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HUNK Phosphorylates Rubicon to Support Autophagy.

ABSTRACT: BACKGROUND:Autophagy is a catabolic cellular recycling pathway that is essential for maintaining intracellular homeostasis. Autophagosome formation is achieved via the coordination of the Beclin-1 protein complex. Rubicon is a Beclin-1 associated protein that suppresses autophagy by impairing the activity of the class III PI3K, Vps34. However, very little is known about the molecular mechanisms that regulate Rubicon function. METHODS:In this study, co-immunoprecipitation and kinase assays were used to investigate the ability of Hormonally Upregulated Neu-associated Kinase (HUNK) to bind to and phosphorylate Rubicon. LC3B was monitored by immunofluorescence and immunoblotting to determine whether phosphorylation of Rubicon by HUNK controls the autophagy suppressive function of Rubicon. RESULTS:Findings from this study identify Rubicon as a novel substrate of HUNK and show that phosphorylation of Rubicon inhibits its function, promoting autophagy.

SUBMITTER: Zambrano JN

PROVIDER: S-EPMC6888122 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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HUNK Phosphorylates Rubicon to Support Autophagy.

Zambrano Joelle N JN Eblen Scott T ST Abt Melissa M Rhett J Matthew JM Muise-Helmericks Robin R Yeh Elizabeth S ES

International journal of molecular sciences 20191119 22

<h4>Background</h4>Autophagy is a catabolic cellular recycling pathway that is essential for maintaining intracellular homeostasis. Autophagosome formation is achieved via the coordination of the Beclin-1 protein complex. Rubicon is a Beclin-1 associated protein that suppresses autophagy by impairing the activity of the class III PI3K, Vps34. However, very little is known about the molecular mechanisms that regulate Rubicon function.<h4>Methods</h4>In this study, co-immunoprecipitation and kinas ...[more]

PMID: 31752345

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