title: Essential role of Isd11 in mitochondrial iron-sulfur cluster synthesis on Isu scaffold proteins.
abstract: Mitochondria are indispensable for cell viability; however, major mitochondrial functions including citric acid cycle and oxidative phosphorylation are dispensable. Most known essential mitochondrial proteins are involved in preprotein import and assembly, while the only known essential biosynthetic process performed by mitochondria is the biogenesis of iron-sulfur clusters (ISC). The components of the mitochondrial ISC-assembly machinery are derived from the prokaryotic ISC-assembly machinery. We have identified an essential mitochondrial matrix protein, Isd11 (YER048w-a), that is found in eukaryotes only. Isd11 is required for biogenesis of cellular Fe/S proteins and thus is a novel subunit of the mitochondrial ISC-assembly machinery. It forms a complex with the cysteine desulfurase Nfs1 and is required for formation of an Fe/S cluster on the Isu scaffold proteins. We conclude that Isd11 is an indispensable eukaryotic component of the mitochondrial machinery for biogenesis of Fe/S proteins.
authors.affiliation: Institut für Biochemie und Molekularbiologie, Universität Freiburg, Freiburg, Germany.
authors.forename: Nils
authors.initials: N
authors.lastname: Wiedemann
authors.forename: Eugen
authors.initials: E
authors.lastname: Urzica
authors.forename: Bernard
authors.initials: B
authors.lastname: Guiard
authors.forename: Hanne
authors.initials: H
authors.lastname: Müller
authors.forename: Christiane
authors.initials: C
authors.lastname: Lohaus
authors.forename: Helmut E
authors.initials: HE
authors.lastname: Meyer
authors.forename: Michael T
authors.initials: MT
authors.lastname: Ryan
authors.forename: Chris
authors.initials: C
authors.lastname: Meisinger
authors.forename: Ulrich
authors.initials: U
authors.lastname: Mühlenhoff
authors.forename: Roland
authors.initials: R
authors.lastname: Lill
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Pfanner
mesh_terms: D000595:Amino Acid Sequence; D013437:Carbon-Sulfur Lyases / Q000378:metabolism; D002467:Cell Nucleus / Q000737:chemistry / Q000378:metabolism; D003600:Cytosol / Q000737:chemistry / Q000378:metabolism; D004795:Enzyme Stability; D007506:Iron-Sulfur Proteins / Q000032:analysis / Q000096:biosynthesis*; D008928:Mitochondria / Q000737:chemistry / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D011487:Protein Conformation; D029701:Saccharomyces cerevisiae Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D013466:Sulfurtransferases
chemical_list: C121520:ISU1 protein, S cerevisiae; D007506:Iron-Sulfur Proteins; C508374:Isd11 protein, S cerevisiae; D024101:Mitochondrial Proteins; D029701:Saccharomyces cerevisiae Proteins; D013466:Sulfurtransferases; C115912:NFS1 protein, S cerevisiae; D013437:Carbon-Sulfur Lyases; C080546:cysteine desulfurase