Tandem-Trapped Ion Mobility Spectrometry for Characterizing Structure and Function of Proteoforms

Cellular processes depend on the coordinated function of all proteoforms—the distinct molecular forms of a protein that arise from mechanisms such as alternative splicing and post-translational modifications. Different proteoforms can have distinct free energy landscapes that may alter their structures, motions, and interactions with other proteins. As a result, changes in proteoforms can alter cellular regulation and lead to dysfunctions associated with diseases such as cancer. To investigate how proteoform variations impact protein structure and function, my lab is developing novel computational and experimental ion mobility/mass spectrometry approaches. In this lecture, I will begin by outlining the development of our tandem-trapped ion mobility spectrometry/tandem-mass spectrometry (tandem-TIMS/tandem-MS) and molecular dynamics-based structure relaxation approximation (SRA) methods. I will then discuss how these techniques can be leveraged to characterize protein primary and higher-order structures. Finally, I will examine how these methods facilitate the analysis of the relationship between glycosylation and the higher-order structures of antibodies and viral spike proteins.