Publication Date:
2006-06-10
Description:
Transport of metabolites across the mitochondrial inner membrane is highly selective, thereby maintaining the electrochemical proton gradient that functions as the main driving force for cellular adenosine triphosphate synthesis. Mitochondria import many preproteins via the presequence translocase of the inner membrane. However, the reconstituted Tim23 protein constitutes a pore remaining mainly in its open form, a state that would be deleterious in organello. We found that the intermembrane space domain of Tim50 induced the Tim23 channel to close. Presequences overcame this effect and activated the channel for translocation. Thus, the hydrophilic cis domain of Tim50 maintains the permeability barrier of mitochondria by closing the translocation pore in a presequence-regulated manner.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Meinecke, Michael -- Wagner, Richard -- Kovermann, Peter -- Guiard, Bernard -- Mick, David U -- Hutu, Dana P -- Voos, Wolfgang -- Truscott, Kaye N -- Chacinska, Agnieszka -- Pfanner, Nikolaus -- Rehling, Peter -- New York, N.Y. -- Science. 2006 Jun 9;312(5779):1523-6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Biophysik, Universitat Osnabruck, FB Biologie/Chemie, D-49034 Osnabruck, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16763150" target="_blank"〉PubMed〈/a〉
Keywords:
Cell Membrane Permeability
;
Liposomes
;
Membrane Transport Proteins/metabolism
;
Mitochondrial Membrane Transport Proteins/*metabolism
;
Mitochondrial Membranes/*metabolism
;
Protein Structure, Tertiary
;
Saccharomyces cerevisiae
;
Saccharomyces cerevisiae Proteins/*metabolism
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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