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

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.