title: Molecular chaperone functions in protein folding and proteostasis.
abstract: The biological functions of proteins are governed by their three-dimensional fold. Protein folding, maintenance of proteome integrity, and protein homeostasis (proteostasis) critically depend on a complex network of molecular chaperones. Disruption of proteostasis is implicated in aging and the pathogenesis of numerous degenerative diseases. In the cytosol, different classes of molecular chaperones cooperate in evolutionarily conserved folding pathways. Nascent polypeptides interact cotranslationally with a first set of chaperones, including trigger factor and the Hsp70 system, which prevent premature (mis)folding. Folding occurs upon controlled release of newly synthesized proteins from these factors or after transfer to downstream chaperones such as the chaperonins. Chaperonins are large, cylindrical complexes that provide a central compartment for a single protein chain to fold unimpaired by aggregation. This review focuses on recent advances in understanding the mechanisms of chaperone action in promoting and regulating protein folding and on the pathological consequences of protein misfolding and aggregation.
authors.affiliation: Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
authors.forename: Yujin E
authors.initials: YE
authors.lastname: Kim
authors.forename: Mark S
authors.initials: MS
authors.lastname: Hipp
authors.forename: Andreas
authors.initials: A
authors.lastname: Bracher
authors.forename: Manajit
authors.initials: M
authors.lastname: Hayer-Hartl
authors.forename: F Ulrich
authors.initials: FU
authors.lastname: Hartl
mesh_terms: D006801:Humans; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism* / Q000502:physiology; D017510:Protein Folding; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism*; D057165:Proteostasis Deficiencies / Q000503:physiopathology*
chemical_list: D018832:Molecular Chaperones; D011506:Proteins; D020543:Proteome