title: Comparative profiling of the mammalian mitochondrial proteome: multiple aconitase-2 isoforms including N-formylkynurenine modifications as part of a protein biomarker signature for reactive oxidative species.
abstract: The activity of mitochondria induces, as a byproduct, a variety of post-translational modifications in associated proteins, which have functional downstream consequences for processes such as apoptosis, autophagy, and plasticity; e.g., reactive oxygen species (ROS), which induce N-formyl-kynurenine from oxidized tryptophans in certain mitochondrial proteins which are localized in close spatial proximity to their source. This type of fast molecular changes has profound influence on cell death and survival with implications in a number of pathologies. The quantitative and differential analysis of bovine heart mitochondria by four 2D-PAGE methods, including 2D-PAGE with high-resolution IEF as first dimension, revealed that due to limited resolution, those methods employing blue native-, tricine-urea-, and 16-BAC-PAGE as the first dimension are less applicable for the differential quantitative analysis of redundant protein spots which might give insight into post-translational modifications that are relevant in age- and stress-related changes. Moreover, 2D-PAGE with high resolution IEF was able to resolve a surprisingly large number of membrane proteins from mitochondrial preparations. For aconitase-2, an enzyme playing an important role in mitochondrial aging, a more thorough molecular analysis of all separable isoforms was performed, leading to the identification of two particular N-formylkynurenine modifications. Next to protein redundancy, native protein-protein interactions, with the potential of relating certain post-translational modification patterns to distinct oligomeric states, e.g., oxidative phosphorylation super complexes, might provide novel and (patho-) physiologically relevant information. Among proteins identified, 14 new proteins (GenBank entries), previously not associated with mitochondria, were found.
authors.affiliation: ProteoSys AG, Carl Zeiss Strasse 51, 55129 Mainz, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Hunzinger
authors.forename: Wojciech
authors.initials: W
authors.lastname: Wozny
authors.forename: Gerhard P
authors.initials: GP
authors.lastname: Schwall
authors.forename: Slobodan
authors.initials: S
authors.lastname: Poznanović
authors.forename: Werner
authors.initials: W
authors.lastname: Stegmann
authors.forename: Helmut
authors.initials: H
authors.lastname: Zengerling
authors.forename: Rainer
authors.initials: R
authors.lastname: Schoepf
authors.forename: Karlfried
authors.initials: K
authors.lastname: Groebe
authors.forename: Michael A
authors.initials: MA
authors.lastname: Cahill
authors.forename: Heinz D
authors.initials: HD
authors.lastname: Osiewacz
authors.forename: Nora
authors.initials: N
authors.lastname: Jägemann
authors.forename: Monika
authors.initials: M
authors.lastname: Bloch
authors.forename: Norbert A
authors.initials: NA
authors.lastname: Dencher
authors.forename: Frank
authors.initials: F
authors.lastname: Krause
authors.forename: André
authors.initials: A
authors.lastname: Schrattenholz
mesh_terms: D000154:Aconitate Hydratase / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002417:Cattle; D020869:Gene Expression Profiling; D006801:Humans; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D007737:Kynurenine / Q000031:analogs & derivatives* / Q000737:chemistry; D008929:Mitochondria, Heart / Q000201:enzymology*; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D007527:Isoenzymes; D017382:Reactive Oxygen Species; C007772:N'-formylkynurenine; D007737:Kynurenine; C476079:ACO2 protein, human; D000154:Aconitate Hydratase