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bioRxiv · 10.64898/2026.07.24.740607

Integrin-dependent trafficking of CD98hc reduces endocytic noise to maintain metabolic homeostasis

Rizalar, F. S.·Grimm, H. P.·Augustin, A.·Garcia-Cordero, J. L.·Villasenor, R.
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Abstract

A stable supply of amino acids is essential for cellular homeostasis. CD98hc is an indispensable component of the LAT1 amino acid transporter. Here, we found an unexpected role for {beta}1-integrin in amino acid homeostasis via the regulation of CD98hc trafficking. We identified Fast Endophilin-Mediated Endocytosis (FEME) as the primary internalization route for CD98hc in both osteosarcoma and brain endothelial cells. Endocytosis was followed by {beta}1-integrin-dependent recycling, which diverted CD98hc from early endosomes. By combining mathematical modelling with high-content imaging, we demonstrate that this trafficking pathway exhibited emergent properties that filtered high-frequency endocytic events to stabilize CD98hc at the plasma membrane. Mutating CD98hc to disrupt its interaction with {beta}1-integrin led to redistribution of the transporter into early endosomes, reduced intracellular amino acid levels and impaired growth under metabolic stress. We propose that regulation of transporter trafficking dynamics is a general mechanism to buffer endocytic noise and maintain metabolic homeostasis.

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Rizalar, F. S., Grimm, H. P., Augustin, A., Garcia-Cordero, J. L., Villasenor, R.. 2026-07-27. Integrin-dependent trafficking of CD98hc reduces endocytic noise to maintain metabolic homeostasis. https://doi.org/10.64898/2026.07.24.740607

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