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bioRxiv · 10.1101/2020.12.30.424839

Evidence for nutrient-dependent regulation of the COPII coat by O-GlcNAcylation

Bisnett, B. J.·Condon, B. M.·Linhart, N. A.·Lamb, C. H.·Huynh, D. T.·Bai, J.·Smith, T. J.·Hu, J.·Georgiou, G. R.·Boyce, M.
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Abstract

O-linked {beta}-N-acetylglucosamine (O-GlcNAc) is a dynamic form of intracellular glycosylation common in animals, plants and other organisms. O-GlcNAcylation is essential in mammalian cells and is dysregulated in myriad human diseases, such as cancer, neurodegeneration and metabolic syndrome. Despite this pathophysiological significance, key aspects of O-GlcNAc signaling remain incompletely understood, including its impact on fundamental cell biological processes. Here, we investigate the role of O-GlcNAcylation in the coat protein II complex (COPII), a system universally conserved in eukaryotes that mediates anterograde vesicle trafficking from the endoplasmic reticulum. We identify new O-GlcNAcylation sites on Sec24C, Sec24D and Sec31A, core components of the COPII system, and provide evidence for potential nutrient-sensitive pathway regulation through site-specific glycosylation. Our work suggests a new connection between metabolism and trafficking through the conduit of COPII protein O-GlcNAcylation.

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Bisnett, B. J., Condon, B. M., Linhart, N. A., Lamb, C. H., Huynh, D. T., Bai, J., Smith, T. J., Hu, J., Georgiou, G. R., Boyce, M.. 2020-12-30. Evidence for nutrient-dependent regulation of the COPII coat by O-GlcNAcylation. https://doi.org/10.1101/2020.12.30.424839

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