6HOJ

Structure of Beclin1 LIR motif bound to GABARAP

Summary for 6HOJ

• Entry DOI: 10.2210/pdb6hoj/pdb
• Descriptor: Beclin-1,Gamma-aminobutyric acid receptor-associated protein, SULFATE ION, 1,2-ETHANEDIOL, ... (4 entities in total)
• Functional Keywords: autophagy, atg8, lir, signaling protein
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 3
• Total formula weight: 44737.91

Authors

Mouilleron, S.,Birgisdottir, A.B.,Bhujbal, Z.,Wirth, M.,Sjottem, E.,Evjen, G.,Zhang, W.,Lee, R.,O'Reilly, N.,Tooze, S.,Lamark, T.,Johansen, T. (deposition date: 2018-09-17, release date: 2019-02-27, Last modification date: 2024-05-15)

Primary citation

Birgisdottir, A.B.,Mouilleron, S.,Bhujabal, Z.,Wirth, M.,Sjottem, E.,Evjen, G.,Zhang, W.,Lee, R.,O'Reilly, N.,Tooze, S.A.,Lamark, T.,Johansen, T.
Members of the autophagy class III phosphatidylinositol 3-kinase complex I interact with GABARAP and GABARAPL1 via LIR motifs.
Autophagy, 15:1333-1355, 2019

PubMed Abstract: Autophagosome formation depends on a carefully orchestrated interplay between membrane-associated protein complexes. Initiation of macroautophagy/autophagy is mediated by the ULK1 (unc-51 like autophagy activating kinase 1) protein kinase complex and the autophagy-specific class III phosphatidylinositol 3-kinase complex I (PtdIns3K-C1). The latter contains PIK3C3/VPS34, PIK3R4/VPS15, BECN1/Beclin 1 and ATG14 and phosphorylates phosphatidylinositol to generate phosphatidylinositol 3-phosphate (PtdIns3P). Here, we show that PIK3C3, BECN1 and ATG14 contain functional LIR motifs and interact with the Atg8-family proteins with a preference for GABARAP and GABARAPL1. High resolution crystal structures of the functional LIR motifs of these core components of PtdIns3K-C1were obtained. Variation in hydrophobic pocket 2 (HP2) may explain the specificity for the GABARAP family. Mutation of the LIR motif in ATG14 did not prevent formation of the PtdIns3K-C1 complex, but blocked colocalization with MAP1LC3B/LC3B and impaired mitophagy. The ULK-mediated phosphorylation of S29 in ATG14 was strongly dependent on a functional LIR motif in ATG14. GABARAP-preferring LIR motifs in PIK3C3, BECN1 and ATG14 may, via coincidence detection, contribute to scaffolding of PtdIns3K-C1 on membranes for efficient autophagosome formation. ATG: autophagy-related; BafA1: bafilomycin A; GABARAP: GABA type A receptor-associated protein; GABARAPL1: GABA type A receptor associated protein like 1; GFP: enhanced green fluorescent protein; KO: knockout; LDS: LIR docking site; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; PIK3C3: phosphatidylinositol 3-kinase catalytic subunit type 3; PIK3R4: phosphoinositide-3-kinase regulatory subunit 4; PtdIns3K: phosphatidylinositol 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; SQSTM1/p62: sequestosome 1; VPS: Vacuolar protein sorting; ULK: unc-51 like autophagy activating kinase.

PubMed: 30767700
DOI: 10.1080/15548627.2019.1581009

Experimental method

X-RAY DIFFRACTION (1.51 Å)