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bioRxiv · 10.1101/2024.07.26.605287

Reticulon dependent ER-phagy mediates adaptation to heat stress in Caenorhabditis elegans

Scarcelli, V.·Serot, C.·Pouget, A.·Largeau, C.·Sagot, A.·El-Hachimi, K.·Dupuy, D.·Culetto, E.·Lefebvre, C.·Legouis, R.
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Abstract

The selective degradation of ER by autophagy, named ER-phagy, promotes the recovery of ER homeostasis after a stress. Depending on the ER stress, different types of ER-phagy involve various selective autophagy receptors. In this study, we report a macroER-phagy induced by the fragmentation of tubular ER in response to acute heat stress. We identified a novel ER-phagy receptor encoded by the reticulon long isoform RET-1d. RET-1d is mainly expressed in the nervous system and the epidermis and colocalize with the ubiquitin-like autophagy protein LGG-1/GABARAP during heat stress induced autophagy. Two LIR motifs in the long intrinsically disordered region of RET-1d mediate its interaction with LGG-1 protein. The specific depletion of RET-1d isoform resulted in a delay in autophagosome biogenesis and a decrease in the capacity of animals to adapt to heat stress. Our data revealed a RET-1d dependent ER-phagy mechanism that takes place in neurons and epidermis and participates to the adaptation of C. elegans to heat stress.

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Scarcelli, V., Serot, C., Pouget, A., Largeau, C., Sagot, A., El-Hachimi, K., Dupuy, D., Culetto, E., Lefebvre, C., Legouis, R.. 2024-07-26. Reticulon dependent ER-phagy mediates adaptation to heat stress in Caenorhabditis elegans. https://doi.org/10.1101/2024.07.26.605287

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