (UCPs) belong to a large family of mitochondrial solute carriers 25 (SLC25s) localized at the inner mitochondrial membrane. UCPs transport protons directly from the intermembrane space to the matrix. Of five structural homologues (UCP1 to 5), UCP4 and 5 are principally expressed in the central nervous system (CNS). Neurons derived their energy in the form of ATP that is generated through oxidative phosphorylation carried out by five multiprotein complexes (Complexes I-V) embedded in the inner mitochondrial membrane. In oxidative phosphorylation, the flow of electrons generated by the oxidation of substrates through the electron transport chain to molecular oxygen at Complex IV leads to the transport of protons from the matrix to the intermembrane space by Complex I, III, and IV. This movement of protons to the intermembrane space generates a proton gradient (mitochondrial membrane potential; MMP) across the inner membrane. Complex V (ATP synthase) uses this MMP to drive the conversion of ADP to ATP. Some electrons escape to oxygen-forming harmful reactive oxygen species (ROS). Proton leakage back to the matrix which bypasses Complex V resulting in a major reduction in ROS formation while having a minimal effect on MMP and hence, ATP synthesis; a process termed "mild uncoupling." UCPs act to promote this proton leakage as means to prevent excessive build up of MMP and ROS formation. In this review, we discuss the structure and function of mitochondrial UCPs 4 and 5 and factors influencing their expression. Hypotheses concerning the evolution of the two proteins are examined. The protective mechanisms of the two proteins against neurotoxins and their possible role in regulating intracellular calcium movement, particularly with regard to the pathogenesis of Parkinson's disease are discussed.
Collapse
Affiliation(s)
- David B. Ramsden
- School of Medicine and School of Biosciences, University of Birmingham, United Kingdom
| | - Philip W.‐L. Ho
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong, PR China
- Research Centre of Heart, Brain, Hormone and Healthy Aging (HBHA), University of Hong Kong, Hong Kong, PR China
| | - Jessica W.‐M. Ho
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong, PR China
| | - Hui‐Fang Liu
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong, PR China
| | - Danny H.‐F. So
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong, PR China
| | - Ho‐Man Tse
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong, PR China
| | - Koon‐Ho Chan
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong, PR China
- Research Centre of Heart, Brain, Hormone and Healthy Aging (HBHA), University of Hong Kong, Hong Kong, PR China
| | - Shu‐Leong Ho
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong, PR China
- Research Centre of Heart, Brain, Hormone and Healthy Aging (HBHA), University of Hong Kong, Hong Kong, PR China
| |
Collapse
|