Coordinated Activation of Hsp70 Chaperones
Coordinated Activation of Hsp70 Chaperones
复制标题
Hsp70 伴侣的协调激活
作者：
G. Steel;Donna Fullerton;J. R. Tyson;C. Stirling
Hsp70是一个普遍存在的分子伴侣家族，参与许多细胞过程。酵母内质网中蛋白质的生物合成需要两个Hsp70，Lhs1p和Kar2p。在这里，我们发现Lhs1p和Kar2p特异性地相互作用，耦合并协调调节各自的活动。Lhs1p通过提供特定的核苷酸交换活性来刺激Kar2p，而Kar2p则相互激活Lhs1p三磷酸腺苷酶(ATPase)。这两种ATPase活性是偶联的，它们的协调调节对于体内的正常功能是必不可少的。
Hsp70s are a ubiquitous family of molecular chaperones involved in many cellular processes. Two Hsp70s, Lhs1p and Kar2p, are required for protein biogenesis in the yeast endoplasmic reticulum. Here, we found that Lhs1p and Kar2p specifically interacted to couple, and coordinately regulate, their respective activities. Lhs1p stimulated Kar2p by providinga specific nucleotide exchange activity, whereas Kar2p reciprocally activated the Lhs1p adenosine triphosphatase (ATPase). The two ATPase activities are coupled, and their coordinated regulation is essential for normal function in vivo.