Scratching the surface: native mass spectrometry of peripheral membrane protein complexes

Abstract

A growing number of integral membrane proteins have been shown to tune their activity by selectively interacting with specific lipids. The ability to regulate biological functions via lipid interactions extends to the diverse group of proteins that associate only peripherally with the lipid bilayer. However, the structural basis of these interactions remains challenging to study due to their transient and promiscuous nature. Recently, native mass spectrometry has come into focus as a new tool to investigate lipid interactions in membrane proteins. Here, we outline how the native MS strategies developed for integral membrane proteins can be applied to generate insights into the structure and function of peripheral membrane proteins. Specifically, native MS studies of proteins in complex with detergent-solubilized lipids, bound to lipid nanodiscs, and released from native-like lipid vesicles all shed new light on the role of lipid interactions. The unique ability of native MS to capture and interrogate protein–protein, protein–ligand, and protein–lipid interactions opens exciting new avenues for the study of peripheral membrane protein biology.

The more the merrier: effects of macromolecular crowding on the structure and dynamics of biological membranes

“…Membrane proteins constitute large part of cellular membranes and include not only integral proteins with transmembrane domains, but also soluble proteins peripherally bound to lipid leaflets via lipid anchors, hydrophobic interfaces or amphipathic helices, or docked on transmembrane proteins to form functional complexes [19,20]. The membrane proteome is highly dynamic, and substantial changes upon the development of pathologies, viral infections and between primary and immortalized cell cultures have been described [21][22][23].…”

Nanodiscs: A toolkit for membrane protein science

“…Recent progress in native mass‐spectrometry, in collaboration with Professor M. Gross, enabled the direct counting of lipids in Nanodiscs 95,96 . The next step applied this method to studies of membrane proteins and peptides in Nanodiscs, as described in several original papers and reviews 97–99 . An elegant extension of Nanodisc technology for mass‐spectrometry applications via generation of the mutant MSP was designed in order to change total Nanodisc mass and to improve resolution of overlapping species in a single spectrum 100 .…”

Liposomes as Carriers of Membrane‐Associated Proteins and Peptides for Mass Spectrometric Analysis

“…[5][6][7] This was initially achieved by dissociating the detergent micelle and releasing the free protein into the mass spectrometer. [8] Later studies reconstituted membrane proteins in amphipols,b icelles,o r various types of nanodiscs [9][10][11][12] and showed that the native oligomeric states of the proteins [10,13] as well as protein-lipid interactions [13,14] are accessible by MS when using membrane mimetics.Arecent breakthrough was the analysis of proteinligand assemblies directly from native membrane vesicles. [15] To study membrane association of peripheral membrane proteins,nanodiscs,and liposomes proved promising in recent studies.…”