Zhao Rongmin, Houry Walid A
Walid A. Houry-Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
Adv Exp Med Biol. 2007;594:27-36. doi: 10.1007/978-0-387-39975-1_3.
Hsp90 is an essential and ubiquitous molecular chaperone that is required for the proper folding of a set of client proteins at a late stage in their folding process. In eukaryotes, cytoplasmic Hsp90 is absolutely essential for cell viability under all growth conditions. The functional cycle of the Hsp90 system requires a cohort of cochaperones and cofactors that regulate the activity of this chaperone. Hence, Hsp90 function is highly complex; in order to understand that complexity, several groups have attempted to map out the interaction network of this chaperone in yeast and mammalian systems using the latest available proteomic and genomic tools. Interaction networks emerging from these large scale efforts clearly demonstrate that Hsp90 plays a central role effecting multiple pathways and cellular processes. In yeast Saccharomyces cerevisiae, Hsp90 was shown to interact directly or indirectly with at least 10% of the yeast ORFs. The systematic application of large scale approaches to map out the Hsp90 chaperone network should allow the determination of the mechanisms employed by this chaperone system to maintain protein homeostasis in the cell.
热休克蛋白90（Hsp90）是一种必不可少且普遍存在的分子伴侣，它在一组客户蛋白折叠过程的后期阶段，对其正确折叠是必需的。在真核生物中，细胞质Hsp90在所有生长条件下对细胞活力绝对至关重要。Hsp90系统的功能循环需要一群辅助伴侣蛋白和辅助因子来调节这种伴侣蛋白的活性。因此，Hsp90的功能高度复杂；为了理解这种复杂性，几个研究小组试图利用现有的最新蛋白质组学和基因组学工具，在酵母和哺乳动物系统中绘制出这种伴侣蛋白的相互作用网络。这些大规模研究得出的相互作用网络清楚地表明，Hsp90在影响多种途径和细胞过程中起着核心作用。在酿酒酵母中，已表明Hsp90与至少10%的酵母开放阅读框直接或间接相互作用。系统应用大规模方法来绘制Hsp90伴侣蛋白网络，应该能够确定该伴侣蛋白系统在细胞中维持蛋白质稳态所采用的机制。
