Structural basis of amyloid fibril recognition by a conformation-sensitive antibody domain

许多不同的蛋白质序列可以错误折叠成与疾病相关的淀粉样蛋白原纤维，这些淀粉样蛋白原纤维具有共同的但尚未完全了解的结构。淀粉样蛋白研究中一个很有前途的工具是产生抗体，通过它们的特定构象来识别淀粉样蛋白原纤维。Fandrich实验室之前已经获得了一种重组抗体结构域，称为B10，它以一种构象依赖的方式与不同的淀粉样蛋白原纤维结合，例如来自阿尔茨海默氏a β肽或血清淀粉样蛋白a的原纤维。此外，B10通过稳定Aβ原纤维（成熟淀粉样原纤维的结构前体）来阻止成熟原纤维的形成。我在此建议评估B10能够结合不同淀粉样蛋白原纤维的共同表位的分子基础。这项工作将包括详细评估不同结构的Aβ聚集体和来自不同多肽序列的淀粉样原纤维的B10特异性，B10互补区域的定点诱变，x射线晶体学和其他生化方法。这些研究旨在提供有关构象敏感抗体结合和淀粉样原纤维分子结构的信息。这些数据对于构象敏感抗体在基础研究、医学诊断或治疗中的进一步应用具有重要意义。

Many different protein sequences can misfold into disease-associated amyloid fibrils that share a common but not fully understood structure. A promising tool in amyloid research is the generation of antibodies that recognize amyloid fibrils by their specific conformation. The Fandrich lab has previously obtained a recombinant antibody domain, termed B10, which binds in a conformation-dependent manner to different amyloid fibrils, such as fibrils derived from Alzheimer’s Aβ peptide or serum amyloid A protein. Furthermore, B10 prevents mature fibril formation by stabilizing Aβ protofibrils, the structural precursors of mature amyloid fibrils. I here propose to assess the molecular basis by which B10 is able to bind to a common epitope of different amyloid fibrils. The work will involve in-detail assessment of the B10 specificity with differently structured Aβ aggregates and amyloid fibrils from different polypeptide sequences, site-directed mutagenesis of complementarity determining regions of B10, X-ray crystallography and other biochemical methods. These studies aim to provide information about the binding of conformation-sensitive antibodies and the molecular structure of amyloid fibrils. Such data is relevant for further applications of conformation-sensitive antibodies in basic research, medical diagnosis or therapy.