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Mitochondrial DNA somatic mutations (point mutations and large deletions) and mitochondrial DNA variants in human thyroid pathology -: A study with emphasis on Hurthle cell tumors

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AMERICAN JOURNAL OF PATHOLOGY 2002年第5期160卷 1857-1865页

作者： Máximo, V Soares, P Lima, J Cameselle-Teijeiro, J Sobrinho-Simoes, M Univ Porto Inst Mol Pathol & Immunol P-4100 Oporto Portugal Fac Med Porto Dept Pathol Oporto Portugal Hosp Sao Joao Dept Pathol Oporto Portugal Univ Santiago de Compostela Hosp Clin Dept Pathol Santiago De Compostela Spain

In an attempt to progress in the understanding of the relationship of mitochondrial DNA (mtDNA) alterations and thyroid tumorigenesis, we studied the mtDNA in 79 benign and malignant tumors (43 Hurthle and 36 non-Hurthle cell neoplasms) and respective normal parenchyma. The mtDNA common deletion (CD) was evaluated by semiquantitative polymerase chain reaction. Somatic point mutations and sequence variants of mtDNA were searched for in 66 tumors (59 patients) and adjacent parenchyma by direct sequencing of 70% of the mitochondrial genome (including all of the 13 OXPHOS system genes). We detected 57 somatic mutations, mostly transitions, in 34 tumors and 253 sequence variants in 59 patients. Follicular and papillary carcinomas carried a significantly higher prevalence of nonsilent point mutations of complex I genes than adenomas. We also detected a significantly higher prevalence of complex I and complex IV sequence variants in the normal parenchyma adjacent to the malignant tumors. Every Hurthle cell tumor displayed a relatively high percentage (up to 16%) of mtDNA CD independently of the lesion's histotype. The percentage of deleted mtDNA molecules was significantly higher in tumors with D-loop mutations than in mtDNA stable tumors. Sequence variants of the ATPase 6 gene, one of the complex V genes thought to play a role in mtDNA maintenance and integrity in yeast, were significantly more prevalent in patients with Hurthle cell tumors than in patients with non-Hurthle cell neoplasms. We conclude that mtDNA variants and mtDNA somatic mutations of complex I and complex IV genes seem to be involved in thyroid tumorigenesis. Germline polymorphisms of the ATPase 6 gene are associated with the occurrence of mtDNA CD, the hallmark of Hurthle cell tumors.

关键词：腺瘤嗜酸粒细胞/遗传学腺瘤嗜酸粒细胞/病理学腺苷三磷酸酶类/遗传学碱基序列细胞色素b组/遗传学 DNA突变分析 DNA 线粒体/化学 DNA 线粒体/遗传学电子传递复合物Ⅰ 电子传递复合物ⅳ/遗传学基因频率突变 NADH NADPH氧化还原酶类/遗传学氧化磷酸化点突变序列缺失甲状腺/代谢甲状腺/病理学甲状腺肿瘤/遗传学甲状腺肿瘤/病理学成年人老年人儿童人类中年人

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Early-onset multisystem mitochondrial disorder caused by a nonsense mutation in the mitochondrial DNA cytochrome c oxidase II gene

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ANNALS OF NEUROLOGY 2001年第3期50卷 409-413页

作者： Campos, Y García-Redondo, A Fernández-Moreno, MA Martínez-Pardo, M Goda, G Rubio, JC Martín, MA del Hoyo, P Cabello, A Bornstein, B Garesse, R Arenas, J Univ Hosp Ctr Invest Madrid Spain Univ Hosp Dept Neuropatol Madrid Spain UAM CSIC Inst Invest Biomed Alberto Sols Madrid Spain Hosp Univ Ramon y Cajal Dept Pediat Madrid Spain

We report the first nonsense mutation (G7896A) in the mtDNA gene for subunit Il of cytochrome c oxidase (COX in a patient with early-onset multisystem disease and COX deficiency in muscle. The mutation was heteroplasmic in muscle, blood, and fibroblasts from the patient and abundantly present in COX-deficient fibers, but less abundant in COX-positive fibers;it was not found in blood samples from the patient's asymptomatic maternal relatives. Immunoblot analysis showed a reduced concentration of both COX II and COX I polypeptides, suggesting impaired assembly of COX holoenzyme.

关键词：密码子无义/遗传学 DNA 线粒体/生物合成 DNA 线粒体/遗传学电子传递复合物ⅳ/遗传学电子传递复合物Ⅳ/代谢线粒体肌病/酶学线粒体肌病/遗传学肌骨骼/酶学表型多态性限制性片段长度儿童学龄前女(雌)性人类

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Autocrine gastrins in colon cancer cells up-regulate cytochrome c oxidase Vb and down-regulate efflux of cytochrome c and activation of caspase-3

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JOURNAL OF BIOLOGICAL CHEMISTRY 2000年第42期275卷 32491-32498页

作者： Wu, H Rao, GN Dai, BS Singh, P Univ Texas Med Branch Dept Anat & Neurosci Galveston TX 77555 USA

Suppression of the gastrin gene in human colon cancer cells by stably expressing antisense (AS) gastrin RNA results in significant growth suppression of AS cells. To understand mechanisms mediating the growth effects of autocrine gastrins, differential expression of transcripts by AS and control (C) clones of a representative cell line (HCT-116) was analyzed to identify target genes of autocrine gastrins, Six differentially expressed transcripts were confirmed and sequenced. Of these, the RNA and protein levels of cytochrome c oxidase (COX) Vb were significantly higher in C versus AS cells. The expression of COX Vb by colon cancer cells was proportional to the expression of gastrin. Higher levels of COX Vb coprecipitated with cytochrome c in the mitochondria of C versus AS cells. Treatment of mitochondria with digitonin resulted in a a-fold higher release of cytochrome c from AS versus C mitochondria. As a corollary, the cytosolic levels of cytochrome c were significantly higher in AS versus C cells, which correlated with similar to2- and similar to3-fold higher activation of caspase-9 and -3, respectively, in AS versus C cells in response to camptothecin. Thus, autocrine gastrins may support growth/ survival of cells by up-regulating COX Vb, which may decrease the sensitivity of the cancer cells to apoptotic stimuli by increasing retention of cytochrome c in mitochondria.

关键词：结肠肿瘤细胞色素c组/分离和提纯细胞色素c组/代谢胞质溶胶/代谢电子传递复合物ⅳ/遗传学电子传递复合物Ⅳ/代谢胃泌素类/遗传学胃泌素类/生理学基因表达调控酶学/生理学基因表达调控肿瘤/生理学线粒体/酶学线粒体/遗传学 RNA 反义/遗传学 RNA 反义/药理学转录遗传/生理学肿瘤细胞培养的人类

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Detection of the mitochondrially encoded cytochrome c oxidase subunit I in the trypanosomatid protozoan Leishmania tarentolae -: Evidence for translation of unedited mRNA in the kinetoplast

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JOURNAL OF BIOLOGICAL CHEMISTRY 2000年第22期275卷 17160-17165页

作者： Horváth, A Kingan, TG Maslov, DA Univ Calif Riverside Dept Biol Riverside CA 92521 USA Univ Calif Riverside Dept Entomol Riverside CA 92521 USA

With the aim of identification of kinetoplast-encoded proteins we investigated the subunit composition of cytochrome c oxidase (respiratory complex IV) from kinetoplast mitochondria of the trypanosomatid protozoan Leishmania tarentolae. Eleven stoichiometric subunits were visible in Coomassie-stained, two-dimensional Blue Native/Tricine-SDS electrophoretic gels. Their partial amino acid sequences indicated that these polypeptides are nuclear-encoded. The mitochondrial subunit I was detected with the polyclonal antibodies against an internal region of this polypeptide. In two-dimensional (9 versus 14%) polyacrylamide glycine-SDS gels this subunit is found as a series of spots located off the main diagonal, a property that can be explained by abnormal electrophoretic migration and aggregation. In gels loaded with high amounts of the purified, enzymatically active oxidase, the subunit I spots could be visualized by staining. The determined N-terminal amino acid sequence of the putative monomeric subunit I (MFXLCLVCLSVS) matched with the predicted sequence, thus indicating that the corresponding kinetoplast unedited mRNA is translated into a functional protein.

关键词：氨基酸序列细胞核/酶学电子传递复合物Ⅳ/化学电子传递复合物ⅳ/遗传学电子传递复合物Ⅳ/代谢电泳聚丙烯酰氨凝胶利什曼原虫属/酶学利什曼原虫属/遗传学分子序列数据蛋白质生物合成 RNA编辑 RNA 信使/遗传学动物

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Tracing the D-pathway in reconstituted site-directed mutants of cytochrome c oxidase from Paracoccus denitrificans

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BIOCHEMISTRY 2000年第23期39卷 6756-6762页

作者： Pfitzner, U Hoffmeier, K Harrenga, A Kannt, A Michel, H Bamberg, E Richter, OMH Ludwig, B Goethe Univ Frankfurt Inst Biochem Biozentrum D-60439 Frankfurt Germany Max Planck Inst Biophys Abt Mol Membranbiol D-60528 Frankfurt Germany Max Planck Inst Biophys Biophys Chem Abt D-60496 Frankfurt Germany

Heme-copper terminal oxidases use the free energy of oxygen reduction to establish a transmembrane proton gradient. While the molecular mechanism of coupling electron transfer to proton pumping is still under debate, recent structure determinations and mutagenesis studies have provided evidence for two pathways for protons within subunit I of this class of enzymes. Here, we probe the D-pathway by mutagenesis of the cytochrome c oxidase of the bacterium Paracoccus denitrificans;amino acid replacements were selected with the rationale of interfering with the hydrophilic lining of the pathway, in particular its assumed chain of water molecules. Proton pumping was assayed in the reconstituted vesicle system by a stopped-flow spectroscopic approach, allowing a reliable assessment of proton translocation efficiency even at low turnover rates. Several mutations at positions above the cytoplasmic pathway entrance (Asn 131, Asn 199) and at the periplasmic exit region (Asp 399) led to complete inhibition of proton pumping;one of these mutants, N13 ID, exhibited an ideal decoupled phenotype, with a turnover comparable to that of the wild-type enzyme. Since sets of mutations in other positions along the presumed course of the pathway showed normal proton translocation stoichiometries, we conclude that the D-pathway is too wide in most areas above positions 131/199 to be disturbed by single amino acid replacements.

关键词：细菌蛋白质类/遗传学细菌蛋白质类/代谢碳酰氰化物间-氯苯基腙/药理学电子转运电子传递复合物ⅳ/遗传学电子传递复合物Ⅳ/代谢动力学模型分子诱变定点副球菌脱氮/酶学副球菌脱氮/遗传学质子泵/遗传学质子泵/代谢光谱分析

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A pathogenic 15-base pair deletion in mitochondrial DNA-encoded cytochrome c oxidase subunit III results in the absence of functional cytochrome c oxidase

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JOURNAL OF BIOLOGICAL CHEMISTRY 2000年第18期275卷 13994-14003页

作者： Hoffbuhr, KC Davidson, E Filiano, BA Davidson, M Kennaway, NG King, MP Thomas Jefferson Univ Dept Mol Pharmacol & Biochem Philadelphia PA 19107 USA Oregon Hlth Sci Univ Dept Mol & Med Genet Portland OR 97201 USA Columbia Univ Coll Phys & Surg Dept Neurol New York NY 10032 USA

A 15-base pair, in-frame, deletion (9480del15) in the mitochondrial DNA (mtDNA)-encoded cytochrome c oxidase subunit III (COX III) gene was identified previously in a patient with recurrent episodes of myoglobinuria and an isolated COX deficiency. Transmitochondrial cell lines harboring 0, 97, and 100% of the 9480del15 deletion were created by fusing human cells lacking mtDNA (rho(o) cells) with platelet and lymphocyte fractions isolated from the patient. The COX III gene mutation resulted in a severe respiratory chain defect in all mutant cell lines. Cells homoplasmic for the mutation had no detectable COX activity or respiratory ATP synthesis, and required uridine and pyruvate supplementation for growth, a phenotype similar to rho(o) cells. The cells with 97% mutated mtDNA exhibited severe reductions in both COX activity (6% of wild-type levels) and rates of ATP synthesis (9% of wild-type). The COX III polypeptide in the mutant cells, although translated at rates similar to wild-type, had reduced stability. There was no evidence for assembly of COX I, COX II, or COX III subunits in a multisubunit complex in cells homoplasmic for the mutation, thus indicating that there was no stable assembly of COX I with COX II in the absence of wild-type COX III. In contrast, the COX I and COX II subunits were assembled in cells with 97% mutated mtDNA.

关键词： DNA 线粒体/遗传学电子传递复合物ⅳ/遗传学电子传递复合物Ⅳ/代谢序列缺失肿瘤细胞培养的人类

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Effects of aging on mitochondrial DNA copy number and cytochrome c oxidase gene expression in rat skeletal muscle, liver, and heart

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JOURNAL OF BIOLOGICAL CHEMISTRY 2000年第5期275卷 3343-3347页

作者： Barazzoni, R Short, KR Nair, KS Mayo Clin & Mayo Fdn Endocrine Res Unit Rochester MN 55905 USA

Mitochondrial DNA (mtDNA) deletions and mutations have been reported to occur with aging in various tissues. To determine the functional impact of these changes, we measured mtDNA copy number, mitochondria-encoded cytochrome c oxidase (COX) subunit I and III transcript levels, and COX enzyme activity in skeletal muscles (medial and lateral gastrocnemius and soleus), liver, and heart in 6- and 27-month-old rats. Substantial age-related reductions of mtDNA copy number occurred in skeletal muscle groups (-23-40%, p < 0.03) and liver (-50%, p < 0.01) but not in the heart. The decline in mtDNA was not associated with reduced COX transcript levels in tissues with high oxidative capacities such as red soleus muscle or liver, while transcript levels were reduced with aging in the less oxidative mixed fiber gastrocnemius muscle (-17-22%, p < 0.06), Consistent with transcript levels, COX activity also remained unchanged in aging liver and heart but declined with age in the lateral gastrocnemius (-32%, p < 0.05). Thus, the effects of aging on mitochondrial gene expression are tissue-specific. A substantial age-related decline in mtDNA copy number proportional to tissue oxidative capacities is demonstrated in skeletal muscle and liver. mtDNA levels are in contrast preserved in the aging heart muscle, presumably due to its incessant aerobic activity. Reduced mtDNA copy number has no major effects on mitochondrial encoded transcript levels and enzyme activities in various tissues under these baseline study conditions. In contrast, maintenance of mitochondrial transcript levels that may be linked to oxidative metabolism and energy demand appears to be the main determinant of mitochondrial oxidative capacity in aging tissues.

关键词：衰老/生理学 DNA 线粒体/遗传学电子传递复合物ⅳ/遗传学基因表达/生理学心脏/生理学肝/生理学肌骨骼/生理学大鼠近交F344 动物男(雄)性大鼠

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Prion-dependent switching between respiratory competence and deficiency in the yeast nam9-1 mutant

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MOLECULAR AND CELLULAR BIOLOGY 2000年第19期20卷 7220-7229页

作者： Chacinska, A Boguta, M Krzewska, J Rospert, S MPI Enzymol Prot Folding Biozentrum Halle D-06120 Halle Germany Inst Biochem & Biophys PL-02106 Warsaw Poland Univ Gdansk Fac Biotechol PL-80822 Gdansk Poland Univ Basel Biozentrum CH-4056 Basel Switzerland

Nam9p is a protein of the mitochondrial ribosome. The respiration-deficient Saccharomyces cerevisiae strain MB43-nam9-1 expresses Nam9-1p containing the point mutation S82L. Respiratory deficiency correlates with a decrease in the steady level of some mitochondrially encoded proteins and the complete lack of mitochondrially encoded cytochrome oxidase subunit 2 (Cox2). De novo synthesis of Cod in MB43-nam9-1 is unaffected, indicating that newly synthesized Cox2 is rapidly degraded. Respiratory deficiency of MB43-nam9-1 is overcome by transient overexpression of HSP104, by deletion of HSP104, by transient exposure to guanidine hydrochloride, and by expression of the C-terminal portion of Sup35, indicating an involvement of the yeast prion [PSI+]. Respiratory deficiency of MB43-nam9-1 can be reinduced by transfer of cytosol from S. cerevisiae that harbors [PSI+]. We conclude that nam9-1 causes respiratory deficiency only in combination with the cytosolic prion [PSI+], presenting the first example of a synthetic effect between cytosolic [PSI+] and a mutant mitochondrial protein.

关键词：胞质溶胶/代谢 DNA 真菌/遗传学 DNA 线粒体/遗传学电子传递复合物ⅳ/遗传学电子传递复合物Ⅳ/代谢真菌蛋白质类/化学真菌蛋白质类/遗传学真菌蛋白质类/生理学基因缺失胍/药理学热休克蛋白质类/缺乏热休克蛋白质类/遗传学热休克蛋白质类/生理学线粒体/生理学核蛋白质类氧耗量/药物作用肽终止因子表型植物蛋白质类/遗传学植物蛋白质类/代谢点突变朊病毒/遗传学朊病毒/生理学蛋白质生物合成阻遏蛋白质类核糖体蛋白质类/遗传学核糖体蛋白质类/生理学酿酒酵母菌/遗传学酿酒酵母菌/代谢酿酒酵母蛋白质类

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Phylogenetic relationships and climatic adaptations in the Drosophila takahashii and montium species subgroups

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MOLECULAR PHYLOGENETICS AND EVOLUTION 2000年第1期15卷 147-156页

作者： Goto, SG Kitamura, HW Kimura, MT Hokkaido Univ Grad Sch Environm Earth Sci Sapporo Hokkaido 0600810 Japan

We analyze phylogenetic relationships among temperate, subtropical highland, and subtropical lowland species of the Drosophila takahashii and montium species subgroups based on sequence data of COI and Gpdh genes and discuss the evolution of temperate species in these subgroups with reference to their climatic adaptations. In the takahashii subgroup, D. lutescens (the temperate species) branched off first in the tree based on the combined data set, but D. prostipennis (the subtropical highland species) branched off first in the trees based on single genes. Thus, phylogenetic relationships in this subgroup are still ambiguous. In the montium subgroup, the cool-temperate species are phylogenetically close to the warm-temperate species, and these cool- and warm-temperate species form a cluster with the subtropical highland species. This suggests that perhaps the cool-temperate species derived from the warm-temperate species and the warm-temperate species derived from the subtropical highland species. In comparison with the subtropical lowland species, the subtropical highland species may be better able to colonize temperate areas since, as in the temperate species, they have an ability to develop their ovaries at moderately low temperature. However, the subtropical highland species, as well as the subtropical lowland species, were much less cold tolerant than the temperate species. Therefore, considerable genetic reformation would be required for both the subtropical highland and the subtropical lowland species to adapt to temperate climates, (C) 2000 Academic Press.

关键词：习服/遗传学冷 DNA/化学 DNA/遗传学果蝇属/分类果蝇属/遗传学果蝇属/生长和发育电子传递复合物ⅳ/遗传学甘油-3-磷酸脱氢酶(NAD+) 甘油磷酸脱氢酶/遗传学分子序列数据卵巢/生长和发育光照期种系发生序列分析 DNA 温度动物女(雌)性男(雄)性

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Resolving phylogeny at the family level by mitochondrial cytochrome oxidase sequences:: Phylogeny of carrion beetles (Coleoptera, Silphidae)

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MOLECULAR PHYLOGENETICS AND EVOLUTION 2000年第3期15卷 390-402页

作者： Dobler, S Müller, JK Univ Freiburg Inst Zool D-79104 Freiburg Germany

We investigated the phylogenetic relationships of carrion beetles (Coleoptera, Silphidae) using 2094 bp of their mitochondrial cytochrome oxidase subunit I and II and tRNA leucine gene sequences. Shorter fragments of this gene region previously have been used to establish generic relationships in insects. In this study, they provided more than sufficient resolution, although the third positions of the protein-coding sequences reached saturation for the deeper divergences. This first published phylogeny for the Silphidae comprises 23 species from 13 genera sampled across the geographic range of the family. In addition, we included species from three related families as outgroups. One of these families, the Agyrtidae, was, until recently, included in the Silphidae, but its resolution here justifies its current position as a separate family. The silphid subfamilies Nicrophorinae and Silphinae are monophyletic in all analyses. All genera for which several species were sampled are supported as monophyletic groups, with the exception of the genus Silpha. European and North American representatives of two Nicrophorus species described from both continents are supported as each others' closest relatives. The lineage that colonized Gondwanaland and that most likely originated in the Palearctic is the most basal within the Silphinae. (C) 2000 Academic Press.

关键词：碱基序列甲虫/分类甲虫/遗传学 DNA 线粒体/遗传学电子传递复合物ⅳ/遗传学似然函数分子序列数据种系发生 RNA 转移/代谢序列分析 DNA 序列同源性氨基酸序列同源性核酸动物

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