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bioRxiv · 10.1101/2023.07.23.550235

Endocytic vesicles act as vehicles for glucose uptake in response to growth factor stimulation

Tsutsumi, R.·Ueberheide, B.·Liang, F.-X.·Neel, B. G.·Sakai, R.·Saito, Y.
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Abstract

Glycolysis is a fundamental cellular process, yet its regulatory mechanisms remain incompletely understood. Here, we show that a subset of glucose transporter 1 (GLUT1/SLC2A1) co-endocytoses with platelet-derived growth factor (PDGF) receptor (PDGFR) upon PDGF-stimulation. Furthermore, multiple glycolytic enzymes localize to these endocytosed PDGFR/GLUT1-containing vesicles adjacent to mitochondria. Contrary to current models, which emphasize the importance of glucose transporters on the cell surface, we find that PDGF-stimulated glucose uptake depends on receptor/transporter endocytosis. Our results suggest that growth factors generate glucose-loaded endocytic vesicles that deliver glucose to the glycolytic machinery in proximity to mitochondria, and argue for a new layer of regulation for glycolytic control governed by cellular membrane dynamics.

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Tsutsumi, R., Ueberheide, B., Liang, F.-X., Neel, B. G., Sakai, R., Saito, Y.. 2023-07-24. Endocytic vesicles act as vehicles for glucose uptake in response to growth factor stimulation. https://doi.org/10.1101/2023.07.23.550235

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