Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7-8
pubmed:dateCreated
2008-6-24
pubmed:abstractText
Mitochondrial F(1)F(0)-ATPase was studied in lymphocytes from patients with neuropathy, ataxia, and retinitis pigmentosa (NARP), caused by a mutation at leu-156 in the ATPase 6 subunit. The mutation giving the milder phenotype (Leu156Pro) suffered a 30% reduction in proton flux, and a similar loss in ATP synthetic activity. The more severe mutation (Leu156Arg) also suffered a 30% reduction in proton flux, but ATP synthesis was virtually abolished. Oligomycin sensitivity of the proton translocation through F(0) was enhanced by both mutations. We conclude that in the Leu156Pro mutation, rotation of the c-ring is slowed but coupling of ATP synthesis to proton flux is maintained, whereas in the Leu156Arg mutation, proton flux appears to be uncoupled. Modelling indicated that, in the Leu156Arg mutation, transmembrane helix III of ATPase 6 is unable to span the membrane, terminating in an intramembrane helix II-helix III loop. We propose that the integrity of transmembrane helix III is essential for the mechanical function of ATPase 6 as a stator element in the ATP synthase, but that it is not relevant for oligomycin inhibition.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:volume
1777
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
941-5
pubmed:meshHeading
pubmed:articleTitle
The study of the pathogenic mechanism of mitochondrial diseases provides information on basic bioenergetics.
pubmed:affiliation
Dipartimento di Biochimica G. Moruzzi, Via Irnerio, 48, Università di Bologna, Italy. giancarlo.solaini@unibo.it
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't