Mitochondrial iron-sulfur protein biogenesis and human disease.
Work during the past 14 years has shown that mitochondria are the primary site for the biosynthesis of iron-sulfur (Fe/S) clusters. In fact, it is this process that renders mitochondria essential for viability of virtually all eukaryotes, because they participate in the synthesis of the Fe/S clusters of key nuclear and cytosolic proteins such as DNA polymerases, DNA helicases, and ABCE1 (Rli1), an ATPase involved in protein synthesis. As a consequence, mitochondrial function is crucial for nuclear DNA synthesis and repair, ribosomal protein synthesis, and numerous other extra-mitochondrial pathways including nucleotide metabolism and cellular iron regulation. Within mitochondria, the synthesis of Fe/S clusters and their insertion into apoproteins is assisted by 17 proteins forming the ISC (iron-sulfur cluster) assembly machinery. Biogenesis of mitochondrial Fe/S proteins can be dissected into three main steps: First, a Fe/S cluster is generated de novo on a scaffold protein. Second, the Fe/S cluster is dislocated from the scaffold and transiently bound to transfer proteins. Third, the latter components, together with specific ISC targeting factors insert the Fe/S cluster into client apoproteins. Disturbances of the first two steps impair the maturation of extra-mitochondrial Fe/S proteins and affect cellular and systemic iron homeostasis. In line with the essential function of mitochondria, genetic mutations in a number of ISC genes lead to severe neurological, hematological and metabolic diseases, often with a fatal outcome in early childhood. In this review we briefly summarize our current functional knowledge on the ISC assembly machinery, and we present a comprehensive overview of the various Fe/S protein assembly diseases.
Institut für Zytobiologie, Philipps-Universität Marburg, Robert-Koch-Str. 6, 35032 Marburg, Germany.
Oliver
O
Stehling
Institut für Zytobiologie, Philipps-Universität Marburg, Robert-Koch-Str. 6, 35032 Marburg, Germany.
Claudia
C
Wilbrecht
Institut für Zytobiologie, Philipps-Universität Marburg, Robert-Koch-Str. 6, 35032 Marburg, Germany; Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Str. 10, 35043 Marburg, Germany; LOEWE Zentrum für Synthetische Mikrobiologie SynMikro, Hans-Meerwein-Str., 35043 Marburg, Germany. Electronic address: Lill@staff.uni-marburg.de.
Roland
R
Lill
D000818:Animals; D005786:Gene Expression Regulation; D006706:Homeostasis; D006801:Humans; D007501:Iron / Q000378:metabolism; D007506:Iron-Sulfur Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008928:Mitochondria / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D028361:Mitochondrial Diseases / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D024101:Mitochondrial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018832:Molecular Chaperones / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D014176:Protein Biosynthesis
D007506:Iron-Sulfur Proteins; D024101:Mitochondrial Proteins; D018832:Molecular Chaperones; D007501:Iron
Genome integrity; Iron regulation; Iron–sulfur cluster; Mitochondrial ISC system