Leveraging Ion Mobility and High Resolution Mass Spectrometry to Probe Neuropeptide Modifications in Environmental Stress

在化学系化学测量与成像项目的支持下，威斯康星大学麦迪逊分校的李凌君教授和她的团队正在开发新的分析测量工具，以探测环境诱导的神经肽变化。具体来说，Li团队寻求利用最先进的分析方法（质谱和离子迁移谱），使用化学“标签”来提高表征和定量信号肽及其对铜毒性和细胞缺氧（缺氧）应激反应的修饰的敏感性和通量。预期正在开发的技术可用于研究其他生物系统。从提出的研究中获得的分子见解有可能增强对涉及神经元肽信号的正常和功能失调生物学的理解。本项目为有志于从事化学测量与神经科学交叉领域工作的学生提供了良好的培训机会。李博士还致力于通过与高中实习项目的合作和推广来提高对这些研究活动的认识和参与，这些项目有助于在早期阶段激发学生对STEM领域的兴趣。Li小组寻求开发一种创新的分析平台，将微分离与离子迁移质谱（imms）和高分辨率质谱结合起来，探测涉及铜毒性、缺氧和高碳酸血症的神经肽的动态变化和翻译后修饰的结构效应。具体而言，李教授和她的团队正在追求以下研究目标：(1)采用实验设计算法和更高复杂度的化学标签来扩大神经肽定量的分析通量；(2)将快速毛细管电泳分离与IM-MS结合，用于铜毒性和低氧/高碳酸血症的综合神经肽分析；(3)将“碰撞诱导展开”IM-MS与表面等离子体共振和分子动力学模拟相结合，深入分析肽外显子及其与受体相互作用的结构和构象；(4)构建大规模的神经肽异构体和糖基化神经肽碰撞截面（CCS）数据库，促进新型糖基化神经肽的功能发现和评价。该研究旨在推进测量科学并加速其应用，以解决有关信号肽在重金属毒性和缺氧的调节和适应中的功能作用的具有挑战性的生物学问题。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Professor Lingjun Li and her group at the University of Wisconsin-Madison are developing new analytical measurement tools to probe environmentally induced changes in neuropeptides. Specifically, the Li group seeks to exploit state-of-the-art analytical methods (mass spectrometry and ion mobility spectrometry) using chemical “tags” to enhance sensitivity and throughput during characterization and quantification of signaling peptides and their modifications in response to copper toxicity and hypoxia (oxygen deprivation) stress of cells. The technology being developed is expected to be transferable to the study of other biological systems. The molecular insights gained from the proposed studies have the potential to enhance understanding of normal and dysfunctional biology involving neuronal peptide signaling. This project provides excellent training opportunities for students who are interested in a career at the interface between chemical measurements and neuroscience. Dr. Li also works to bring awareness and participation in these research activities through partnership and outreach with high school internship programs that help to stimulate students’ interests in the STEM field at an early stage.The Li group seeks to develop an innovative analytical platform that integrates microseparations with ion mobility-mass spectrometry (IM-MS) and high-resolution MS to probe dynamic changes and structural effects of novel post-translational modifications of neuropeptides involved in copper toxicity, hypoxia, and hypercapnia. Specifically, Professor Li and her team are pursuing the following research goals: (1) to employ design-of-experiment algorithms and higher-plexing chemical tags to expand analytical throughput for neuropeptide quantitation; (2) to couple rapid capillary electrophoresis separation with IM-MS for comprehensive neuropeptide analysis in copper toxicity and hypoxia/hypercapnia; (3) to combine “collision-induced unfolding” IM-MS with surface plasmon resonance and molecular dynamics simulation for in-depth structural and conformational analysis of peptide epimers and their interaction with receptors; and (4) to construct a large-scale collision cross section (CCS) database for neuropeptide isoforms and glycosylated neuropeptides to facilitate functional discovery and evaluation of novel glycosylated neuropeptides. The research seeks to advance measurement science and accelerate its application to solve challenging biological questions regarding the functional roles of signaling peptides in the regulation and adaptation to heavy metal toxicity and hypoxia.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.