title: The Nedd4-like ubiquitin E3 ligases target angiomotin/p130 to ubiquitin-dependent degradation.
abstract: AMOT (angiomotin) is a membrane-associated protein that is expressed in ECs (endothelial cells) and controls migration, TJ (tight junction) formation, cell polarity and angiogenesis. Recent studies have revealed that AMOT and two AMOT-like proteins, AMOTL1 and AMOTL2, play critical roles in the Hippo pathway by regulating the subcellular localization of the co-activators YAP (Yes-associated protein) and TAZ (transcriptional co-activator with PDZ-binding motif). However, it has been unclear how AMOT is regulated. In the present study, we report that AMOT undergoes proteasomal degradation. We identify three members of Nedd4 (neural-precursor-cell-expressed developmentally down-regulated)-like ubiquitin E3 ligases, Nedd4, Nedd4-2 and Itch, as the ubiquitin E3 ligases for the long isoform of AMOT, AMOT/p130. We demonstrate that Nedd4, Nedd4-2 and Itch mediate poly-ubiquitination of AMOT/p130 in vivo. Overexpression of Nedd4, Nedd4-2 or Itch leads to AMOT/p130 proteasomal degradation. Knockdown of Nedd4, Nedd4-2 and Itch causes an accumulation of steady-state level of AMOT/p130. We also show that three L/P-PXY motifs of AMOT/p130 and the WW domains of Nedd4 mediate their interaction. Furthermore, Nedd4-like ubiquitin E3 ligases might compete with YAP for the binding to AMOT/p130, and subsequently targeting AMOT/p130 for ubiquitin-dependent degradation. Together, these observations reveal a novel post-translational regulatory mechanism of AMOT/p130.
authors.affiliation: State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, PR China.
authors.forename: Chenji
authors.initials: C
authors.lastname: Wang
authors.forename: Jian
authors.initials: J
authors.lastname: An
authors.forename: Pingzhao
authors.initials: P
authors.lastname: Zhang
authors.forename: Chen
authors.initials: C
authors.lastname: Xu
authors.forename: Kun
authors.initials: K
authors.lastname: Gao
authors.forename: Di
authors.initials: D
authors.lastname: Wu
authors.forename: Dejie
authors.initials: D
authors.lastname: Wang
authors.forename: Hongxiu
authors.initials: H
authors.lastname: Yu
authors.forename: Jun O
authors.initials: JO
authors.lastname: Liu
authors.forename: Long
authors.initials: L
authors.lastname: Yu
mesh_terms: D000595:Amino Acid Sequence; D000091082:Angiomotins; D056827:Endosomal Sorting Complexes Required for Transport / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D055785:Gene Knockdown Techniques; D057809:HEK293 Cells; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008840:Microfilament Proteins; D008969:Molecular Sequence Data; D000075702:Nedd4 Ubiquitin Protein Ligases; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D020033:Protein Isoforms / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D059748:Proteolysis; D012097:Repressor Proteins / Q000096:biosynthesis / Q000172:deficiency / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics; D025801:Ubiquitin / Q000235:genetics / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000096:biosynthesis / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D054875:Ubiquitination / Q000235:genetics
chemical_list: C423985:AMOT protein, human; D000091082:Angiomotins; D056827:Endosomal Sorting Complexes Required for Transport; D036341:Intercellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D008840:Microfilament Proteins; D020033:Protein Isoforms; D012097:Repressor Proteins; D025801:Ubiquitin; C432966:ITCH protein, human; D000075702:Nedd4 Ubiquitin Protein Ligases; C000618483:Nedd4 protein, human; C000618485:Nedd4L protein, human; D044767:Ubiquitin-Protein Ligases; D046988:Proteasome Endopeptidase Complex