BIOCHEMICAL MECHANISM OF AMYLOID DISEASE

这项研究的长期目标是了解生物化学 淀粉样蛋白病的发病机制 淀粉样原纤维形成是指 一种正常可溶的蛋白质不正常地自组装成一种不可溶的蛋白质 交叉β-折叠四级结构形式，是 淀粉样疾病 了解正常可溶性蛋白质是如何 转化成淀粉样纤维是理解 这种疾病的发病机制，是本提案的重点。 蛋白质 甲状腺素运载蛋白构成两种不同类型的淀粉样纤维 人类淀粉样蛋白病 甲状腺素运载蛋白淀粉样纤维的形成机制 将使用体外系统研究形成，该系统模拟低浓度的 认为淀粉样纤维形成的细胞器的pH环境 在体内发生。 这种体外系统的优点是其 简单，这将使我们能够进行仔细的测量。 酸介导的甲状腺素运载蛋白部分变性足以 体外淀粉样纤维形成。 一种结构化的酸性形式， 甲状腺素运载蛋白似乎是淀粉样蛋白的前体 纤维 甲状腺素运载蛋白变性和淀粉样纤维形成是 竞争过程，现在可以单独研究，由于 发现了一种抑制剂，其防止淀粉样蛋白原纤维形成， 明显干扰变性途径。 因此在 淀粉样蛋白抑制剂的存在下，可以研究甲状腺素运载蛋白变性 在没有抑制剂的情况下，可以研究原纤维的形成。 是 我们的首要任务是确定甲状腺素运载蛋白变性的性质， 能够形成原纤维的中间体。 变性途径和 还将检查甲状腺素运载蛋白变体形成原纤维的能力 in the course课程of these studies研究. 基于结构的淀粉样蛋白抑制剂 将测试它们抑制淀粉样纤维的能力， 阵 成功的抑制剂与动力学和 热力学变性和原纤维形成的研究应该允许 原纤维形成的机制有待制定。 某些酸诱导构象的长期结构研究 将在这些研究期间启动甲状腺素运载蛋白， 目的是表征变性中间体， 淀粉样纤维的前体

The long term goal of this research is to understand the biochemical mechanism of amyloid disease. Amyloid fibril formation refers to the abnormal self-assembly of a normally soluble protein into an insoluble cross beta-sheet quaternary structural form and is the causative agent in amyloid disease. Understanding how a normally soluble protein is transformed into amyloid fibrils is a critical part of understanding the mechanism of this disease and is the focus of this proposal. The protein transthyretin composes the amyloid fibrils in two different types of human amyloid disease. The mechanism of transthyretin amyloid fibril formation will be studied using an in vitro system that simulates the low pH environment of the organelle where amyloid fibril formation is thought to occur in vivo. The advantage of this in vitro system is its simplicity, which will enable us to make careful measurements. The acid-mediated partial denaturation of transthyretin is sufficient for amyloid fibril formation in vitro. A structured acidic-form of transthyretin appears to be the precursor that assembles into amyloid fibrils. Transthyretin denaturation and amyloid fibril formation are competitive processes that can now be studied individually due to the discovery of an inhibitor which prevents amyloid fibril formation without noticeably interfering with the denaturation pathway. Thus, in the presence of amyloid inhibitor, transthyretin denaturation can be studied and in the absence of inhibitor, fibril formation can be studied. It is our priority to identify the nature of the transthyretin denaturation intermediate competent to form fibrils. The denaturation pathway and the ability of transthyretin variants to form fibrils will also be examined in the course of these studies. Structurally based amyloid inhibitors will be tested with regard to their ability to curb amyloid fibril formation. Successful inhibitors in combination with kinetic and thermodynamic denaturation and fibril formation studies should allow a mechanism of fibril formation to be formulated. Long term structural studies on certain acid induced conformations of transthyretin will be initiated during these studies with the ultimate goal of characterizing the denaturation intermediate that is the precursor to amyloid fibrils.