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Atg1-independent induction of autophagy by the Drosophila Ulk3 homolog, ADUK.

ABSTRACT: Although canonical autophagy regulation requires a multi-protein complex centered on the Ser/Thr-kinase Atg1 (mammalian Ulk1/2), alternative signals can induce autophagy independent of Atg1 through unknown mechanisms. Here we identify the Drosophila Ulk3 ortholog, another Drosophila Unc-51-like kinase (ADUK), as an Atg1-independent autophagy inducer. ADUK interacts with Atg1 complex members Atg13 and 200 kDa FAK family kinase-interacting protein, and requires Atg13 but not Atg1 for autophagy induction. Loss of ADUK shortens adult lifespan and reduces the autophagic response to a chemical stressor, dimethyl sulfoxide. However, ADUK is not required for autophagy induction by Atg1-dependent nutrient or developmental cues. Atg1 and ADUK/Ulk3 thus represent alternative catalytic components of a shared autophagy kinase complex.

SUBMITTER: Braden CR

PROVIDER: S-EPMC5123689 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Atg1-independent induction of autophagy by the Drosophila Ulk3 homolog, ADUK.

Braden Christopher R CR Neufeld Thomas P TP

The FEBS journal 20161011 21

Although canonical autophagy regulation requires a multi-protein complex centered on the Ser/Thr-kinase Atg1 (mammalian Ulk1/2), alternative signals can induce autophagy independent of Atg1 through unknown mechanisms. Here we identify the Drosophila Ulk3 ortholog, another Drosophila Unc-51-like kinase (ADUK), as an Atg1-independent autophagy inducer. ADUK interacts with Atg1 complex members Atg13 and 200 kDa FAK family kinase-interacting protein, and requires Atg13 but not Atg1 for autophagy ind ...[more]

PMID: 27717182

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