Chemical Agents That Affect Biomembrane Function

影响生物膜功能的化学试剂

• 批准号: 6606706
• 负责人: BRADLEY D. SMITH
• 金额: $ 26.47万
• 依托单位: UNIVERSITY OF NOTRE DAME
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6606706
• 关键词: analytical method; apoptosis; biomarker; chemical conjugate; chemical synthesis; conformation; drug delivery systems; membrane activity; membrane fusion; membrane structure; membrane transport proteins; method development; molecular polarity; peptide library; phosphatidylserines; phospholipids; prodrugs; prostate neoplasms; protein binding; spectrometry; synthetic enzyme

DESCRIPTION (provided by applicant): The broad, long-term objectives are to synthesize and evaluate organic molecules that can affect dynamic membrane processes such as fusion, phospholipid flip-flop, pore formation and cell surface recognition. The research is conducted for two major reasons: (a) The studies provide useful insight into the supramolecular factors that control these biomedically important processes; (b) Organic compounds are produced that can be used as reagents in membrane biology research, diagnostic indicators of disease, or as pharmaceutical leads. The specific aims of this proposal are, 1: Develop a synthetic sensor for phosphatidylserine (PS) appearance on the surface of a cell which is a hallmark of cell apoptosis. Currently, dye-labeled Annexin V is used extensively as a PS-sensing reagent that detects apoptosis, but this protein-based detection method has a number of limitations. Parallel synthesis and screening methods will be used to prepare and identify a synthetic PS-sensor that can provide a quantitative measure of apoptotic index for heterogeneous samples such as blood, spleen, lymph nodes and bone marrow. This PS-sensor could then be used to develop a clinically useful method of measuring the efficacy of anticancer drugs in individual patients. 2: Develop a synthetic PS-scramblase as a new way to help the body eliminate pathogenic cells. Parallel synthesis and screening methods will be used to identify an organic compound that can scramble the distribution of PS across plasma membranes. It is hypothesized that an increase in the concentration of externalized PS will trigger cell clearance by phagocytosis. 3: A novel prodrug strategy will selectively deliver the apoptosisinducing compound described in aim 2 to prostate cancer cells. The prodrug is activated by the prostate specific membrane antigen (PSMA) that is present in elevated amounts on the surface of prostate tumor cells. 4: Test the hypothesis that phospholipids can adopt an extended conformation (the non-polar tails extend in opposite directions) during important dynamic membrane processes such as fusion, phospholipid flip-flop, pore formation and binding of peripheral proteins. The experimental approach is to compare the supramolecular properties of conformationally restricted polar lipids that are unable to adopt a fully extended conformation with more flexible analogues that can. If the extended conformation hypothesis is confirmed then it represents a new and very different view of phospholipid dynamics.

描述（由申请人提供）：广泛的长期目标是合成和评价可影响动态膜过程（如融合、磷脂翻转、孔形成和细胞表面识别）的有机分子。进行这项研究有两个主要原因：（a）这些研究为控制这些生物医学重要过程的超分子因素提供了有用的见解;（B）产生的有机化合物可用作膜生物学研究中的试剂，疾病的诊断指标或药物先导。该提案的具体目标是，1：开发一种用于细胞表面上磷脂酰丝氨酸（PS）外观的合成传感器，其是细胞凋亡的标志。目前，染料标记的膜联蛋白V被广泛用作检测细胞凋亡的PS传感试剂，但这种基于蛋白质的检测方法具有许多局限性。平行合成和筛选方法将用于制备和鉴定合成PS传感器，其可以提供异质样品如血液、脾、淋巴结和骨髓的凋亡指数的定量测量。这种PS传感器可用于开发一种临床上有用的方法，用于测量抗癌药物在个体患者中的疗效。2：开发一种合成的PS-scramblase作为帮助身体消除致病细胞的新方法。平行的合成和筛选方法将被用来确定一种有机化合物，可以扰乱PS跨质膜的分布。假设外化PS浓度的增加将通过吞噬作用触发细胞清除。3：一种新的前药策略将选择性地将目标2中所述的前列腺癌诱导化合物递送至前列腺癌细胞。前药由前列腺特异性膜抗原（PSMA）激活，PSMA以升高的量存在于前列腺肿瘤细胞表面。第四章：检验磷脂在重要的动态膜过程中（如融合、磷脂翻转、孔形成和外周蛋白结合）可以采用延伸构象（非极性尾部向相反方向延伸）的假设。实验方法是比较超分子性质的构象限制的极性脂质，无法采用一个完全扩展的构象与更灵活的类似物，可以。如果扩展构象假说得到证实，那么它代表了磷脂动力学的一个新的和非常不同的观点。