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通路调节剂，通常与疾病相关，并为治疗干预提供机会。由于它们的普遍性和重要性，激酶活性的严格调节对于控制基本细胞过程（包括细胞周期、增殖、分化、运动性、细胞死亡或存活）是必要的。小分子激酶抑制剂因其靶向激酶的能力而被选择 ATP结合口袋已实现临床应用。然而，在超过500种人类蛋白激酶中发现的口袋的高度序列和结构保守性对开发针对单个激酶的特异性抑制剂产生了挑战。使用这些工具的许多限制 小分子抑制剂来源于它们对与靶向疾病过程无关的其它激酶的交叉抑制。然而，蛋白激酶实现精确调节的部分机制涉及许多分子间和分子内信号通过序列和功能保守性相当低的位点的整合。因此，这些非保守的调节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，详细鉴定这种变构位点是具有挑战性的。最近，我的赞助人的实验室确定了一个以前未知的氨基酸变构网络，跨越激酶的长度，因此可能有助于整合变构信号 蛋白激酶催化域活性的调节。我建议实验探测变构网络，并确定稳定预测的变构口袋的配体。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.