Lysosome damage triggers acute formation of ER to lysosomes membrane tethers mediated by the bridge-like lipid transport protein VPS13C

Wang, X.; Xu, P.; Bentley-DeSousa, A.; Hancock-Cerutti, W.; Cai, S.; Johnson, B. T.; Tonelli, F.; Talaia, G.; Alessi, D. R.; Ferguson, S. M.; De Camilli, P.

doi:10.1101/2024.06.08.598070

bioRxiv · 10.1101/2024.06.08.598070

Lysosome damage triggers acute formation of ER to lysosomes membrane tethers mediated by the bridge-like lipid transport protein VPS13C

Wang, X.·Xu, P.·Bentley-DeSousa, A.·Hancock-Cerutti, W.·Cai, S.·Johnson, B. T.·Tonelli, F.·Talaia, G.·Alessi, D. R.·Ferguson, S. M.·De Camilli, P.

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Abstract

Based on genetic studies, lysosome dysfunction is thought to play a pathogenetic role in Parkinsons disease (PD). Here we show that VPS13C, a bridge-like lipid transport protein and a PD gene, is a sensor of lysosome stress/damage. Upon lysosome membrane perturbation, VPS13C rapidly relocates from the cytosol to the surface of lysosomes where it tethers their membranes to the ER. This recruitment depends on Rab7 and requires a signal at the damaged lysosome surface that releases an inhibited state of VPS13C which hinders access of its VAB domain to lysosome-bound Rab7. While another PD protein, LRRK2, is also recruited to stressed/damaged lysosomes, its recruitment occurs at much later stages and by different mechanisms. Given the role of VPS13 proteins in bulk lipid transport, these findings suggest that lipid delivery to lysosomes by VPS13C is part of an early protective response to lysosome damage.

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Wang, X., Xu, P., Bentley-DeSousa, A., Hancock-Cerutti, W., Cai, S., Johnson, B. T., Tonelli, F., Talaia, G., Alessi, D. R., Ferguson, S. M., De Camilli, P.. 2024-06-08. Lysosome damage triggers acute formation of ER to lysosomes membrane tethers mediated by the bridge-like lipid transport protein VPS13C. https://doi.org/10.1101/2024.06.08.598070

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