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The mammalian autophagy initiator complex contains 2 HORMA domain proteins.

ABSTRACT: ATG101 is an essential component of the ULK complex responsible for initiating cellular autophagy in mammalian cells; its 3-dimensional structure and molecular function, however, are currently unclear. Here we present the X-ray structure of human ATG101. The protein displays an open HORMA domain fold. Both structural properties and biophysical evidence indicate that ATG101 is locked in this conformation, in contrast to the prototypical HORMA domain protein MAD2. Moreover, we discuss a potential mode of dimerization with ATG13 as a fundamental aspect of ATG101 function.

SUBMITTER: Michel M

PROVIDER: S-EPMC4835198 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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The mammalian autophagy initiator complex contains 2 HORMA domain proteins.

Michel Max M Schwarten Melanie M Decker Christina C Nagel-Steger Luitgard L Willbold Dieter D Weiergräber Oliver H OH

Autophagy 20150101 12

ATG101 is an essential component of the ULK complex responsible for initiating cellular autophagy in mammalian cells; its 3-dimensional structure and molecular function, however, are currently unclear. Here we present the X-ray structure of human ATG101. The protein displays an open HORMA domain fold. Both structural properties and biophysical evidence indicate that ATG101 is locked in this conformation, in contrast to the prototypical HORMA domain protein MAD2. Moreover, we discuss a potential ...[more]

PMID: 26236954

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