Small Molecule Tools to Image and Understand Sophisticated Protein Function

 描述（由申请人提供）：在上一个供资周期，我们开发并应用了一种称为“二分Cys 4显示”的化学生物学工具。二分半胱氨酸4显示提供了完整的蛋白质，核磁共振和晶体学不能和结构动力学是可见的条件下的结构信息。它作用于细胞和靶点，如受体酪氨酸激酶，其动态结构与功能密切相关。有了这个工具， 对一种受体酪氨酸激酶（表皮生长因子受体（EGFR））（一种非常重要的癌症靶点）如何跨细胞膜传递化学信息的重要见解。这些见解导致分子-细胞穿透，碳氢化合物钉肽-抑制EGFR，在细胞中，以一种新的方式，通过变构。我们还意外地发现了新的变构EGFR激活剂。我们了解到生长因子与细胞表面的EGFR结合诱导细胞质内膜段（JM）中生长因子依赖性卷曲螺旋，其与激酶活化有关。在这次更新中，我们首先应用最先进的 结构和计算方法，以提高活性和耐药性（L 858 R/T790 M）EGFR的效力和选择性，并阐明EGFR活化剂用于伤口愈合应用的机制。我们建立在我们的发现，WT，活化，和L 858 R/T790 M EGFR（DM EGFR）的不同，在以前未被认识的方式-他们的JM段含有不同的卷曲螺旋。这种差异提供了一种选择性抑制DM EGFR的分子的途径，单独或与小分子酪氨酸激酶抑制剂协同。接下来，我们询问EGFR如何将JM结构解码为配体依赖性生物学，最后将我们的焦点扩大到包括目前在乳腺癌中非常感兴趣的异二聚体ErbB 2/3。这项工作将提供最难以捉摸的所有蛋白质功能之一-变构-在最重要的人类癌基因家族之一-EGFR的背景下的基本信息。我们将学习变构如何编码ErbB蛋白中的化学和突变信息，这些信息如何传递到生物功能中，以及变构转换的知识如何指导具有新颖和所需活性的强效，选择性抑制剂（或抑制剂组合）的设计。

 DESCRIPTION (provided by applicant): In the previous funding cycle, we developed and applied a chemical biology tool called `bipartite Cys4 display'. Bipartite Cys4 display provides structural information about intact proteins that NMR and crystallography cannot and under conditions where structural dynamics are visible. It operates in cells and on targets, like recepto tyrosine kinases, whose dynamic structure is tied intimately to function. With this tool, we gained critical insights into how one receptor tyrosine kinase, the epidermal growth factor receptor (EGFR), an exceptionally important cancer target, communicates chemical information across the plasma membrane. These insights led to molecules-cell penetrating, hydrocarbon-stapled peptides-that inhibit EGFR, in cells, in a new way, via allostery. We also serendipitously discovered novel, allosteric EGFR activators. We learned that growth factor binding to EGFR on the cell surface induces growth factor-dependent coiled coils in the cytoplasmic juxtamembrane segment (JM) that are linked to kinase activation. In this renewal, we first apply state-of-the art structural and computational methods to improve potency and selectivity for activated and drug-resistant (L858R/T790M) EGFR and elucidate the mechanism of EGFR activators for wound healing applications. We build on our discovery that WT, activated, and L858R/T790M EGFR (DM EGFR) differ in a previously unrecognized way- their JM segments contain different coiled coils. This difference provides a path towards molecules that selectively inhibit DM EGFR, alone or synergistically in combination with small molecule tyrosine kinase inhibitors. Next, we interrogate how EGFR decodes JM structure into ligand-dependent biology, and finally broaden our focus to include the heterodimeric ErbB2/3, of great current interest in breast cancer. This work will provide fundamental information on one of the most elusive of all protein functions-allostery-in the context of one of most important human oncogene family-EGFR. We will learn how allostery encodes chemical and mutational information in ErbB proteins, how this information is transmitted into biologic function, and how knowledge of allosteric transitions can guide the design of potent, selective inhibitors (or inhibitor combinations) with novel and needed activities.