Linked Life Data

9341162

Source:http://linkedlifedata.com/resource/pubmed/id/9341162

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
43
pubmed:dateCreated
1997-11-28
pubmed:abstractText
Single base substitutions of the mitochondrial genome are associated with a variety of metabolic disorders. The myopathy, encephalopathy, lactic acidosis, stroke-like episodes syndrome, most frequently associated with an A to G transition mutation at position 3243 of the mitochondrial tRNALeu(UUR) gene, is characterized by biochemical and structural alterations of mitochondria. To investigate the pathophysiology of the mutation, we established distinct Epstein-Barr virus-transformed B-cell lines for analyses that harbored 30-70% of the mutated genome. Interestingly, neither an alteration of the processing of primary transcripts nor a general impairment of individual mitochondrial protein subunit synthesis rates could be observed. Nevertheless a marked decrease of cytochrome-c oxidase activity and reduced content of mitochondrial encoded subunits in the assembled respiratory complex IV was recorded on the cell line harboring 70% mutated mtDNA. Quantitative analysis of incorporation rates of the amino acid leucine into newly synthesized mitochondrial proteins, representing the functionality of the tRNALeu(UUR) in protein biosynthesis, revealed a specific decrease of this amino acid in distinct mitochondrial translation products. This observation was supported by a variation in the proteolytic fingerprint pattern. Our results suggest that the malfunctioning mitochondrial tRNALeu(UUR) leads to an alteration of amino acid incorporation into the mitochondrially synthesized subunits of the oxidative phosphorylation system, thus altering it's structure and function.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
27189-96
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:9341162-B-Lymphocytes, pubmed-meshheading:9341162-Base Sequence, pubmed-meshheading:9341162-Cell Line, Transformed, pubmed-meshheading:9341162-Citrate (si)-Synthase, pubmed-meshheading:9341162-DNA, Mitochondrial, pubmed-meshheading:9341162-DNA Primers, pubmed-meshheading:9341162-Electron Transport Complex IV, pubmed-meshheading:9341162-Herpesvirus 4, Human, pubmed-meshheading:9341162-Humans, pubmed-meshheading:9341162-Kinetics, pubmed-meshheading:9341162-MELAS Syndrome, pubmed-meshheading:9341162-Macromolecular Substances, pubmed-meshheading:9341162-Mitochondria, pubmed-meshheading:9341162-Mutation, pubmed-meshheading:9341162-NADH Dehydrogenase, pubmed-meshheading:9341162-Oxidative Phosphorylation, pubmed-meshheading:9341162-Polymerase Chain Reaction, pubmed-meshheading:9341162-Protein Biosynthesis, pubmed-meshheading:9341162-RNA, Transfer, Leu, pubmed-meshheading:9341162-Reference Values, pubmed-meshheading:9341162-Succinate Cytochrome c Oxidoreductase, pubmed-meshheading:9341162-Succinate Dehydrogenase
pubmed:year
1997
pubmed:articleTitle
Pathophysiology of the MELAS 3243 transition mutation.
pubmed:affiliation
Wissenschaftliche Nachwuchsgruppe, Theodor Boveri Institut, Biozentrum der Bayerischen-Julius-Maximillians-Universität, Am Hubland, 97074 Würzburg, Federal Republic of Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't