Chemical Probes That Modulate Phosphatidylinositol-5-Phosphate 4-Kinase Activity

描述(申请人提供)：这项建议旨在确定和优化人PI5P4K的特定调节剂，磷脂酰肌醇-5-磷酸4-激酶(类型II PIPK)，这是一种调节AKT信号和肿瘤细胞生长的激酶家族。将追求以下具体目标：(1)使用针对含有约40万个小分子的MLSMR的定量高通量筛选方法来鉴定人PI5P4K的抑制剂。(2)在一系列二级检测中验证已鉴定化合物的效力，其中包括选择性分析，以鉴定那些不影响PI4P5K、磷脂酰肌醇-4-磷酸5-激酶(I型PIPK)和PI3P5K(磷脂酰肌醇-3-磷酸5-激酶(类型III PIPK/FAB1/PIKfyve))的化合物。我们将以PI5P4K基因敲除的小鼠胚胎成纤维细胞(MEF)和基因敲除细胞为对照，测试这些PI5P4K探针对细胞PI5P积聚和细胞增殖的影响和特异性。(3)除了这项建议的授予期限外，检查最有效的PI5P4K探针在小鼠癌症模型中减少肿瘤生长的能力。

DESCRIPTION (provided by applicant): This proposal aims to identify and optimize specific modulators of human PI5P4K, phosphatidylinositol- 5-phosphate 4-kinase (Type II PIPK), a family of kinases that regulate AKT signaling and tumor cell growth. The following specific aims will be pursued: (1) to identify inhibitors of human PI5P4K using a quantitative high-throughput screening approach against the MLSMR containing ~400,000 small molecules. (2) To validate the potency of the identified compounds in a panel of secondary assays, which consist of selectivity assays to identify those compounds that do not affect PI4P5K, phosphatidylinositol- 4-phosphate 5-kinase (Type I PIPK), and PI3P5K, the phosphatidylinositol-3-phosphate 5-kinase (Type III PIPK /Fab1/PIKfyve). We will test the impact and specificity of these PI5P4K probes on cellular PI5P accumulation and cell proliferation using PI5P4K knockout mouse embryonic fibroblasts (MEFs) and knockdown cells as controls. (3) Beyond the granting term for this proposal, to examine the most potent PI5P4K probes for their ability to decrease tumor growth in mouse models of cancer.