Mitochondria contain several large multisubunit enzyme complexes that are composed of proteins encoded in the nuclear and mitochondrial genomes. Particularly for correct assembly of these enzyme complexes, expression of the respective mitochondrial and nuclear genes has to be coordinated to ensure correct stoichiometries of the protein subunits. Part of this control and the response to specific...

Mitochondria are the structures that produce the bulk part of the cellular energy currency ATP, which drives numerous energy requiring processes in the cell. This process involves a series of large enzyme complexes--the respiratory chain--that couples the transfer of electrons to the creation of a concentration gradient of protons across the inner mitochondrial membrane, which drives ATP synthe...

Complex I is the point of entry in the mitochondrial electron transport chain for NADH reducing equivalents, and it behaves as a regulatable pacemaker of respiratory ATP production in human cells. Defects in complex I are associated with several human neurological disorders, including primary mitochondrial diseases, Parkinson disease (PD), and Down syndrome, and understanding the activity and r...

The effect of caloric restriction (CR) (40%) on the rates of mitochondrial H2O2 production and oxygen consumption and oxidative damage to nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) was studied for short-term (6-wk) and long-term (1-year) periods in the heart of young and old rats. Short-term CR did not change any of the parameters measured. However, long-term CR significantly decreased th...

OBJECTIVE The enzyme telomerase and its catalytic subunit the telomerase reverse transcriptase (TERT) are important for maintenance of telomere length in the nucleus. Recent studies provided evidence for a mitochondrial localization of TERT. Therefore, we investigated the exact localization of TERT within the mitochondria and its function. METHODS AND RESULTS Here, we demonstrate that TERT is...

Trimetazidine is an anti-ischemic drug whose cytoprotective mechanisms are not yet fully understood (but until now mainly related to the trimetazidine-induced "metabolic shift" from lipid beta-oxidation to glucose aerobic oxidation). We studied the effect of trimetazidine on the mitochondrial function of ischemic Wistar rat hearts perfused with glucose, using a model of ex-vivo perfusion (Lange...

Mitochondrial disorders have the highest incidence among congenital metabolic disorders characterized by biochemical respiratory chain complex deficiencies. It occurs at a rate of 1 in 5,000 births, and has phenotypic and genetic heterogeneity. Mutations in about 1,500 nuclear encoded mitochondrial proteins may cause mitochondrial dysfunction of energy production and mitochondrial disorders. Mo...

BACKGROUND Reactive oxygen species (ROS) mediate the effects of anesthetic precondition to protect against ischemia and reperfusion injury, but the mechanisms of ROS generation remain unclear. In this study, the authors investigated if mitochondria-targeted antioxidant (mitotempol) abolishes the cardioprotective effects of anesthetic preconditioning. Further, the authors investigated the mechan...

T he electrochemical gradient over the inner mitochon-drial membrane is the driving force for cellular ATP production. For this, electrons, which are derived from suc-cinate and NADH, are passed along the mitochondrial electron transfer chain, and the resulting energy is used to pump protons. The transport of the positively charged protons into the mitochondrial inner membrane space builds up a...