RUI: Collaborative Research: Head Group Preference in Recluse Spider Phospholipase D Toxins

RUI：合作研究：隐士蜘蛛磷脂酶 D 毒素的头群偏好

• 批准号: 1807885
• 负责人: Greta Binford
• 金额: $ 12万
• 依托单位: Lewis and Clark College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1807885&HistoricalAwards=false
• 关键词: RUI; Collaborative; Research; Head; Group

With this award, the Chemistry of Life Processes Program in the Chemistry Division is supporting a collaborative project between Dr. Matthew Cordes at the University of Arizona and Dr. Greta Binford at Lewis and Clark College, to determine how spider venom toxins target and destroy different molecules on cell surfaces. Venoms of brown recluse spiders have toxins that cause the death of cells and tissue in mammals, but also help the spiders immobilize and/or digest insect prey. The toxins that are known to affect mammals can damage cell surfaces by cutting a specific "head group", called choline, off of a molecule called a sphingolipid. Other recluse spider toxins can only cut off a different kind of head group, called ethanolamine, that mammals do not have in their sphingolipids, so these toxins may be less harmful to mammals. Many insects have both kinds of head group, so both types of toxin are probably important for predation, perhaps in different ways. Dr. Cordes, a structural biologist and biochemist, and Dr. Binford, a biologist and expert on venomous invertebrates, combine their expertise to determine how these toxins distinguish the different head groups, and what the biological consequences are for predators and their prey. The specific action of these toxins on different head groups could also make them useful in biotechnology for detecting or manipulating different kinds of cell surfaces. The broader impacts of this project involve outreach through mentorship of undergraduates doing integrative and collaborative research at two different institutions. Spiders attract public interest and afford an opportunity to inform the public on scientific investigations on the subject. An innovative program known as "SpiderFest" is conduucted both at the laboratory and at a science expo in Portland. The overall goal of this project is to understand the causes and effects of substrate head group (ethanolamine vs. choline) preference in phospholipase D toxins from recluse spiders. The specific goals are to map interfacial binding sites in the toxins, elucidate amino-acid sequence determinants of substrate head group preference; characterize the evolution of substrate preference in the recluse spider toxin family; and correlate head group preference to biological effects of the toxins. Methods to be used include NMR, X-ray crystallography, computational structural biology, site-directed mutagenesis, phylogenetic reconstruction, enzymatic assays, and biological assays. Information from this study illuminates differential recognition, by proteins that act at membrane surfaces, of the two most common lipid head groups in nature, phosphocholine and phosphoethanolamine. The project also sheds light on toxin recruitment and specialization in venoms and interesting aspects of arthropod biochemistry and neurobiology. These toxins could also be developed into valuable analytical tools to probe important differences in cell surface structure.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

凭借该奖项，化学部的生命过程化学项目正在支持亚利桑那大学的 Matthew Cordes 博士和刘易斯和克拉克学院的 Greta Binford 博士之间的合作项目，以确定蜘蛛毒液毒素如何瞄准并破坏细胞表面的不同分子。 棕色隐士蜘蛛的毒液含有毒素，可导致哺乳动物细胞和组织死亡，但也有助于蜘蛛固定和/或消化昆虫猎物。 已知影响哺乳动物的毒素可以通过从鞘脂分子上切除特定的“头基”（称为胆碱）来损害细胞表面。其他隐士蜘蛛毒素只能切断一种不同的头部基团，称为乙醇胺，哺乳动物的鞘脂中没有这种物质，因此这些毒素对哺乳动物的危害可能较小。许多昆虫都有两种头群，因此这两种毒素可能对捕食都很重要，也许以不同的方式。结构生物学家和生物化学家 Cordes 博士和生物学家兼有毒无脊椎动物专家 Binford 博士结合他们的专业知识，确定这些毒素如何区分不同的头群，以及对捕食者和猎物的生物学后果。这些毒素对不同头部基团的特定作用也可能使它们在生物技术中用于检测或操纵不同类型的细胞表面。 该项目更广泛的影响包括通过指导在两个不同机构进行综合和合作研究的本科生来进行推广。 蜘蛛吸引了公众的兴趣，并提供了向公众通报有关该主题的科学研究的机会。一项名为“SpiderFest”的创新计划在实验室和波特兰的科学博览会上进行。该项目的总体目标是了解隐士蜘蛛磷脂酶 D 毒素中底物头基（乙醇胺与胆碱）偏好的原因和影响。具体目标是绘制毒素中的界面结合位点图谱，阐明底物头基偏好的氨基酸序列决定因素；表征隐士蜘蛛毒素家族底物偏好的演变；并将头组偏好与毒素的生物效应相关联。使用的方法包括核磁共振、X射线晶体学、计算结构生物学、定点诱变、系统发育重建、酶测定和生物测定。这项研究的信息阐明了作用于膜表面的蛋白质对自然界中两种最常见的脂质头基——磷酸胆碱和磷酸乙醇胺——的差异识别。该项目还揭示了毒素的招募和毒液的专门化以及节肢动物生物化学和神经生物学的有趣方面。这些毒素还可以开发成有价值的分析工具，以探测细胞表面结构的重要差异。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。