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

在化学系化学测量和成像项目的支持下，威斯康星大学麦迪逊分校的李凌军教授和她的团队正在开发新的分析测量工具，以探索环境诱导的神经肽变化。具体地说，LI团队寻求利用最先进的分析方法(质谱仪和离子迁移率光谱)，使用化学“标签”来提高表征和量化信号肽及其修饰物的灵敏度和吞吐量，以响应细胞的铜中毒和缺氧(缺氧)压力。正在开发的技术有望转移到其他生物系统的研究中。从拟议的研究中获得的分子洞察力有可能加强对涉及神经肽信号的正常和功能失调生物学的理解。该项目为对化学测量和神经科学之间的职业感兴趣的学生提供了极好的培训机会。李博士还致力于通过与高中实习项目的合作和接触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。李博士团队致力于开发一个创新的分析平台，将微分离与离子迁移率-质谱仪(IM-MS)和高分辨率MS相结合，以探索与铜中毒、低氧和高碳酸血症相关的神经肽的新型翻译后修饰的动态变化和结构效应。具体地说，李教授和她的团队正在追求以下研究目标：(1)利用实验设计算法和更复杂的化学标记来扩大神经肽定量的分析吞吐量；(2)将快速毛细管电泳法与IM-MS结合起来，用于铜中毒和低氧/高碳酸血症的全面神经肽分析；(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，深入分析多肽同分异构体及其与受体的相互作用；(4)建立神经肽异构体和糖基化神经肽的大规模碰撞截面(CCS)数据库，为新的糖基化神经肽的功能发现和评价提供便利。这项研究旨在推进测量科学并加速其应用，以解决与信号肽在调节和适应重金属毒性和低氧中的功能作用有关的具有挑战性的生物学问题。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.