期刊
EUROPEAN JOURNAL OF BIOCHEMISTRY
卷 268, 期 24, 页码 6335-6345出版社
WILEY
DOI: 10.1046/j.0014-2956.2001.02580.x
关键词
ATP; small heat shock protein; alpha-crystallin; alpha B-crystallin; molecular chaperone
Small heat-shock proteins (sHSPs) are a ubiquitous family of low molecular mass (15-30 kDa) stress proteins that have been found in all organisms. Under stress, sHSPs such as alpha -crystallin can act as chaperones binding partially denatured proteins and preventing further denaturation and aggregation. Recently, it has been proposed that the function of sHSPs is to stabilize stress-denatured protein and then act cooperatively with other HSPs to renature the partially denatured protein in an ATP-dependent manner. However, the process by which this occurs is obscure. As no significant phosphorylation of alpha -crystallin was observed during the renaturation, the role of ATP is not clear. It is now shown that ATP at normal physiological concentrations causes sHSPs to change their confirmation and release denatured protein, allowing other molecular chaperones such as HSP70 to renature the protein and renew its biological activity. In the absence of ATP, sHSPs such as alpha -crystallin are more efficient than HSP70 in preventing stress-induced protein aggregation. This work also indicates that in mammalian systems at normal cellular ATP concentrations, sHSPs are not effective chaperones.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据