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Updated: Apr 28, 2026

Author Spotlight: Imaging ATG9A, a Multi-Spanning Membrane Protein
Published on: June 16, 2023
Atg1 kinase organizes autophagosome formation by phosphorylating Atg9
Daniel Papinski1, Claudine Kraft1
1Max F Perutz Laboratories; University of Vienna; Vienna, Austria.
Abstract:
The conserved Ser/Thr kinase Atg1/ULK1 plays a crucial role in the regulation of autophagy. However, only very few Atg1 targets have been identified, impeding elucidation of the mechanisms by which Atg1 regulates autophagy. In our study, we determined the Saccharomyces cerevisiae Atg1 consensus phosphorylation sequence using a peptide array-based approach. Among proteins containing this sequence we identified Atg9, another essential component of the autophagic machinery. We showed that phosphorylation of Atg9 by Atg1 is required for phagophore elongation, shedding light on the mechanism by which Atg1 regulates early steps of autophagy.
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