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Solution structure of the Atg1 complex: implications for the architecture of the phagophore assembly site.

ABSTRACT: The biogenesis of autophagosomes commences at the phagophore assembly site (PAS), a protein-vesicle ultrastructure that is organized by the Atg1 complex. The Atg1 complex consists of the Atg1 protein kinase, the intrinsically disordered region-rich Atg13, and the dimeric double crescent-shaped Atg17-Atg31-Atg29 subcomplex. We show that the PAS contains a relatively uniform ?28 copies of Atg17, and upon autophagy induction, similar numbers of Atg1 and Atg13 molecules. We then apply ensemble refinement of small-angle X-ray scattering to determine the solution structures of the Atg1-Atg13 and Atg17-Atg31-Atg29 subcomplexes and the Atg1 complex, using a trimmed minipentamer tractable to biophysical studies. We observe tetramers of Atg1 pentamers that assemble via Atg17-Atg31-Atg29. This leads to a model for the higher organization of the Atg1 complex in PAS scaffolding.

SUBMITTER: Kofinger J

PROVIDER: S-EPMC4426065 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Solution structure of the Atg1 complex: implications for the architecture of the phagophore assembly site.

Köfinger Jürgen J Ragusa Michael J MJ Lee Il-Hyung IH Hummer Gerhard G Hurley James H JH

Structure (London, England : 1993) 20150326 5

The biogenesis of autophagosomes commences at the phagophore assembly site (PAS), a protein-vesicle ultrastructure that is organized by the Atg1 complex. The Atg1 complex consists of the Atg1 protein kinase, the intrinsically disordered region-rich Atg13, and the dimeric double crescent-shaped Atg17-Atg31-Atg29 subcomplex. We show that the PAS contains a relatively uniform ∼28 copies of Atg17, and upon autophagy induction, similar numbers of Atg1 and Atg13 molecules. We then apply ensemble refin ...[more]

PMID: 25817386

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Solution structure of the Atg1 complex: implications for the architecture of the phagophore assembly site.

Publications

Solution structure of the Atg1 complex: implications for the architecture of the phagophore assembly site.

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