Journal Article Ppublish
PubMed: 40554698 DOI: 10.1021/jasms.4c00500
Endogenous Aquaporin-0 Lipid Binding in Ocular Lens Tissue via Native Mass Spectrometry.
J Am Soc Mass Spectrom 36(8):1588-1597
Authors: Carla V T O'Neale, Sophie R Harvey, Sergei Chetyrkin, Vicki H Wysocki, Kevin L Schey
Affiliations
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee 37205, United States.
- Department of Chemistry and Biochemistry and Native Mass Spectrometry Guided Structural Biology Center, The Ohio State University, Columbus, Ohio 43210, United States.
- Mass Spectrometry Research Center, Vanderbilt University, Nashville, Tennessee 37240, United States.
- School of Chemistry and Biochemistry, Georgia Tech, Atlanta, Georgia 30332, United States.
Abstract
The ocular lens microcirculation system (MCS) is required to maintain transparency; however, how this system is established and maintained as a function of age is not well understood. Through its role in cell adhesion and water permeability, Aquaporin-0 (AQP0) is an important protein in the generation and regulation of the MCS. AQP0 permeability studies have shown that the lipid composition surrounding AQP0 has a direct effect on its function; nevertheless, interactions of native lens lipids with AQP0 have yet to be elucidated. In this study, we used native mass spectrometry (nMS) analysis of ocular lens membrane preparations to identify endogenous lipids bound to AQP0 to inform our understanding of how AQP0-lipid interactions regulate AQP0 function in the lens. We found that a variety of endogenous lens lipids (phosphatidylcholines (PCs) and sphingomyelins (SMs)) differentially bind AQP0 in a regionally dependent manner (cortex vs nucleus). Furthermore, spike-in experiments using native lens lipid extracts allowed us to uncover new AQP0-lipid assemblies not detected in the crude AQP0 experiments, including AQP0-ether-linked PC and AQP0-SM interactions.
MeSH
Aquaporins, Tissues