title: The CUL3-SPOP-DAXX axis is a novel regulator of VEGFR2 expression in vascular endothelial cells.
abstract: Vascular endothelial cell growth factor receptor 2 (VEGFR2) is an essential receptor for the homeostasis of endothelial cells. In this study, we showed that NEDD8-conjugated Cullin3 (CUL3)-based ubiquitin E3 (UbE3) ligase plays a crucial role in VEGFR2 mRNA expression. Human umbilical vein endothelial cells treated with MLN4924, an inhibitor of NEDD8-activating enzyme, or with CUL3 siRNA drastically lost their response to VEGF due to the intense decrease in VEGFR2 expression. Moreover, speckle-type POZ protein (SPOP) and death-domain associated protein (DAXX) were involved in the CUL3 UbE3 ligase complex as a substrate adaptor and a substrate, respectively. Knockdown of SPOP and CUL3 led to the upregulation of DAXX protein and downregulation of VEGFR2 levels. These levels were inversely correlated with one another. In addition, simultaneous knockdown of SPOP and DAXX completely reversed the downregulation of VEGFR2 levels. Moreover, the CUL3-SPOP-DAXX axis had the same effects on NOTCH1, DLL4 and NRP1 expression. Taken together, these findings suggest that the CUL3-SPOP-DAXX axis plays a very important role in endothelial cell function by targeting key angiogenic regulators.
authors.affiliation: Division of Cell Growth and Tumor Regulation, Proteo-Science Center (PROS), Ehime University, Toon, Ehime, Japan.|Department of Cardiovascular and Thoracic Surgery, Ehime University Graduate School of Medicine, Ehime, Japan.
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Sakaue
authors.affiliation: Department of Integrative Pathophysiology, Proteo-Science Center (PROS), Ehime University, Toon, Ehime, Japan.
authors.forename: Iori
authors.initials: I
authors.lastname: Sakakibara
authors.affiliation: Department of Biochemistry and Molecular Genetics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Uesugi
authors.affiliation: Department of Biochemistry and Molecular Genetics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Fujisaki
authors.affiliation: Department of Oral and Maxillofacial Surgery, Ehime University, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan.
authors.forename: Koh-Ichi
authors.initials: KI
authors.lastname: Nakashiro
authors.affiliation: Department of Oral and Maxillofacial Surgery, Ehime University, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hamakawa
authors.affiliation: Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Kubota
authors.affiliation: Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Joh
authors.affiliation: Department of Integrative Pathophysiology, Proteo-Science Center (PROS), Ehime University, Toon, Ehime, Japan.
authors.forename: Yuuki
authors.initials: Y
authors.lastname: Imai
authors.affiliation: Department of Cardiovascular and Thoracic Surgery, Ehime University Graduate School of Medicine, Ehime, Japan.
authors.forename: Hironori
authors.initials: H
authors.lastname: Izutani
authors.affiliation: Division of Cell Growth and Tumor Regulation, Proteo-Science Center (PROS), Ehime University, Toon, Ehime, Japan.|Department of Biochemistry and Molecular Genetics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Higashiyama
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D056970:Co-Repressor Proteins; D044842:Cullin Proteins / Q000235:genetics / Q000378:metabolism*; D003517:Cyclopentanes / Q000494:pharmacology; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D055785:Gene Knockdown Techniques; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D018832:Molecular Chaperones; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D011743:Pyrimidines / Q000494:pharmacology; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000235:genetics* / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C503645:CUL3 protein, human; D056970:Co-Repressor Proteins; D044842:Cullin Proteins; D003517:Cyclopentanes; C106985:DAXX protein, human; D018832:Molecular Chaperones; D009687:Nuclear Proteins; D011743:Pyrimidines; D012097:Repressor Proteins; C509761:SPOP protein, human; C000588866:KDR protein, human; D040301:Vascular Endothelial Growth Factor Receptor-2; C539933:pevonedistat