Mitochondrial Adaptations to Variable Environments and Their Role in Animals' Stress Tolerance.

摘要: Mitochondria are the key organelles involved in energy and redox homeostasis, cellular signaling, survival. Animal mitochondria exquisitely sensitive to environmental stress, stress-induced changes mitochondrial integrity function have major consequences for organismal performance fitness. Studies model organisms such as terrestrial mammals insects showed that dysfunction is a cause of injury during pathological conditions insults hypoxia, ischemia-reperfusion, exposure toxins. However, animals from highly stressful environments (such intertidal zone ocean) can maintain despite intense rapid fluctuations abiotic associated intracellular milieu. Recent studies demonstrate (including mollusks, crustaceans, fish) capable maintaining activity electron transport system (ETS), ATP synthesis, coupling broad range temperature, osmolarity, ion content. mollusks also resistant hypoxia-reoxygenation show stability or even upregulation ETS synthesis capacity intermittent hypoxia. In contrast, pH optima respiration relatively narrow may reflect adaptation suppress metabolic rate shifts caused by extreme stress. Sensitivity anthropogenic pollutants trace metals) appears similar other mammals) lack these evolutionarily novel stressors. The mechanisms exceptional resilience salinity, hypoxic stress not yet fully understood organisms, recent they involve modulation (possibly due post-translation modification proteins), antioxidant defenses anticipation oxidative high proteases degradation damaged proteins. With rapidly developing molecular tools non-model future adaptations should pinpoint sites with passive tolerance and/or active regulation exposures investigate roles transduction signals, explore interplay between bioenergetics signaling facilitating survival environments.