Hsp70与淀粉样蛋白相互作用的结构生物学研究

蛋白质的淀粉样纤维化聚集是淀粉样疾病的重要发病机制之一。分子伴侣有调控蛋白质淀粉样纤维化聚集的功能。Hsp70能与酵母prion蛋白Ure2和人类帕金森氏症相关蛋白α-synuclein(α-syn)直接相互作用，从而抑制它们的体内外淀粉样纤维化聚集。我们拟通过NMR等方法从结构生物学角度研究Hsp70与Ure2和α-syn的相互作用，确定Hsp70的底物结合结构域与这两个淀粉样蛋白的相互作用位点和关键残基，通过构建突变体，结合淀粉样纤维化的监测手段研究各关键残基在成纤维抑制中的作用；鉴定Hsp70的C末端结构域在相互作用中的功能；并且研究α-syn在与Hsp70结合时发生的构象变化，试图揭示Hsp70抑制α-syn成纤维的机制，从而从结构生物学角度揭示Hsp70对淀粉样蛋白纤维化聚集的调控机制。我们的研究将为淀粉样疾病的发病机制研究及防治提供重要的结构生物学线索。

Protein amyloid fibril formation is important in the pathogenesis of amyloid diseases. Chaperones can regulate amyloid fibril formation in vivo. Hsp70 can directly interact with the native state of the yeast prion protein Ure2 and with human α-synuclein, leading to inhibition of amyloid fibril formation of these two proteins. We plan to undertake structural study of the interaction between Hsp70 and Ure2/α-synuclein by methods such as NMR, to identify the interacting sites and key residues within the Hsp70 substrate binding domain and Ure2/α-synuclein, in order to identify the role of the Hsp70 C-terminal domain in the interaction, and to investigate conformational changes in α-synuclein when binding to Hsp70 and its relationship with fibril formation. These studies will give structural insight into the regulatory mechanism of Hsp70 in preventing amyloid fibril formation, and provide important structural clues for study of the pathogenesis and treatment of amyloid diseases.