Metabolic Control of Glycosylation Forms for Establishing Glycan-Dependent Protein Interaction Networks

Liu, X.; Yi, L.; Lin, Z.; Chen, S.; Wang, S.; Sheng, Y.; Lebrilla, C. B.; Garcia, B. A.; Xie, Y.

doi:10.1101/2024.10.30.621210

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bioRxiv · 10.1101/2024.10.30.621210

Metabolic Control of Glycosylation Forms for Establishing Glycan-Dependent Protein Interaction Networks

Liu, X.·Yi, L.·Lin, Z.·Chen, S.·Wang, S.·Sheng, Y.·Lebrilla, C. B.·Garcia, B. A.·Xie, Y.

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Abstract

Protein-protein interactions (PPIs) provide essential insights into the complex molecular mechanisms and signaling pathways within cells that regulate development and disease-related phenotypes. However, for membrane proteins, the impact of various forms of glycosylation has often been overlooked in PPI studies. In this study, we introduce a novel approach, glycan-dependent affinity purification followed by mass spectrometry (GAP-MS), to assess variations in PPIs for any glycoprotein of interest under different glycosylation conditions. As a proof of principle, we selected four glycoproteins--BSG, CD44, EGFR, and SLC3A2--as baits to compare their co-purified partners across five metabolically controlled glycan conditions. The findings demonstrate the capability of GAP-MS to identify PPIs influenced by altered glycosylation states, establishing a foundation for systematically exploring the Glycan-Dependent Protein Interactome (GDPI) for other glycoproteins of interest.

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Liu, X., Yi, L., Lin, Z., Chen, S., Wang, S., Sheng, Y., Lebrilla, C. B., Garcia, B. A., Xie, Y.. 2024-11-01. Metabolic Control of Glycosylation Forms for Establishing Glycan-Dependent Protein Interaction Networks. https://doi.org/10.1101/2024.10.30.621210

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