Small Molecule Modulators of the Actin Cytoskeleton

描述（由申请人提供）：细胞中的肌动蛋白丝动力学是多种过程的基础，例如神经元轴突导向、吞噬作用、血小板活化、细胞器运动、细胞运动和癌症转移。在分子水平上理解肌动蛋白动力学将使我们深入了解这些过程，并可能导致识别新的药物靶点，用于抑制肿瘤细胞的侵袭和转移。特别是小分子在探测细胞骨架动力学等快速过程中发挥了重要作用，尽管其中大部分都是偶然发现的。该研究项目的中心是系统地发现小分子工具，以研究哺乳动物细胞中的肌动蛋白动力学。提出了五个目标：1）鉴定G72* 的分子靶点，G72 * 是抑制爪蟾卵提取物中磷酸肌醇（4，5）二磷酸（PIP 2）诱导的肌动蛋白组装的环肽。2)使用多样性导向的合成方法生成细胞可渗透的环状和近端封端肽的文库。3)纯化海绵提取物，并将所得半纯级分用于高通量筛选。4)筛选合成和天然产物库中抑制佛波醇-12-肉豆蔻酸酯-13-乙酸酯（PMA）诱导的哺乳动物细胞膜皱褶的化合物。5)结合亲和层析和蛋白质组学分析方法，鉴定在膜皱褶过程中与F-肌动蛋白特异性结合的磷蛋白和蛋白质。

DESCRIPTION (provided by applicant): Actin filament dynamics in the cell underlie diverse processes, such as neuronal axon guidance, phagocytosis, platelet activation, organelle movement, cell motility, and cancer metastasis. Understanding actin dynamics at the molecular level will give us insight into these processes and may lead to the identification of new drug targets for the inhibition of tumor cell invasion and metastasis. Small molecules in particular have been instrumental in probing fast process such as cytoskeletal dynamics, although most of these have been discovered by serendipity. This research program centers on the systematic discovery of small molecule tools with which to study actin dynamics in mammalian cells. Five aims are proposed: 1) To identify the molecular target of G72*, a cyclic peptide that inhibits phosphoinositol(4,5) bisphosphate (PIP2)-induced actin assembly in Xenopus egg extracts. 2) To generate libraries of cell-permeable cyclic and near, end-capped peptides using diversity-oriented synthetic methods. 3) To purify marine sponge extracts and format the resulting semi-pure fractions for high-throughput screening. 4) To screen synthetic and natural product libraries for compounds that inhibit phorbol-12-myristate-13-acetate (PMA)-induced membrane ruffling in mammalian cells. 5) To identify phosphoproteins and proteins that associate specifically with F-actin assembled during membrane ruffling using a combination of affinity chromatography and proteomic profiling methods.