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
Identification of mouse Prp19p as a lipid droplet-associated protein and its possible involvement in the biogenesis of lipid droplets.
AuthorsCho SY, Shin ES, Park PJ, Shin DW, Chang HK, Kim D, Lee HH, Lee JH, Kim SH, Song MJ, Chang IS, Lee OS, Lee TR
JournalJ Biol Chem
PubMed ID17118936
'Prp19p is an integral component of the heteromeric protein complex (the NineTeen complex) in the nucleus, and it is essential for the structural integrity of NineTeen complex and its subsequent activation of the spliceosome. We identified Prp19p, which has never been reported in relation to any function outside of the ... More
Asbestos increases mammalian AP-endonuclease gene expression, protein levels, and enzyme activity in mesothelial cells.
'Only two DNA repair enzymes, DNA polymerase beta and O6-methylguanine-DNA methyltransferase, have been shown to be inducible in mammalian cells by genotoxic agents. We show here that crocidolite asbestos induces the DNA repair enzyme, apurinic/apyrimidinic (AP)-endonuclease, in isolated mesothelial cells, the progenitor cells of malignant mesothelioma. Asbestos at nontoxic concentrations ... 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
Calcineurin regulates skeletal muscle metabolism via coordinated changes in gene expression.
AuthorsLong YC, Glund S, Garcia-Roves PM, Zierath JR
JournalJ Biol Chem
PubMed ID17107952
'The metabolic property of skeletal muscle adapts in response to an increased physiological demand by altering substrate utilization and gene expression. The calcium-regulated serine/threonine protein phosphatase calcineurin has been implicated in the transduction of motor neuron signals to alter gene expression programs in skeletal muscle. We utilized transgenic mice that ... More
Desmin cytoskeleton linked to muscle mitochondrial distribution and respiratory function.
AuthorsMilner DJ, Mavroidis M, Weisleder N, Capetanaki Y
JournalJ Cell Biol
PubMed ID10995435
'Ultrastructural studies have previously suggested potential association of intermediate filaments (IFs) with mitochondria. Thus, we have investigated mitochondrial distribution and function in muscle lacking the IF protein desmin. Immunostaining of skeletal muscle tissue sections, as well as histochemical staining for the mitochondrial marker enzymes cytochrome C oxidase and succinate dehydrogenase, ... More
Targeting of NH2-terminal-processed microsomal protein to mitochondria: a novel pathway for the biogenesis of hepatic mitochondrial P450MT2.
'Cytochrome P4501A1 is a hepatic, microsomal membrane-bound enzyme that is highly induced by various xenobiotic agents. Two NH2-terminal truncated forms of this P450, termed P450MT2a and MT2b, are also found localized in mitochondria from beta-naphthoflavone-induced livers. In this paper, we demonstrate that P4501A1 has a chimeric NH2-terminal signal that facilitates ... More
Accumulation of mitochondrial P450MT2, NH(2)-terminal truncated cytochrome P4501A1 in rat brain during chronic treatment with beta-naphthoflavone. A role in the metabolism of neuroactive drugs.
AuthorsBoopathi E, Anandatheerthavarada HK, Bhagwat SV, Biswas G, Fang JK, Avadhani NG
JournalJ Biol Chem
PubMed ID10915793
'The biochemical and molecular characteristics of cytochrome P4501A1 targeted to rat brain mitochondria was studied to determine the generality of the targeting mechanism previously described for mitochondrial cytochrome P450MT2 (P450MT2) from rat liver. In rat brain and C6 glioma cells chronically exposed to beta-naphoflavone (BNF), P450MT2 content reached 50 and ... More
Chronic exposure to nitric oxide alters the free iron pool in endothelial cells: role of mitochondrial respiratory complexes and heat shock proteins.
AuthorsRamachandran A, Ceaser E, Darley-Usmar VM
JournalProc Natl Acad Sci U S A
PubMed ID14691259
'The mechanisms of nitric oxide (NO) signaling include binding to the iron centers in soluble guanylate cyclase and cytochrome c oxidase and posttranslational modification of proteins by S-nitrosation. Low levels of NO control mitochondrial number in cells, but little is known of the impact of chronic exposure to high levels ... More
Mitochondrial abnormalities in Alzheimer's disease.
AuthorsHirai K, Aliev G, Nunomura A, Fujioka H, Russell RL, Atwood CS, Johnson AB, Kress Y, Vinters HV, Tabaton M, Shimohama S, Cash AD, Siedlak SL, Harris PL, Jones PK, Petersen RB, Perry G, Smith MA
JournalJ Neurosci
PubMed ID11312286
'The finding that oxidative damage, including that to nucleic acids, in Alzheimer''s disease is primarily limited to the cytoplasm of susceptible neuronal populations suggests that mitochondrial abnormalities might be part of the spectrum of chronic oxidative stress of Alzheimer''s disease. In this study, we used in situ hybridization to mitochondrial ... 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
Cloning and characterization of AOEB166, a novel mammalian antioxidant enzyme of the peroxiredoxin family.
AuthorsKnoops B, Clippe A, Bogard C, Arsalane K, Wattiez R, Hermans C, Duconseille E, Falmagne P, Bernard A
JournalJ Biol Chem
PubMed ID10521424
Using two-dimensional electrophoresis, we have recently identified in human bronchoalveolar lavage fluid a novel protein, termed B166, with a molecular mass of 17kDa. Here, we report the cloning of human and rat cDNAs encoding B166, which has been renamed AOEB166 for antioxidant enzyme B166. Indeed, the deducedamino acid sequence reveals ... More
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
Regulation of cytochrome c oxidase activity by c-Src in osteoclasts.
AuthorsMiyazaki T, Neff L, Tanaka S, Horne WC, Baron R
JournalJ Cell Biol
PubMed ID12615910
The function of the nonreceptor tyrosine kinase c-Src as a plasma membrane-associated molecular effector of a variety of extracellular stimuli is well known. Here, we show that c-Src is also present within mitochondria, where it phosphorylates cytochrome c oxidase (Cox). Deleting the c-src gene reduces Cox activity, and this inhibitory ... 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
Rapid analysis of mitochondrial DNA depletion by fluorescence in situ hybridization and immunocytochemistry: potential strategies for HIV therapeutic monitoring.
AuthorsJanes MS, Hanson BJ, Hill DM, Buller GM, Agnew JY, Sherwood SW, Cox WG, Yamagata K, Capaldi RA
JournalJ Histochem Cytochem
PubMed ID15258176
Nucleoside reverse transcriptase inhibitors (NRTIs) have been a mainstay in the treatment of human immunodeficiency virus since the introduction of azidothymidine (AZT) in 1987. However, none of the current therapies can completely eradicate the virus, necessitating long-term use of anti-retroviral drugs to prevent viral re-growth. One of the side effects ... 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
An immunocytochemical approach to detection of mitochondrial disorders.
Mitochondrial disorders can lead to a confusing array of symptoms, which frequently makes a diagnosis difficult. Traditional approaches to such diagnoses are based on enzyme activity assays, with further characterization provided by genetic analysis. However, these methods require relatively large sample sizes, are time-consuming, labor-intensive, and show variability between laboratories. ... More
Dual targeting property of the N-terminal signal sequence of P4501A1. Targeting of heterologous proteins to endoplasmic reticulum and mitochondria.
Recent studies from our laboratory showed that the beta-naphthoflavone-inducible cytochrome P4501A1 is targeted to both the endoplasmic reticulum (ER) and mitochondria. In the present study, we have further investigated the ability of the N-terminal signal sequence (residues 1-44) of P4501A1 to target heterologous proteins, dihydrofolate reductase, and the mature portion ... More
Detection of mitochondrial DNA depletion in living human cells using PicoGreen staining.
AuthorsAshley N, Harris D, Poulton J
JournalExp Cell Res
PubMed ID15652355
Human mitochondria DNA (mtDNA) is arranged within the mitochondria into discrete DNA-protein complexes, termed nucleoids. The size of the human mitochondrial genome is less than that of yeast and is more difficult to visualise by fluorescent DNA stains such as DAPI and Hoescht. We have developed a simple yet effective ... More
Analysis of mitochondrial morphology and function with novel fixable fluorescent stains.
AuthorsPoot M, Zhang YZ, Krämer JA, Wells KS, Jones LJ, Hanzel DK, Lugade AG, Singer VL, Haugland RP
JournalJ Histochem Cytochem
PubMed ID8985128
Investigation of mitochondrial morphology and function has been hampered because photostable, mitochondrion-specific stains that are retained in fixed, permeabilized cells have not been available. We found that in live cell preparations, the CMXRos and H2-CMXRos dyes were more photostable than rhodamine 123. In addition, fluorescence and morphology of mitochondria stained ... More
Mechanism of cyclosporin-induced inhibition of intracellular collagen degradation.
AuthorsArora PD, Silvestri L, Ganss B, Sodek J, McCulloch CA
JournalJ Biol Chem
PubMed ID11278659
The immunosuppressant cyclosporin A (CsA) markedly inhibits collagen degradation by an intracellular phagocytic pathway in fibroblasts, an effect that can lead to massive gingival overgrowth. We used a collagen bead model of collagen phagocytosis to determine whether CsA inhibits internalization by blocking efflux of calcium from endoplasmic reticulum (ER) and ... 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
The ELF -97 phosphatase substrate provides a sensitive, photostable method for labelling cytological targets.
AuthorsParagas VB, Kramer JA, Fox C, Haugland RP, Singer VL
JournalJ Microsc
PubMed ID12000550
We compared fluorescent signals obtained with fluorescein conjugates and the ELF-97 (enzyme-labelled fluorescence) phosphatase substrate [2-(5'-chloro-2-phosphoryloxyphenyl)-6-chloro-4(3H)-quinazolinone] in labelling cytological structures requiring high spatial resolution. Enzymatic cleavage of the ELF-97 phosphatase substrate yields an extremely fine precipitate that remains well localized to the site of enzymatic activity. This precipitate fluoresces bright ... More
Mild protease treatment as a small-scale biochemical method for mitochondria purification and proteomic mapping of cytoplasm-exposed mitochondrial proteins.
AuthorsForner F, Arriaga EA, Mann M
JournalJ Proteome Res
PubMed ID17137329
Because of its importance in basic biology and medicine, great efforts are being devoted to unraveling of the genuine mitochondrial proteome, which is the dynamic protein complement that the organelle uses to maintain its structure and functionality. Several proteomic investigations have now clearly shown that all the purification approaches we ... More
The human lysyl-tRNA synthetase gene encodes both the cytoplasmic and mitochondrial enzymes by means of an unusual alternative splicing of the primary transcript.
AuthorsTolkunova E, Park H, Xia J, King MP, Davidson E
JournalJ Biol Chem
PubMed ID10952987
Two cDNAs encoding human lysyl-tRNA synthetase have been identified. One encodes the cytoplasmic form of the enzyme identified previously. The second cDNA contains the same sequence but with a 180-bp insertion at the 5'-end of the mRNA. This results in a predicted protein whose carboxyl 576 amino acids are identical ... More