The YTA10–12 Complex, an AAA Protease with Chaperone-like Activity in the Inner Membrane of Mitochondria

• Published in: Cell Vol. 85; no. 6; pp. 875 - 885
• Main Authors: Arlt, Heike, Tauer, Raimund, Feldmann, Horst, Neupert, Walter, Langer, Thomas
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 14-06-1996
• Subjects: Adenosine Triphosphatases - analysis; Adenosine Triphosphatases - biosynthesis; Adenosine Triphosphatases - chemistry; Adenosine Triphosphatases - isolation & purification; Adenosine Triphosphatases - metabolism; Adenosine Triphosphate - metabolism; Cell Membrane - enzymology; Fungal Proteins - analysis; Fungal Proteins - chemistry; Fungal Proteins - isolation & purification; Fungal Proteins - metabolism; Hydrolysis; Membrane Proteins - analysis; Membrane Proteins - chemistry; Membrane Proteins - isolation & purification; Membrane Proteins - metabolism; Metalloendopeptidases - chemistry; Metalloendopeptidases - isolation & purification; Metalloendopeptidases - metabolism; Mitochondria - enzymology; Mitochondrial Proteins; Molecular Chaperones - chemistry; Molecular Chaperones - isolation & purification; Molecular Chaperones - metabolism; Molecular Weight; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Substrate Specificity
• ISSN: 0092-8674; 1097-4172
• DOI: 10.1016/S0092-8674(00)81271-4

The mitochondrial members of the highly conserved AAA family, Yta10p and Yta12p, constitute a membrane-embedded complex of about 850 kDa. As an ATP dependent metallopeptidase (AAA protease), the YTA10–12 complex mediates the degradation of nonassembled inner membrane proteins. In contrast to nucleotide-dependent complex formation and substrate binding, proteolysis of bound polypeptides depends on the hydrolysis of ATP and the metallopeptidase activity of both subunits. Independent of its proteolytic function, the chaperone-like activity of the YTA10–12 complex is required for assembly of the membrane-associated ATP synthase. We propose that proteolytic and chaperone-like activities in the YTA10–12 complex mediate assembly and degradation processes of membrane protein complexes and thereby exert key functions in the maintenance of membrane integrity.