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Atg3 promotes Atg8 lipidation via altering lipid diffusion and rearrangement.

ABSTRACT: Atg3-catalyzed transferring of Atg8 to phosphatidylethanolamine (PE) in the phagophore membrane is essential for autophagy. Previous studies have demonstrated that this process requires Atg3 to interact with the phagophore membrane via its N-terminal amphipathic helix. In this study, by using combined biochemical and biophysical approaches, our data showed that in addition to binding to the membranes, Atg3 attenuates lipid diffusion and enriches lipid molecules with smaller headgroup. Our data suggest that Atg3 promotes Atg8 lipidation via altering lipid diffusion and rearrangement.

SUBMITTER: Wang S

PROVIDER: S-EPMC7255502 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Atg3 promotes Atg8 lipidation via altering lipid diffusion and rearrangement.

Wang Shen S Li Yun Y Ma Cong C

Protein science : a publication of the Protein Society 20200420 6

Atg3-catalyzed transferring of Atg8 to phosphatidylethanolamine (PE) in the phagophore membrane is essential for autophagy. Previous studies have demonstrated that this process requires Atg3 to interact with the phagophore membrane via its N-terminal amphipathic helix. In this study, by using combined biochemical and biophysical approaches, our data showed that in addition to binding to the membranes, Atg3 attenuates lipid diffusion and enriches lipid molecules with smaller headgroup. Our data s ...[more]

PMID: 32277540

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