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Ubiquilin4 is an adaptor protein that recruits Ubiquilin1 to the autophagy machinery.

ABSTRACT: Ubiquilins (Ubqlns)-a family of ubiquitin-binding proteins-are involved in several protein degradation pathways and have been implicated in various neurodegenerative diseases. Ubqln1 regulates autophagosome maturation during autophagy-mediated degradation. We now show that Ubqln4 mediates the interaction between Ubqln1 and the autophagy machinery by recruiting Ubqln1 to LC3. This targeting of Ubqln1 to autophagosomes requires the Ubqln4 UBL domain and the Ubqln1 UBA domain. This study identifies a new role for Ubqln4, expanding the role for Ubqlns in protein degradation.

SUBMITTER: Lee DY

PROVIDER: S-EPMC3615663 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Ubiquilin4 is an adaptor protein that recruits Ubiquilin1 to the autophagy machinery.

Lee Dong Yun DY Arnott David D Brown Eric J EJ

EMBO reports 20130305 4

Ubiquilins (Ubqlns)-a family of ubiquitin-binding proteins-are involved in several protein degradation pathways and have been implicated in various neurodegenerative diseases. Ubqln1 regulates autophagosome maturation during autophagy-mediated degradation. We now show that Ubqln4 mediates the interaction between Ubqln1 and the autophagy machinery by recruiting Ubqln1 to LC3. This targeting of Ubqln1 to autophagosomes requires the Ubqln4 UBL domain and the Ubqln1 UBA domain. This study identifies ...[more]

PMID: 23459205

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