title: Regulation of WASH-dependent actin polymerization and protein trafficking by ubiquitination.
abstract: Endosomal protein trafficking is an essential cellular process that is deregulated in several diseases and targeted by pathogens. Here, we describe a role for ubiquitination in this process. We find that the E3 RING ubiquitin ligase, MAGE-L2-TRIM27, localizes to endosomes through interactions with the retromer complex. Knockdown of MAGE-L2-TRIM27 or the Ube2O E2 ubiquitin-conjugating enzyme significantly impaired retromer-mediated transport. We further demonstrate that MAGE-L2-TRIM27 ubiquitin ligase activity is required for nucleation of endosomal F-actin by the WASH regulatory complex, a known regulator of retromer-mediated transport. Mechanistic studies showed that MAGE-L2-TRIM27 facilitates K63-linked ubiquitination of WASH K220. Significantly, disruption of WASH ubiquitination impaired endosomal F-actin nucleation and retromer-dependent transport. These findings provide a cellular and molecular function for MAGE-L2-TRIM27 in retrograde transport, including an unappreciated role of K63-linked ubiquitination and identification of an activating signal of the WASH regulatory complex.
authors: Department of Physiology, UT Southwestern Dallas, TX 75390, USA.
authors: Yi-Heng
authors: YH
authors: Hao
authors: Jennifer M
authors: JM
authors: Doyle
authors: Saumya
authors: S
authors: Ramanathan
authors: Timothy S
authors: TS
authors: Gomez
authors: Da
authors: D
authors: Jia
authors: Ming
authors: M
authors: Xu
authors: Zhijian J
authors: ZJ
authors: Chen
authors: Daniel D
authors: DD
authors: Billadeau
authors: Michael K
authors: MK
authors: Rosen
authors: Patrick Ryan
authors: PR
authors: Potts
mesh_terms: D000199:Actins / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism; D055785:Gene Knockdown Techniques; D006056:Golgi Apparatus / Q000378:metabolism; D006801:Humans; D008840:Microfilament Proteins / Q000378:metabolism; D046912:Multiprotein Complexes / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D044763:Ubiquitin-Conjugating Enzymes / Q000378:metabolism; D054875:Ubiquitination; D047908:Intracellular Signaling Peptides and Proteins; D064267:Intrinsically Disordered Proteins; D000070584:Tripartite Motif Proteins
chemical_list: D000199:Actins; D004268:DNA-Binding Proteins; D008840:Microfilament Proteins; D046912:Multiprotein Complexes; D009687:Nuclear Proteins; D011506:Proteins; D044763:Ubiquitin-Conjugating Enzymes; C510822:MAGEL2 protein, human; D047908:Intracellular Signaling Peptides and Proteins; D064267:Intrinsically Disordered Proteins; C064419:TRIM27 protein, human; D000070584:Tripartite Motif Proteins; C549919:WASH protein, human