Understanding Signaling by Non-Canonical Receptor Tyrosine Kinases

了解非典型受体酪氨酸激酶的信号传导

• 批准号: 9275679
• 负责人: Mark A Lemmon
• 金额: $ 80.4万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-05-01 至 2022-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9275679
• 关键词: Acylation; Binding; Binding Proteins; Biochemical; Biology; Bone Diseases; Characteristics; Chemicals; Complex; Congenital Abnormality; Defect; Diabetes Mellitus; Dimerization; Disease; Family; Goals; Growth Factor; Human; Knowledge; Ligands; Malignant Neoplasms; Methods; Molecular Conformation; Mutate; Neurodevelopmental Disorder; Phosphotransferases; Play; Receptor Activation; Receptor Protein-Tyrosine Kinases; Receptor Signaling; Recruitment Activity; Research; Research Project Summaries; Resolution; Role; Signal Transduction; Signaling Molecule; Specificity; Testing; Therapeutic; Tyrosine; WNT Signaling Pathway; Wnt proteins; Wound Healing; dimer; human disease; in vivo; insight; member; novel therapeutic intervention; novel therapeutics; receptor; receptor binding; therapeutic target

Project Summary The research proposed in this MIRA application seeks to understand unexplored mechanisms of transmembrane signaling across the receptor tyrosine kinase (RTK) superfamily, members of which play an important role in human disease – from neurodevelopmental disorders, to bone diseases, cancers, diabetes, and several congenital malformations. In the traditional view of RTK signaling, growth factor ligands induce receptor dimers that become tyrosine autophosphorylated and recruit downstream signaling molecules. As we understand more about the 20 different RTK families (which include 58 RTKs), however, it becomes clearer that this view only applies to a subset of these receptors. The research proposed here focuses on two characteristics that demand a very different mechanistic view – RTKs that bind Wnt proteins (and do not dimerize as a result) and RTKs that have `dead' kinase or pseudokinases in their intracellular regions. New paradigms must be understood in order to appreciate how these important receptors signal. Our goals over the next 5-10 years are: 1. To develop a coherent picture of the role played by RTKs in Wnt signaling (which involves 4 of the 20 RTK families), 2. To understand how RTKs with pseudokinase domains that do not even bind ATP (found in 5 of the 20 RTK families) can signal, and 3. To determine why pseudokinases are over- represented among the Wnt-regulated RTKs. Guided by cellular and in vivo studies of receptor/ligand relationships we will study ligand-induced complexes biochemically, and with high-resolution structural approaches, in order to understand in detail how Wnt protein binding leads to activation of the receptors and co-receptors in the signaling complex. In pursuing these studies, we will investigate the role played by Wnt acylation – requirements for which appear to be different for binding to Frizzled-family and RTK-family Wnt receptors. We also hope to define specificity determinants in the Wnt proteins for distinct modes of signaling. In parallel with these pursuits, we will use a structurally-guided approach, combined with chemical biology and functional analysis of mutated receptors, to explore the mechanism of signaling by pseudokinases in the RTK superfamily. These studies will have important implications for the 10% of the human kinome thought to be pseudokinases, and will systematically test the hypothesis that regulated switching of pseudokinase conformation is required for signaling. Our approaches will also bring new opportunities for therapeutic targeting of pseudokinases such as PTK7, Ror2, and Ror1, which have been implicated in several diseases. Together, our studies will provide important fundamental new insight into signaling by a class of receptors that do not fit into normal paradigms for RTKs or Wnt receptors. Understanding them is crucial for deconvoluting the complexity of Wnt signaling specificity and teasing out its multiple roles. In addition, our findings should open new avenues for potential therapeutic inhibition – as the roles of these Wnt-binding RTKs in disease become increasingly clear.

项目概要 MIRA 应用中提出的研究旨在了解未探索的机制 受体酪氨酸激酶 (RTK) 超家族的跨膜信号传导，该家族的成员发挥着重要作用 在人类疾病中发挥重要作用——从神经发育障碍到骨骼疾病、癌症、糖尿病、 以及多种先天性畸形。在 RTK 信号传导的传统观点中，生长因子配体诱导 受体二聚体发生酪氨酸自磷酸化并招募下游信号分子。正如我们 了解更多关于 20 个不同 RTK 系列（其中包括 58 个 RTK）的信息，但是，它变得更加清晰 该观点仅适用于这些受体的一部分。这里提出的研究主要集中在两个方面 需要非常不同的机制观点的特征——结合 Wnt 蛋白（并且不结合）的 RTK 结果二聚化）和在其细胞内区域具有“死”激酶或假激酶的 RTK。新的 必须理解范式才能理解这些重要受体如何发出信号。我们的目标已经结束 未来 5-10 年的目标是： 1. 对 RTK 在 Wnt 信号传导中所发挥的作用形成一个连贯的图景（其中 涉及 20 个 RTK 家族中的 4 个），2. 了解具有假激酶结构域的 RTK 如何 结合 ATP（在 20 个 RTK 家族中的 5 个家族中发现）可以发出信号，并且 3. 确定为什么假激酶过度 代表 Wnt 监管的 RTK。以受体/配体的细胞和体内研究为指导 我们将通过生物化学和高分辨率结构研究配体诱导的复合物的关系 方法，以便详细了解 Wnt 蛋白结合如何导致受体激活和 信号复合体中的共受体。在进行这些研究时，我们将调查 Wnt 所扮演的角色 酰化——结合卷曲家族和 RTK 家族 Wnt 的要求似乎不同 受体。我们还希望定义 Wnt 蛋白中不同信号传导模式的特异性决定因素。 在这些追求的同时，我们将使用结构引导的方法，结合化学生物学和 突变受体的功能分析，探索 RTK 中假激酶的信号传导机制 超家族。这些研究将对 10% 的人类激酶组产生重要影响。 假激酶，并将系统地检验调节假激酶转换的假设 信号传递需要构象。我们的方法也将为治疗带来新的机会 靶向 PTK7、Ror2 和 Ror1 等假激酶，这些酶与多种疾病有关。 总之，我们的研究将为一类受体的信号传导提供重要的基本新见解， 不符合 RTK 或 Wnt 受体的正常范式。理解它们对于反卷积至关重要 Wnt 信号传导特异性的复杂性并梳理出其多重作用。此外，我们的研究结果应该 为潜在的治疗抑制开辟新途径——这些 Wnt 结合 RTK 在疾病中的作用 变得越来越清晰。