中文摘要：

分子伴侣是一类能够识别非天然蛋白并能协助其正确折叠、组装和转运的功能蛋白。最新研究发现，在原核或真核细胞中，不同结构、不同种类的分子伴侣形成了一个复杂的折叠系统，通过这个系统，蛋白质完成了从初步合成到形成具有生物活性的三维构象的过程．避免了折叠过程中多肽链的错误折叠、蛋白沉淀和有害物质的产生。文章综述了蛋白质折叠过程中不同种类分子伴侣组件的结构、功能和作用机制的研究进展，这些分子伴侣包括Hsp70、核糖体结合因子、伴侣素、前折叠素与Hsp90，并阐述了它们在蛋白质内稳态中的作用。

英文摘要：

Molecular chaperones are a kind of functional proteins which can identify the structure of non-native proteins, and assist them in correct folding, assembling and transportation. Recent studies have discovered that molecular chaperones of different structures and classes form a complex network which could handle polypeptides from the initial synthesis on ribosomes to the final stages of folding. The chaperones can recognize and bind to nascent polypeptide chains and partially folded intermediates of proteins, thus preventing aberrant folding, aggregation and toxic species in the crowded environment of the cell. The authors reviewed the advances in understanding of the structure, function and mechanism of molecular chaperones, including Hsp70, r/bosome-bound factors, chaperonins, prefoldin and Hspg0, in the pathways of protein folding. Besides, different functions of molecular chaperones in maintenance of protein homeostasis were also summarized.