The mitochondrial small heat-shock protein protects NADH:ubiquinone oxidoreductase of the electron transport chain during heat stress in plants.
Functional inactivation of the mitochondrial small heat-shock protein (lmw Hsp) in submitochondrial vesicles using protein-specific antibodies indicated that this protein protects NADH:ubiquinone oxidoreductase (complex I), and consequently electron transport from complex I to cytochrome c:O2 oxidoreductase (complex IV). Lmw Hsp function completely accounted for heat acclimation of complex I electron transport in pre-heat-stressed plants. Addition of purified lmw Hsp to submitochondrial vesicles lacking this Hsp increased complex I electron transport rates 100% in submitochondrial vesicles assayed at high temperatures. These results indicate that production of the mitochondrial lmw Hsp is an important adaptation to heat stress in plants.
Downs
C A
CA
Department of Biology, University of Charleston, SC 29424, USA. cadowns@technologist.com
Heckathorn
S A
SA
D004579:Electron Transport / Q000502:physiology; D005638:Fruit / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000302:isolation & purification / Q000494:pharmacology / Q000502:physiology*; D006358:Hot Temperature; D008928:Mitochondria / Q000378:metabolism; D009097:Multienzyme Complexes / Q000378:metabolism; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000378:metabolism*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D010085:Oxidative Phosphorylation; D010940:Plant Proteins / Q000302:isolation & purification / Q000494:pharmacology / Q000502:physiology*
D006360:Heat-Shock Proteins; C110899:LMW heat shock protein, Fragaria x ananassa; D009097:Multienzyme Complexes; D010940:Plant Proteins; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D016660:NAD(P)H Dehydrogenase (Quinone)