Mechanism of allosteric signal integration in Src tyrosine kinase

描述(由申请人提供)：蛋白激酶作为关键的细胞途径调节因子，经常与疾病有关，并为治疗干预提供机会。由于它们的普遍存在和重要性，严格调控激酶活性对于控制细胞周期、增殖、分化、运动、细胞死亡或存活等基本细胞过程是必要的。小分子激酶抑制剂因其靶向激酶的能力而被选中 三磷酸腺苷结合袋已取得临床应用。然而，在500多个人类蛋白激酶中发现的口袋的高度序列和结构保守，给开发针对单个蛋白激酶的抑制剂带来了挑战。使用这些工具时存在许多限制 小分子抑制剂源于它们对其他与靶向疾病过程无关的激酶的交叉抑制。然而，蛋白激酶实现精确调控的部分机制涉及到许多分子间和分子内信号的整合，这些信号通过在序列和功能上相当不保守的位点进行整合。因此，这些非保守的调控机制为更精确的治疗靶向提供了机会，例如，通过开发基于高亲和力和高特异性配体的变构抑制剂。然而，要详细地确定这样的变构位点是具有挑战性的。最近，我的赞助人的实验室发现了一个以前未知的氨基酸变构网络，它跨越了激酶的长度，因此可能有助于变构信号的整合 对蛋白激酶催化结构域活性的调节。我建议从实验上探索变构网络，并确定稳定预测变构口袋的配体。这项工作的发现将加深我们对这类重要药物靶点的基本调控机制的理解，并可能为开发更具体的治疗方法开辟道路。

DESCRIPTION (provided by applicant): Protein kinases, as key cellular pathway regulators, are frequently linked to disease and provide opportunities for therapeutic intervention. Due to their prevalence and importance, strict regulation of kinase activity is necessary to control essential cellular processes including the cell cycle, proliferation, differentiation, motility, an cell death or survival. Small molecule kinase inhibitors selected for their ability to target the kinase ATP-binding pocket have achieved clinical utility. However, the high sequence and structural conservation of the pocket found in the more than 500 human protein kinases has created a challenge to developing inhibitors specific for individual kinases. Many limitations in using these small molecule inhibitors derive from their cross-inhibition of other kinases unconnected to the targeted disease process. Part of the mechanism through which protein kinases achieve precise regulation, though, involves integration of many inter- and intramolecular signals via sites that are considerably less well conserved in sequence and function. These non-conserved mechanisms of regulation therefore provide the opportunity for more precise therapeutic targeting, for example, through the development of allosteric inhibitors based on high-affinity and high-specificity ligands. However, it is challenging to identify such allosteric sites in detai. Recently, my sponsor's laboratory identified a previously unknown allosteric network of amino acids that spans the length of the kinase and may thus facilitate integration of allosteric signals into the regulation of protein kinase catalytic domain activity. I propose to experimentally probe the allosteric network and identify ligands that stabilize a predicted allosteric pocket. The findings from this work will deepen our understanding of the fundamental regulatory mechanisms for this important class of drug targets and potentially open the way to the development of more specific therapeutics.