Cytochrome c oxidase-deficient patients have distinct subunit assembly profiles.
AuthorsHanson BJ, Carrozzo R, Piemonte F, Tessa A, Robinson BH, Capaldi RA
JournalJ Biol Chem
PubMed ID11278850
'Cytochrome c oxidase (COX) deficiency is the most common respiratory chain defect in childhood and is clinically heterogeneous. We report a study of six patients with COX deficiencies. Two of the patients had as yet undefined defects, three patients had Surf-1 mutations, and one patient had a 15-base pair deletion ... More
SM-20 is a novel mitochondrial protein that causes caspase-dependent cell death in nerve growth factor-dependent neurons.
AuthorsLipscomb EA, Sarmiere PD, Freeman RS
JournalJ Biol Chem
PubMed ID11060309
'Sympathetic neurons undergo protein synthesis-dependent apoptosis when deprived of nerve growth factor (NGF). Expression of SM-20 is up-regulated in NGF-deprived sympathetic neurons, and ectopic SM-20 is sufficient to promote neuronal death in the presence of NGF. We now report that SM-20 is a mitochondrial protein that promotes cell death through ... More
Mammalian cytochrome-c oxidase: characterization of enzyme and immunological detection of subunits in tissue extracts and whole cells.
AuthorsCapaldi RA, Marusich MF, Taanman JW
JournalMethods Enzymol
PubMed ID8592440
Complexity and tissue specificity of the mitochondrial respiratory chain.
AuthorsCapaldi RA, Halphen DG, Zhang YZ, Yanamura W
JournalJ Bioenerg Biomembr
PubMed ID2841307
There is a renewed interest in the structure and functioning of the mitochondrial respiratory chain with the realization that a number of genetic disorders result from defects in mitochondrial electron transfer. These socalled mitochondrial myopathies include diseases of muscle, heart, and brain. The respiratory chain can be fractionated into four ... More
Biochemical, genetic and immunoblot analyses of 17 patients with an isolated cytochrome c oxidase deficiency.
Authorsvon Kleist-Retzow JC, Vial E, Chantrel-Groussard K, Rötig A, Munnich A, Rustin P, Taanman JW
JournalBiochim Biophys Acta
PubMed ID10524227
Mitochondrial respiratory chain defects involving cytochrome c oxidase (COX) are found in a clinically heterogeneous group of diseases, yet the molecular basis of these disorders have been determined in only a limited number of cases. Here, we report the clinical, biochemical and molecular findings in 17 patients who all had ... More
Expression of mtDNA and nDNA encoded respiratory chain proteins in chemically and genetically-derived Rho0 human fibroblasts: a comparison of subunit proteins in normal fibroblasts treated with ethidium bromide and fibroblasts from a patient with mtDNA depletion syndrome.
AuthorsMarusich MF, Robinson BH, Taanman JW, Kim SJ, Schillace R, Smith JL, Capaldi RA
JournalBiochim Biophys Acta
PubMed ID9540845
Although much progress has been made in identifying genetic defects associated with mitochondrial diseases, the protein expression patterns of most disorders are poorly understood. Here we use immunochemical techniques to describe subunit expression patterns of respiratory chain enzyme complexes II (succinate dehydrogenase: SD) and IV (cytochrome c oxidase: COX) in ... More
Molecular mechanisms in mitochondrial DNA depletion syndrome.
AuthorsTaanman JW, Bodnar AG, Cooper JM, Morris AA, Clayton PT, Leonard JV, Schapira AH
JournalHum Mol Genet
PubMed ID9175742
Depletion of mitochondrial DNA (mtDNA) appears to be an important cause of mitochondrial dysfunction in neonates and infants. We have identified another child in whom depletion of mtDNA was demonstrated in liver and serial skeletal muscle biopsies. A primary myoblast culture from the patient initially showed normal levels of mtDNA, ... More
Cytochrome C oxidase activity and oxygen tolerance.
AuthorsCampian JL, Gao X, Qian M, Eaton JW
JournalJ Biol Chem
PubMed ID17303578
Most cultured cells and intact animals die under hyperoxic conditions. However, a strain of HeLa cells that proliferates under 80% O(2), termed "HeLa-80," has been derived from wildtype HeLa cells ("HeLa-20") by selection for resistance to stepwise increases of oxygen partial pressure. The tolerance of HeLa-80 cells to hyperoxia is ... More
Subunit specific monoclonal antibodies show different steady-state levels of various cytochrome-c oxidase subunits in chronic progressive external ophthalmoplegia.
AuthorsTaanman JW, Burton MD, Marusich MF, Kennaway NG, Capaldi RA
JournalBiochim Biophys Acta
PubMed ID8611660
Monoclonal antibodies recognizing the mitochondrially encoded subunits I and II, and the nuclear-encoded subunits IV, Va, Vb and VIc of human cytochrome-c oxidase were generated. These antibodies are highly specific and allow the assessment of subunit steady-state levels in crude cell extracts and tissue sections. In the experimental human cell ... More
Variations in the subunit content and catalytic activity of the cytochrome c oxidase complex from different tissues and different cardiac compartments.
AuthorsVijayasarathy C, Biunno I, Lenka N, Yang M, Basu A, Hall IP, Avadhani NG
JournalBiochim Biophys Acta
PubMed ID9565657
The composition and activity of cytochrome c oxidase (COX) was studied in mitochondria from rat liver, brain, kidney and heart and also in different compartments of the bovine heart to see whether any correlation exists between known oxidative capacity and COX activity. Immunoblot analysis showed that the levels of ubiquitously ... More
Hypothyroid phenotype is contributed by mitochondrial complex I inactivation due to translocated neuronal nitric-oxide synthase.
Although transcriptional effects of thyroid hormones have substantial influence on oxidative metabolism, how thyroid sets basal metabolic rate remains obscure. Compartmental localization of nitric-oxide synthases is important for nitric oxide signaling. We therefore examined liver neuronal nitric-oxide synthase-alpha (nNOS) subcellular distribution as a putative mechanism for thyroid effects on rat ... More