Cargo-selective regulation of clathrin-mediated endocytosis by AMP-activated protein kinase

Orofiamma, L. A.; Delos Santos, R. C.; Mehrabi, A.; Leshchyshyn, N.; Hesketh, G. G.; Rahmani, S.; Patel, A.; Fekri, F.; Ata, R.; Ratcliffe, C. D.; Crupi, M. J.; Mulligan, L.; Park, M.; Gingras, A.-C.; Antonescu, C. N.

doi:10.1101/2024.11.05.622177

bioRxiv · 10.1101/2024.11.05.622177

Cargo-selective regulation of clathrin-mediated endocytosis by AMP-activated protein kinase

Orofiamma, L. A.·Delos Santos, R. C.·Mehrabi, A.·Leshchyshyn, N.·Hesketh, G. G.·Rahmani, S.·Patel, A.·Fekri, F.·Ata, R.·Ratcliffe, C. D.·Crupi, M. J.·Mulligan, L.·Park, M.·Gingras, A.-C.·Antonescu, C. N.

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Abstract

The cell surface abundance of many proteins is controlled by clathrin-mediated endocytosis (CME). CME is driven by the assembly of clathrin and other proteins on the inner leaflet of the plasma membrane into clathrin-coated pits (CCPs). Regulation of CCP dynamics allows for control of the function of specific cell surface proteins, impacting a range of cellular outcomes. AMP-activated protein kinase (AMPK) becomes activated upon metabolic insufficiency and facilitates cellular adaptation to nutrient stress. Here, we examined how AMPK regulates CME and the cell surface membrane traffic of {beta}1-integrin. We find that AMPK controls CCP dynamics and regulates the abundance of the endocytic adaptor protein Dab2 within CCPs in a manner that requires the GTPase Arf6, thus selectively promoting the CCP recruitment and internalization of {beta}1-integrin. This reveals a novel signaling pathway for cargo-selective metabolic regulation of CME by AMPK, impacting the function of cell surface proteins such as integrins.

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Orofiamma, L. A., Delos Santos, R. C., Mehrabi, A., Leshchyshyn, N., Hesketh, G. G., Rahmani, S., Patel, A., Fekri, F., Ata, R., Ratcliffe, C. D., Crupi, M. J., Mulligan, L., Park, M., Gingras, A.-C., Antonescu, C. N.. 2024-11-06. Cargo-selective regulation of clathrin-mediated endocytosis by AMP-activated protein kinase. https://doi.org/10.1101/2024.11.05.622177

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