title: Mitochondrial AAA proteases--towards a molecular understanding of membrane-bound proteolytic machines.
abstract: Mitochondrial AAA proteases play an important role in the maintenance of mitochondrial proteostasis. They regulate and promote biogenesis of mitochondrial proteins by acting as processing enzymes and ensuring the selective turnover of misfolded proteins. Impairment of AAA proteases causes pleiotropic defects in various organisms including neurodegeneration in humans. AAA proteases comprise ring-like hexameric complexes in the mitochondrial inner membrane and are functionally conserved from yeast to man, but variations are evident in the subunit composition of orthologous enzymes. Recent structural and biochemical studies revealed how AAA proteases degrade their substrates in an ATP dependent manner. Intersubunit coordination of the ATP hydrolysis leads to an ordered ATP hydrolysis within the AAA ring, which ensures efficient substrate dislocation from the membrane and translocation to the proteolytic chamber. In this review, we summarize recent findings on the molecular mechanisms underlying the versatile functions of mitochondrial AAA proteases and their relevance to those of the other AAA+ machines.
authors: Institute for Genetics, Centre for Molecular Medicine (CMMC), Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Zülpicher Str. 47a, 50674 Cologne, Germany. Florian.Gerdes@uni-koeln.de
authors: Florian
authors: F
authors: Gerdes
authors: Takashi
authors: T
authors: Tatsuta
authors: Thomas
authors: T
authors: Langer
mesh_terms: D049069:ATP-Dependent Proteases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000818:Animals; D006801:Humans; D008928:Mitochondria / Q000201:enzymology* / Q000378:metabolism; D051336:Mitochondrial Membranes / Q000201:enzymology / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D019636:Neurodegenerative Diseases / Q000201:enzymology / Q000235:genetics; D017434:Protein Structure, Tertiary; D059748:Proteolysis
chemical_list: D024101:Mitochondrial Proteins; D049069:ATP-Dependent Proteases