• Journal of Yeungnam Medical Science
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• v.16 no.1
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• pp.114-118
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• 1999

Leber's hereditary optic neuropathy(LHON) is an optic nerve disease that causes blindness and is associated with maternally inherited mitochondrial DNA(mt DNA) mutations. The most common mitochondrial DNA mutation among LHON patients is a point mutation at the nucleotide 11778 in the subunit 4 of complex I. In one 45-year old male LHON patient with bilateral optic neuropathy. we investigated the presence of a point mutation of mitochondrial DNA and identified a single guanine to adenine transition mutation in the mitochondrial DNA at nucleotide point 11778.

• Journal of Life Science
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• v.14 no.2
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• pp.296-300
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• 2004

We investigated feasibility of using the formalin-fixed and paraffin-embedded tissue to study mitochondrial mutations in the case that fresh or frozen tissue, or blood samples are not available. Four paraffin blocks of muscle biopsies in Korean MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) patients were chosen. Total DNA was extracted from these blocks for PCR/RFLP analysis, and sequencing was performed to study the most common mutation, A to G transition at nucleotide position 3243 underlying MELAS in the mitochondrial tRN $A^{Leu(UUR)}$ gene. We could identify the A to G mutation at nt.3243 in three MELAS patients. Our results show that the mitochondrial genome of our paraffin blocks is presumably in good condition. Our results are in accordance with the previous findings by other investigators that PCR allows molecular genetic analysis of paraffin-embedded tissues stored in most histopathology laboratories.s.

• Toxicological Research
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• v.30 no.4
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• pp.235-242
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• 2014

Cancer cells are known to drastically alter cellular energy metabolism. The Warburg effect has been known for over 80 years as pertaining cancer-specific aerobic glycolysis. As underlying molecular mechanisms are elucidated so that cancer cells alter the cellular energy metabolism for their advantage, the significance of the modulation of metabolic profiles is gaining attention. Now, metabolic reprogramming is becoming an emerging hallmark of cancer. Therapeutic agents that target cancer energy metabolism are under intensive investigation, but these investigations are mostly focused on the cytosolic glycolytic processes. Although mitochondrial oxidative phosphorylation is an integral part of cellular energy metabolism, until recently, it has been regarded as an auxiliary to cytosolic glycolytic processes in cancer energy metabolism. In this review, we will discuss the importance of mitochondrial respiration in the metabolic reprogramming of cancer, in addition to discussing the justification for using mitochondrial DNA somatic mutation as metabolic determinants for cancer sensitivity in glucose limitation.

• Interdisciplinary Bio Central
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• v.3 no.4
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• pp.16.1-16.8
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• 2011

Defects in mitochondrial DNA (mtDNA) cause many human diseases and are critical factors that contribute to aging. The mechanisms of maternally-inherited mtDNA mutations are well studied. However, the role of acquired mutations during the aging process is still poorly understood. The most plausible mechanism is that increased reactive oxygen species (ROS) may affect the opening of mitochondrial voltage dependent anion channel (VDAC) and thus results in damage to mtDNA. This review focuses on recent trends in mtDNA research and the mutations that appear to be associated with increased ROS.

• Journal of Genetic Medicine
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• v.1 no.1
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• pp.39-43
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• 1997

The mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is inherited maternally, in which the MTTL1*MELAS 3243 mutation has been most commonly found as a heteroplasmy of A to G point mutation in the $tRNA^{Leu(UUR)}$ gene. The MTTL1*MELAS 3271 mutation is known to be the second common mutation, though clinical features of both mutations are not remarkably different. Recently, a variety of minor mutations have been reported in patients with MELAS. In this study, major efforts have been made to investigate the allele frequency of major three mutations including MTTL1*MELAS 3243, 3252, 3271 in 10 Korean families with MELAS probands. The PCR and subsequent direct sequencing of the PCR product in the regions spanning these three mutation sites were employed to identify the mutation in each proband. All family members have been screened for the presence of these three mutations by PCR-RFLP assay using Apa I, Acc I and Bfr I restriction enzymes. The MTTL1*MELAS 3243 mutation was most commonly found (7 out of 10 families tested) followed by the MTTL1*MELAS 3271 which was identified in 1 out of 10 families. In the remaining 2 families none of three mutations were found, indicating the presence of either nuclear mutation or yet unidentified mitochondrial DNA mutation in these families.

• Annals of Clinical Neurophysiology
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• v.21 no.1
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• pp.57-60
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• 2019

Axonal Charcot-Marie-Tooth disease (CMT2) has most frequently been associated with mutations in the MFN2 gene. MFN2 encodes mitofusin 2, which is a mitochondrial fusion protein that plays an essential role in mitochondrial function. We report CMT2 in a Korean father and his son that manifested with gait difficulties and progressive atrophy of the lower legs. Molecular analysis revealed a novel heterozygous c.2096T>C (p.Leu699Pro) mutation in the exon 18 of MFN2 in both subjects. We suggest that this novel mutation in MFN2 is probably a pathogenic mutation for CMT2.

• The Journal of Pediatrics of Korean Medicine
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• v.13 no.2
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• pp.225-235
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• 1999

MELAS is the condition associated with mutant mtDNA that most closely mimics thrombotic cerebrovascular disease. Characteristic abnormalities are two. first, 'ragged-red fibers' in muscle biopsy. second, point mutation in the mitochondrial DNA analyses. The characteristic clinical presentations of MELAS are short stature, recurrent stroke like episodes, migraine-like headache, sensorineural hearng loss, glucose intolerance and neuropathy. We now report a case of MELAS syndrome having mitochondrial DNA mutation with an A to G transition at the 3,243rd position diagnosed in Chung-ang Hospital.

• Journal of Microbiology
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• v.35 no.3
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• pp.228-233
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• 1997

The MTF1 gene of Saccharomyces cerevisiae encodes a 43 kDa MITOCHONDRIAL RNA polymerase specificity factor which recognizes mitochondrial promoters to initiate correct transcription. To better understand structure-function of the MTF1 gene as well as the transcription mechanism of mitochondrial RNA polymerase, two cold-sensitive alleles of the MTF1 mutation were isolated by plasmid shuffling method after PCR-based random mutagenesis of the MTF1 gene. The mutation sites were analyzed by nucleotide sequencing. These cs phenotype mtf1 mutants were respiration competent on the nonfermentible glycerol medium at the permissive temperature, but incompetent at 13.deg.C. The cs phenotype allele of the MTF1, yJH147, encoded an L146P replacement. The other cs allele, yJH148, contained K179E and K214M double replacements. Mutations in both alleles were in a region of Mtflp which is located between domains with amino acid sequence similarities to conserved regions 2 and 3 of bacterial s factors.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1737-1742
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• 2015

Background: Mitochondrial DNA (mtDNA) mutations have been shown to be associated with cancer. This study explored whether mtDNA mutations enhance cholangiocarcinoma (CCA) development in individuals. Materials and Methods: The whole mitochondrial genome sequences of 25 CCA patient tissues were determined and compared to those of white blood cells from the corresponding individuals and 12 healthy controls. The mitochondrial genome was amplified using primers from Mitoseq and compared with the Cambridge Reference Sequence. Results: A total of 161 mutations were identified in CCA tissues and the corresponding white blood cells, indicating germline origins. Sixty-five (40%) were new. Nine mutations, representing those most frequently observed in CCA were tested on the larger cohort of 60 CCA patients and 55 controls. Similar occurrence frequencies were observed in both groups. Conclusions: While the correspondence between the cancer and mitochondrial genome mutation was low, it is of interest to explore the functions of the missense mutations in a larger cohort, given the possibility of targeting mitochondria for cancer markers and therapy in the future.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.91-92
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• 2000

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