Yokota S I, Yanagi H, Yura T, Kubota H
HSP Research Institute, Kyoto Research Park, Japan.
Eur J Biochem. 2000 Mar;267(6):1658-64. doi: 10.1046/j.1432-1327.2000.01157.x.
The chaperonin containing TCP-1 (CCT) is a molecular chaperone consisting of eight subunit species and assists in the folding of actin, tubulin and some other cytosolic proteins. We examined the stress response of CCT subunit proteins in mammalian cultured cells using chemical stressors that cause accumulation of unfolded proteins. Levels of CCT subunit proteins in HeLa cells were coordinately and transiently upregulated under continuous chemical stress with sodium arsenite. CCT subunit levels in several mammalian cell lines were also upregulated during recovery from chemical stress caused by sodium arsenite or a proline analogue, L-azetidine-2-carboxylic acid. Several unidentified proteins that were newly synthesized and associated with CCT were found to increase concomitantly with CCT subunits themselves and known substrates during recovery from the stress. These results suggest that CCT plays important roles in the recovery of cells from protein damage by assisting in the folding of proteins that are actively synthesized and/or renatured during this period.
含TCP-1的伴侣蛋白（CCT）是一种由八个亚基组成的分子伴侣，可协助肌动蛋白、微管蛋白及其他一些胞质蛋白进行折叠。我们使用能导致未折叠蛋白积累的化学应激源，检测了哺乳动物培养细胞中CCT亚基蛋白的应激反应。在亚砷酸钠持续化学应激下，HeLa细胞中CCT亚基蛋白水平协同且短暂地上调。在从亚砷酸钠或脯氨酸类似物L-氮杂环丁烷-2-羧酸引起的化学应激中恢复期间，几种哺乳动物细胞系中的CCT亚基水平也上调。在应激恢复过程中，发现几种新合成的、与CCT相关的未鉴定蛋白会与CCT亚基自身及已知底物同时增加。这些结果表明，CCT通过协助在此期间积极合成和/或复性的蛋白进行折叠，在细胞从蛋白质损伤中恢复过程中发挥重要作用。
