title: Complexome profiling identifies TMEM126B as a component of the mitochondrial complex I assembly complex.
abstract: Macromolecular complexes are essential players in numerous biological processes. They are often large, dynamic, and rather labile; approaches to study them are scarce. Covering masses up to ∼30 MDa, we separated the native complexome of rat heart mitochondria by blue-native and large-pore blue-native gel electrophoresis to analyze its constituents by mass spectrometry. Similarities in migration patterns allowed hierarchical clustering into interaction profiles representing a comprehensive analysis of soluble and membrane-bound complexes of an entire organelle. The power of this bottom-up approach was validated with well-characterized mitochondrial multiprotein complexes. TMEM126B was found to comigrate with known assembly factors of mitochondrial complex I, namely CIA30, Ecsit, and Acad9. We propose terming this complex mitochondrial complex I assembly (MCIA) complex. Furthermore, we demonstrate that TMEM126B is required for assembly of complex I. In summary, complexome profiling is a powerful and unbiased technique allowing the identification of previously overlooked components of large multiprotein complexes.
authors.affiliation: Molecular Bioenergetics Group, Medical School, Cluster of Excellence Frankfurt Macromolecular Complexes, Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
authors.forename: Heinrich
authors.initials: H
authors.lastname: Heide
authors.forename: Lea
authors.initials: L
authors.lastname: Bleier
authors.forename: Mirco
authors.initials: M
authors.lastname: Steger
authors.forename: Jörg
authors.initials: J
authors.lastname: Ackermann
authors.forename: Stefan
authors.initials: S
authors.lastname: Dröse
authors.forename: Bettina
authors.initials: B
authors.lastname: Schwamb
authors.forename: Martin
authors.initials: M
authors.lastname: Zörnig
authors.forename: Andreas S
authors.initials: AS
authors.lastname: Reichert
authors.forename: Ina
authors.initials: I
authors.lastname: Koch
authors.forename: Ilka
authors.initials: I
authors.lastname: Wittig
authors.forename: Ulrich
authors.initials: U
authors.lastname: Brandt
mesh_terms: D000818:Animals; D030562:Databases, Protein; D015180:Electrophoresis, Gel, Two-Dimensional; D057809:HEK293 Cells; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D008929:Mitochondria, Heart / Q000378:metabolism; D046912:Multiprotein Complexes / Q000737:chemistry / Q000378:metabolism*; D040901:Proteomics; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D008565:Membrane Proteins; D046912:Multiprotein Complexes; D034741:RNA, Small Interfering; C578691:TMEM126B protein, rat