chaperonin / Huntington's disease / protein aggregation
機能・相同性
機能・相同性情報
positive regulation of protein localization to Cajal body / positive regulation of telomerase RNA localization to Cajal body / chaperonin-containing T-complex / : / BBSome-mediated cargo-targeting to cilium / Formation of tubulin folding intermediates by CCT/TriC / Folding of actin by CCT/TriC / binding of sperm to zona pellucida / Prefoldin mediated transfer of substrate to CCT/TriC / beta-tubulin binding ...positive regulation of protein localization to Cajal body / positive regulation of telomerase RNA localization to Cajal body / chaperonin-containing T-complex / : / BBSome-mediated cargo-targeting to cilium / Formation of tubulin folding intermediates by CCT/TriC / Folding of actin by CCT/TriC / binding of sperm to zona pellucida / Prefoldin mediated transfer of substrate to CCT/TriC / beta-tubulin binding / Association of TriC/CCT with target proteins during biosynthesis / : / positive regulation of telomere maintenance via telomerase / protein folding chaperone / mRNA 3'-UTR binding / ATP-dependent protein folding chaperone / response to virus / mRNA 5'-UTR binding / Cooperation of PDCL (PhLP1) and TRiC/CCT in G-protein beta folding / unfolded protein binding / G-protein beta-subunit binding / protein folding / cell body / microtubule / protein stabilization / centrosome / ATP hydrolysis activity / extracellular exosome / ATP binding / cytosol 類似検索 - 分子機能
ジャーナル: J Biol Chem / 年: 2014 タイトル: Biochemical characterization of mutants in chaperonin proteins CCT4 and CCT5 associated with hereditary sensory neuropathy. 著者: Oksana A Sergeeva / Meme T Tran / Cameron Haase-Pettingell / Jonathan A King / 要旨: Hereditary sensory neuropathies are a class of disorders marked by degeneration of the nerve fibers in the sensory periphery neurons. Recently, two mutations were identified in the subunits of the ...Hereditary sensory neuropathies are a class of disorders marked by degeneration of the nerve fibers in the sensory periphery neurons. Recently, two mutations were identified in the subunits of the eukaryotic cytosolic chaperonin TRiC, a protein machine responsible for folding actin and tubulin in the cell. C450Y CCT4 was identified in a stock of Sprague-Dawley rats, whereas H147R CCT5 was found in a human Moroccan family. As with many genetically identified mutations associated with neuropathies, the underlying molecular basis of the mutants was not defined. We investigated the biochemical properties of these mutants using an expression system in Escherichia coli that produces homo-oligomeric rings of CCT4 and CCT5. Full-length versions of both mutant protein chains were expressed in E. coli at levels approaching that of the WT chains. Sucrose gradient centrifugation revealed chaperonin-sized complexes of both WT and mutant chaperonins, but with reduced recovery of C450Y CCT4 soluble subunits. Electron microscopy of negatively stained samples of C450Y CCT4 revealed few ring-shaped species, whereas WT CCT4, H147R CCT5, and WT CCT5 revealed similar ring structures. CCT5 complexes were assayed for their ability to suppress aggregation of and refold the model substrate γd-crystallin, suppress aggregation of mutant huntingtin, and refold the physiological substrate β-actin in vitro. H147R CCT5 was not as efficient in chaperoning these substrates as WT CCT5. The subtle effects of these mutations are consistent with the homozygous disease phenotype, in which most functions are carried out during development and adulthood, but some selective function is lost or reduced.