title: The cytoplasmic adaptor protein X11alpha and extracellular matrix protein Reelin regulate ApoE receptor 2 trafficking and cell movement.
abstract: The goal of this study was to determine the effect of X11alpha on ApoE receptor 2 (ApoEr2) trafficking and the functional significance of this interaction on cell movement in MCF 10A epithelial cells. We found that X11alpha increased surface levels of ApoEr2 by 64% compared to vector control, as determined by surface protein biotinylation. To examine the functional significance of this effect, we tested whether ApoEr2 played a novel role in cell movement in a wound-healing assay. We found that overexpression of ApoEr2 in MCF 10A cells increased cell migration velocity by 87% (P<0.01, n=4) compared to GFP control. Cotransfection of X11alpha had an additive effect on average velocity compared to ApoEr2 alone (13%; P<0.05, n=4). In addition, we tested whether ApoEr2 ligands altered the effect of ApoEr2 on cell movement. We found that treatment with concentrated medium containing the extracellular matrix protein Reelin, but not control medium, further increased the velocity of ApoEr2- but not APP-transfected cells (20%; P<0.001, n=4). Similarly, Reelin treatment increased cell velocity in the presence of ApoEr2 and X11alpha (10%; P<0.05, n=4). In the present study, we are the first to demonstrate that ApoEr2 regulates cell movement, and both X11alpha and Reelin enhance this effect.
authors.affiliation: Department of Neurology, Georgetown University, 4000 Reservoir Road NW, Washington, DC 20057, USA.
authors.forename: S Sakura
authors.initials: SS
authors.lastname: Minami
authors.forename: You Me
authors.initials: YM
authors.lastname: Sung
authors.forename: Sonya B
authors.initials: SB
authors.lastname: Dumanis
authors.forename: Seong Hwan
authors.initials: SH
authors.lastname: Chi
authors.forename: Mark P
authors.initials: MP
authors.lastname: Burns
authors.forename: Eun-Jung
authors.initials: EJ
authors.lastname: Ann
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Suzuki
authors.forename: R Scott
authors.initials: RS
authors.lastname: Turner
authors.forename: Hee-Sae
authors.initials: HS
authors.lastname: Park
authors.forename: Daniel T S
authors.initials: DT
authors.lastname: Pak
authors.forename: G William
authors.initials: GW
authors.lastname: Rebeck
authors.forename: Hyang-Sook
authors.initials: HS
authors.lastname: Hoe
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D001693:Biological Transport, Active; D019556:COS Cells; D015820:Cadherins; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002465:Cell Movement / Q000502:physiology*; D002522:Chlorocebus aethiops; D005091:Exons; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D026502:LDL-Receptor Related Proteins; D009419:Nerve Tissue Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D054731:PDZ Domains; D010766:Phosphorylation; D051076:Proto-Oncogene Proteins c-fyn / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D051381:Rats; D018110:Receptors, Lipoprotein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000091042:Reelin Protein; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D020798:Two-Hybrid System Techniques; D014945:Wound Healing / Q000502:physiology
chemical_list: C079091:APBA1 protein, human; C491636:APBA2 protein, human; D048868:Adaptor Proteins, Signal Transducing; D015820:Cadherins; D002352:Carrier Proteins; D015816:Cell Adhesion Molecules, Neuronal; D016326:Extracellular Matrix Proteins; D026502:LDL-Receptor Related Proteins; D009419:Nerve Tissue Proteins; D034741:RNA, Small Interfering; D018110:Receptors, Lipoprotein; D011994:Recombinant Proteins; D000091042:Reelin Protein; C000717129:Reln protein, rat; C098773:low density lipoprotein receptor-related protein 8; C494957:FYN protein, human; D051076:Proto-Oncogene Proteins c-fyn; C000717127:RELN protein, human; D012697:Serine Endopeptidases