mRNAs of enzymes involved in energy metabolism and mtDNA are increased in endurance-trained athletes
1995; American Physical Society; Volume: 269; Issue: 3 Linguagem: Inglês
10.1152/ajpcell.1995.269.3.c619
ISSN1522-1563
AutoresA. Puntschart, H. Claassen, K Jostarndt, Hans Hoppeler, R. Billeter,
Tópico(s)Adipose Tissue and Metabolism
ResumoImprovements in endurance capacity by training are associated with structural and biochemical adaptations of working muscles that affect the mitochondrial compartment. We investigated whether the 1.8-fold higher mitochondrial volume density in a group of endurance-trained athletes compared with untrained subjects was reflected by higher steady-state levels of mRNAs coding for components of the oxidative phosphorylation pathway using a quantitative polymerase chain reaction approach. We found that mitochondrially encoded RNAs (cytochrome-c oxidase subunit I, NADH reductase subunit 6, 16S rRNA), as well as nuclear-encoded RNAs (cytochrome-c oxidase subunit IV, succinate dehydrogenase, fumarase) are all increased coordinately in the athletes (1.54- to 1.94-fold). In addition, mitochondrial (mt) DNA concentration was also 1.55-fold higher in the trained athletes, whereas genomic DNA was not changed. Our findings thus show similar RNA expression of mitochondrially encoded genes in sedentary and endurance-trained subjects, whereas pretranslational control mechanisms account for higher levels of nuclear-encoded RNAs in the athletes.
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