title: Copper deficiency decreases complex IV but not complex I, II, III, or V in the mitochondrial respiratory chain in rat heart.
abstract: It has been documented that dietary copper (Cu) deficiency impairs mitochondrial respiratory function, which is catalyzed by 5 membrane-bound multiple protein complexes. However, there are few reports on the simultaneous analysis of Cu effect on the subunit protein expression on all 5 protein complexes. The present study was undertaken to determine the effect of Cu deficiency on each mitochondrial respiratory complex's protein expression in rat heart tissue with western-blot analysis. Male Sprague-Dawley rats were fed diets that were either Cu adequate (6.0 microg Cu/g diet, n = 5) or Cu deficient (0.3 microg Cu/g diet, n = 5) for 5 wk. The monoclonal antibody-based western-blot analysis suggested that the protein levels of 39-kDa and 30-kDa subunits in complex I; 70-kDa and 30-kDa subunits in complex II; core I and core II subunits in complex III; and alpha and beta subunits of F1 complex in complex V in both high-salt buffer (HSB) and low-salt buffer (LSB) protein fractions from heart tissue of Cu-deficient rats did not differ from those of Cu-adequate rats. However, the protein level of cytochrome c oxidase (CCO) subunit (COX) I, COX Vb, and COX VIb subunits in complex IV (CCO) in both HSB and LSB protein fractions from heart tissue of Cu-deficient rats was lower than those of Cu-adequate rats. Collectively, these data demonstrate that Cu deficiency decreases each tested subunit protein expression of complex IV but not those of complex I, II, III, and V in mitochondrial respiratory complexes.
authors.affiliation: USDA, Agricultural Research Service, Grand Forks Human Nutrition Research Center, Grand Forks, North Dakota 58202-9034, USA. hzeng@gfhnrc.ars.usda.gov
authors.forename: Huawei
authors.initials: H
authors.lastname: Zeng
authors.forename: Jack T
authors.initials: JT
authors.lastname: Saari
authors.forename: W Thomas
authors.initials: WT
authors.lastname: Johnson
mesh_terms: D000251:Adenosine Triphosphatases / Q000097:blood / Q000378:metabolism*; D000818:Animals; D002352:Carrier Proteins / Q000097:blood / Q000378:metabolism*; D003300:Copper / Q000172:deficiency* / Q000494:pharmacology*; D042967:Electron Transport Complex I / Q000378:metabolism*; D042963:Electron Transport Complex II / Q000378:metabolism*; D014450:Electron Transport Complex III / Q000187:drug effects / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000378:metabolism*; D008565:Membrane Proteins / Q000097:blood / Q000378:metabolism*; D008929:Mitochondria, Heart / Q000187:drug effects / Q000201:enzymology*; D025261:Mitochondrial Proton-Translocating ATPases; D023421:Models, Animal; D009097:Multienzyme Complexes / Q000187:drug effects / Q000378:metabolism*; D010101:Oxygen Consumption; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D002352:Carrier Proteins; D008565:Membrane Proteins; D009097:Multienzyme Complexes; D003300:Copper; D042963:Electron Transport Complex II; D003576:Electron Transport Complex IV; D000251:Adenosine Triphosphatases; D025261:Mitochondrial Proton-Translocating ATPases; D042967:Electron Transport Complex I; D014450:Electron Transport Complex III; C020439:oligomycin sensitivity-conferring protein