Development of an ICMT Supported Membrane Sensor

该项目的长期目标是开发基于多元素膜的传感器阵列， 用于高通量、并行感测作用于特定靶点的治疗剂候选物的单芯片 膜蛋白靶点。这种传感技术的成功开发可以加速药物 发现靶向膜蛋白参与多种疾病。我们将建立一个稳定的 不对称膜结构，其中含有异戊二烯基半胱氨酸羧甲基转移酶（ICMT）， 项目作为癌症化疗药物发现的潜在新工具。ICMT是一种膜蛋白， 内质网负责-CaaX基序蛋白的羧基甲基化，包括Ras 信号转导蛋白这种膜传感器结构将使得能够检测Icmt介导的 图10示出了模型底物N-乙酰法尼基半胱氨酸的甲基化作为由于N-乙酰法尼基半胱氨酸的甲基化引起的荧光发射的变化。 二硫键连接的分子信标的偶联裂解。传感器从这些不对称的 结构将提供候选药物抑制由Icmt催化的甲基化的能力的直接指示。 这种方法将作为一种强大的工具，用于筛选药物库中的先导化合物， 抑制细胞致癌Ras蛋白的甲基化。这些化合物的发现和开发 是重要的，因为Ras羧基甲基化的抑制不仅促进Ras的错误定位， 蛋白质，但也抑制Ras转化细胞的能力。ICMT是一个优秀的模型系统， 这种基于膜的传感器的发展，因为存在许多良好表征的基底， 数据验证这些底物将被用作开发高通量筛选方法的工具 这可能导致改进的化疗药物用于难治性肿瘤。项目的后续阶段 将解决设计，制造，表征，和多元素传感器阵列上的验证， 光学透明衬底。将采用多学科团队方法，结合以下方面的专业知识： 生物化学，材料合成和表征，分析化学和理论，以实现目标 支撑膜装置这种探测器阵列概念的未来扩展可能具有深远的意义 加速发现靶向许多其他类别的新治疗剂的潜力 膜相关蛋白。

The long term goal of this project is the development of multi-element membrane-based sensor arrays on a single chip for high-throughput, parallel sensing of therapeutic agent candidates acting on specific membrane protein targets. Successful development of this sensing technology can lead to accelerated drug discovery targeted to membrane proteins involved in a variety of diseases. We will develop a stabilized asymmetric membrane structure containing isoprenylcysteine carboxylmethyltransferase (ICMT) in this project as a potential new tool for drug discovery in cancer chemotherapy. ICMT is a membrane protein in the endoplasmic reticulum responsible for the carboxylmethylation of -CaaX motif proteins, including the Ras signal transduction proteins. This membrane sensor architecture will enable the detection of Icmt-mediated methylation of the model substrate N-acetylfarnesylcysteine as a change in fluorescence emission due to the coupled cleavage of a disulfide-linked molecular beacon. Sensors developed from these asymmetric structures will provide a direct indication of a drug candidate's ability to inhibit methylation catalyzed by Icmt. This approach will serve as a powerful tool for screening drug libraries for lead compounds that are likely to inhibit the methylation of cellular oncogenic Ras proteins. Discovery and development of these compounds are important because inhibition of Ras carboxylmethylation promotes not only the mislocalization of the Ras proteins, but also inhibits the ability of Ras to transform cells. ICMT is an excellent model system for development of this membrane-based sensor because many well-characterized substrates exist to provide data validation. These substrates will be used as tools to develop a high-throughput screening approach that may lead to improved chemotherapeutic agents for refractory tumors. Subsequent phases of the project will address the design, fabrication, characterization, and validation of multi-element sensor arrays on an optically transparent substrate. A multidisciplinary team approach will be used, combining expertise in biochemistry, materials synthesis and characterization, analytical chemistry, and theory to achieve the target supported membrane device. Future extension of this detector array concept could have far reaching potential for accelerating the discovery of new therapeutic agents targeted to many other classes of membrane-associated proteins.