The INA complex facilitates assembly of the peripheral stalk of the mitochondrial F1Fo‐ATP synthase. (18th June 2014)

• Record Type: Journal Article
• Authors: Lytovchenko, Oleksandr; Naumenko, Nataliia; Oeljeklaus, Silke; Schmidt, Bernhard; von der Malsburg, Karina; Deckers, Markus; Warscheid, Bettina; van der Laan, Martin; Rehling, Peter
• Is Part Of: EMBO journal. Volume 33:Number 15(2014)
• Page Start: 1624
• Page End: 1638
• Publication Date: 2014-06-18
• Subjects: Molecular biology -- Periodicals; 572.805
• DOI: 10.15252/embj.201488076
• Languages: English
• ISSNs: 0261-4189

Abstract

<abstract abstract-type="main" id="embj201488076-abs-0001"> <title>Abstract</title> <p>Mitochondrial F₁F_o‐ATP synthase generates the bulk of cellular ATP. This molecular machine assembles from nuclear‐ and mitochondria‐encoded subunits. Whereas chaperones for formation of the matrix‐exposed hexameric F₁‐ATPase core domain have been identified, insight into how the nuclear‐encoded F₁‐domain assembles with the membrane‐embedded F_o‐region is lacking. Here we identified the INA complex (INAC) in the inner membrane of mitochondria as an assembly factor involved in this process. Ina22 and Ina17 are INAC constituents that physically associate with the F₁‐module and peripheral stalk, but not with the assembled F₁F_o‐ATP synthase. Our analyses show that loss of Ina22 and Ina17 specifically impairs formation of the peripheral stalk that connects the catalytic F₁‐module to the membrane embedded F_o‐domain. We conclude that INAC represents a matrix‐exposed inner membrane protein complex that facilitates peripheral stalk assembly and thus promotes a key step in the biogenesis of mitochondrial F₁F_o‐ATP synthase.</p> </abstract>