Linked Life Data

19269308

Source:http://linkedlifedata.com/resource/pubmed/id/19269308

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2009-5-15
pubmed:abstractText
We have created and analyzed the properties of a yeast model of the human mitochondrial DNA T8993C mutation that has been associated with maternally-inherited Leigh syndrome and/or with neurogenic muscle weakness, ataxia and retinitis pigmentosa. This mutation changes a highly conserved leucine to proline in the Atp6p subunit of the ATP synthase, at position 156 in the human protein, position 183 in yeast. In vitro the yeast T8993C mitochondria showed a 40-50% decrease in the rate of ATP synthesis. The ATP-driven translocation of protons across the inner mitochondrial membrane was normal in the mutant and fully sensitive to oligomycin, an inhibitor of the ATP synthase proton channel. However under conditions of maximal ATP hydrolytic activity, using non-osmotically protected mitochondria, the mutant ATPase activity was poorly inhibited by oligomycin (by 40% versus 85% in wild type cells). These anomalies were attributed by BN-PAGE and mitochondrial protein synthesis analyses to a less efficient incorporation of Atp6p within the ATP synthase. Interestingly, the cytochrome c oxidase content was selectively decreased by 40-50% in T8993C yeast, apparently due to a reduced synthesis of its mitochondrially encoded Cox1p subunit. This observation further supports the existence of a control of cytochrome c oxidase expression by the ATP synthase in yeast mitochondria. Despite the ATPase deficiency, growth of the atp6-L183P mutant on respiratory substrates and the efficiency of oxidative phosphorylation were similar to that of wild type, indicating that the mutation did not affect the proton permeability of the mitochondrial inner membrane.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:volume
1793
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
817-24
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Biochemical consequences in yeast of the human mitochondrial DNA 8993T>C mutation in the ATPase6 gene found in NARP/MILS patients.
pubmed:affiliation
Institut de Biochimie et Génétique Cellulaires, CNRS/Université Victor Segalen Bordeaux2, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't