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bioRxiv · 10.64898/2026.03.23.713624

Starvation-induced autophagy occurs independently of the ATG1 complex in Chlamydomonas

Zou, Y.·Wu, Y.·Stael, S.·Moschou, P. N.·Zhuang, X.·Minina, A. E. A.·Bozhkov, P.
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Abstract

The survival of eukaryotes during starvation depends on effective nutrient recycling via autophagy. Accordingly, loss of autophagy-related (ATG) proteins, including the nutrient-sensing ATG1 kinase complex, typically results in reduced fitness or lethality under nutrient limitation. The green alga Chlamydomonas reinhardtii provides a tractable model for autophagy studies, as its ATG repertoire is encoded by single-copy genes. Here, we generated a comprehensive library of ATG deletion mutants and examined their growth and autophagy during starvation. Surprisingly, starvation-induced autophagy occurred in the absence of ATG1 complex components (ATG1, ATG11, ATG13, and ATG101), revealing ATG1-independent autophagy and challenging the canonical model for autophagy initiation.

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Zou, Y., Wu, Y., Stael, S., Moschou, P. N., Zhuang, X., Minina, A. E. A., Bozhkov, P.. 2026-03-25. Starvation-induced autophagy occurs independently of the ATG1 complex in Chlamydomonas. https://doi.org/10.64898/2026.03.23.713624

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