TY - CHAP M1 - Book, Section TI - Mitochondrial DNA and Heritable Traits and Diseases A1 - L. Skorecki, Karl A1 - Cohen, Bruce H. A2 - Jameson, J. Larry A2 - Fauci, Anthony S. A2 - Kasper, Dennis L. A2 - Hauser, Stephen L. A2 - Longo, Dan L. A2 - Loscalzo, Joseph Y1 - 2018 N1 - T2 - Harrison's Principles of Internal Medicine, 20e AB - Mitochondria are cytoplasmic organelles whose major function is to generate ATP by the process of oxidative phosphorylation under aerobic conditions. This process is mediated by the respiratory electron transport chain (ETC) multiprotein enzyme complexes I–V and the two electron carriers, coenzyme Q10 (CoQ10) and cytochrome c. Other cellular processes to which mitochondria make a major contribution include apoptosis (programmed cell death) and additional cell type-specific functions (Table 472-1). The efficiency of the mitochondrial ETC in ATP production is a major determinant of overall body energy balance and thermogenesis. In addition, mitochondria are the predominant source of reactive oxygen species (ROS), whose rate of production also relates to the coupling of ATP production to oxygen consumption. Given the centrality of oxidative phosphorylation to the normal activities of almost all cells, it is not surprising that mitochondrial dysfunction can affect almost any organ system (Fig. 472-1). Until recently, it was thought that disruption of energy production was the source of the pathophysiology in those with mitochondrial dysfunction, but recent evidence suggests that free-radical production and the redox state of the mitochondria may play a role as well. Thus, physicians in many disciplines might encounter patients with mitochondrial diseases and should be aware of their existence and characteristics. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accesspharmacy.mhmedical.com/content.aspx?aid=1156521908 ER -