title: Suppression of Slit2/Robo1 mediated HUVEC migration by Robo4.
abstract: Slit proteins and their receptors, the Roundabout (Robo) family, are known to have a pivotal role in the vascular system. Slit2/Robo1 regulates the migration of human umbilical vein endothelial cells (HUVECs) and tumor-associated endothelial cells. Robo4, the endothelial-specific Robo, is also considered to be involved in vascular cell migration. However, the Slit/Robo signaling pathway is still unclear. Using a Boyden chamber assay, we found that Slit2 induces the migration of HUVECs under a Robo4 knockdown condition. This effect disappeared in Robo1 knockdown cells. The co-existence of the N-terminal extracellular portion of Robo1 blocked the Slit2-evoked migration of HUVECs, while that of Robo4 caused no effect. These results show that the Slit2 signal is transduced through Robo1, while the negative regulation of Robo4 is an intracellular event. Targeted proteomics using an anti-Robo1 monoclonal antibody identified CdGAP, an adhesion-localized Rac1-and Cdc42-specific GTPase activating protein, as a candidate for Slit2/Robo1 signaling. Robo1 and CdGAP were co-immunoprecipitated from CHO cells co-transfected with Robo1 and CdGAP genes. These results suggest that Slit2/Robo1 binding exerts an effect on cell migration, which is negatively regulated by Robo4, and Robo1 may function by interacting with CdGAP in HUVECs.
authors.affiliation: Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Enomoto
authors.affiliation: Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Mitsui
authors.affiliation: Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan; Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kawamura
authors.affiliation: Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Iwanari
authors.affiliation: Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Daigo
authors.affiliation: Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Horiuchi
authors.affiliation: Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Minami
authors.affiliation: Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Kodama
authors.affiliation: Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan. Electronic address: hamakubo@qbm.rcast.u-tokyo.ac.jp.
authors.forename: Takao
authors.initials: T
authors.lastname: Hamakubo
mesh_terms: D002460:Cell Line; D002465:Cell Movement / Q000502:physiology*; D042783:Endothelial Cells / Q000166:cytology / Q000502:physiology*; D020690:GTPase-Activating Proteins / Q000378:metabolism*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D000097905:Roundabout Proteins; D000098552:Slit Homolog 2 Protein
chemical_list: D020690:GTPase-Activating Proteins; D036341:Intercellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D010750:Phosphoproteins; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic; D000097905:Roundabout Proteins; D000098552:Slit Homolog 2 Protein; C514543:ARHGAP31 protein, human; C462951:ROBO4 protein, human
keywords: CdGAP; HUVEC; Migration; Robo1; Robo4; Slit2