| Structural highlights
6hog is a 1 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | , , |
| Gene: | GABARAP, FLC3B, HT004 (HUMAN) |
| Activity: | Phosphatidylinositol 3-kinase, with EC number 2.7.1.137 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[PK3C3_HUMAN] Catalytic subunit of the PI3K complex that mediates formation of phosphatidylinositol 3-phosphate which plays a key role in initiation and maturation of autophagosomes. Involved in the transport of lysosomal enzyme precursors to lysosomes. Required for the abcission step in cytokinesis. Required for transport from early to late endosomes.[1] [2] [3]
Publication Abstract from PubMed
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.
Members of the autophagy class III phosphatidylinositol 3-kinase complex I interact with GABARAP and GABARAPL1 via LIR motifs.,Birgisdottir AB, Mouilleron S, Bhujabal Z, Wirth M, Sjottem E, Evjen G, Zhang W, Lee R, O'Reilly N, Tooze SA, Lamark T, Johansen T Autophagy. 2019 Feb 15. doi: 10.1080/15548627.2019.1581009. PMID:30767700[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Volinia S, Dhand R, Vanhaesebroeck B, MacDougall LK, Stein R, Zvelebil MJ, Domin J, Panaretou C, Waterfield MD. A human phosphatidylinositol 3-kinase complex related to the yeast Vps34p-Vps15p protein sorting system. EMBO J. 1995 Jul 17;14(14):3339-48. PMID:7628435
- ↑ Stein MP, Feng Y, Cooper KL, Welford AM, Wandinger-Ness A. Human VPS34 and p150 are Rab7 interacting partners. Traffic. 2003 Nov;4(11):754-71. PMID:14617358
- ↑ Sagona AP, Nezis IP, Pedersen NM, Liestol K, Poulton J, Rusten TE, Skotheim RI, Raiborg C, Stenmark H. PtdIns(3)P controls cytokinesis through KIF13A-mediated recruitment of FYVE-CENT to the midbody. Nat Cell Biol. 2010 Apr;12(4):362-71. doi: 10.1038/ncb2036. Epub 2010 Mar 7. PMID:20208530 doi:http://dx.doi.org/10.1038/ncb2036
- ↑ Birgisdottir AB, Mouilleron S, Bhujabal Z, Wirth M, Sjottem E, Evjen G, Zhang W, Lee R, O'Reilly N, Tooze SA, Lamark T, Johansen T. Members of the autophagy class III phosphatidylinositol 3-kinase complex I interact with GABARAP and GABARAPL1 via LIR motifs. Autophagy. 2019 Feb 15. doi: 10.1080/15548627.2019.1581009. PMID:30767700 doi:http://dx.doi.org/10.1080/15548627.2019.1581009
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