Structure and Functions of small heat shock proteins

应激反应刺激细胞防御机制的启动，包括热休克蛋白（Hsps）基因的大量上调。小热休克蛋白（sHsps）是一种分子伴侣，它被动地结合底物，形成错误折叠蛋白的储存库，最终被atp依赖性伴侣蛋白重新折叠或被蛋白酶体降解。它们对底物的亲和力受到细胞条件的严格调节。最近的研究表明，sHsps还可以发挥其他生理作用，如在不同水平上调节细胞凋亡，但sHsps发挥这些功能的机制仍存在争议。

The stress response stimulates the onset of the cell-defence machinery including the massive up-regulation of heat shock protein (Hsps) genes. Small Hsps (sHsps) are molecular chaperones that passively bind their substrate to form reservoirs of misfolded proteins that will ultimately be refolded by ATP-dependent chaperones or degraded by the proteasome. Their affinity for substrates is tightly regulated by cellular conditions. Recent studies have shown that sHsps can also play other physiological roles such as regulating apoptosis at various levels, but the mechanisms by which sHsps perform these functions are still debated.