title: Plasma membrane Pdia3 and VDR interact to elicit rapid responses to 1α,25(OH)(2)D(3).
abstract: 1α,25-Dihydroxyvitamin D3 (1α,25(OH)2D3) regulates osteoblasts through genomic and rapid membrane-mediated responses. Here we examined the interaction of protein disulfide isomerase family A, member 3 (Pdia3) and the traditional vitamin D receptor (VDR) in plasma membrane-associated responses to 1α,25(OH)2D3. We found that Pdia3 co-localized with VDR and the caveolae scaffolding protein, caveolin-1 on the surface of MC3T3-E1 osteoblasts. Immunoprecipitation showed that both Pdia3 and VDR interacted with caveolin-1. Pdia3 further interacted with phospholipase A2 activating protein (PLAA), whereas VDR interacted with c-Src. 1α,25(OH)2D3 changed the interactions and transport of the two receptors and rapidly activated phospholipase A2 (PLA2) and c-Src. Silencing either receptor or caveolin-1 inhibited both PLA2 and c-Src, indicating that the two receptors function interdependently. These two receptor dependent rapid responses to 1α,25(OH)2D3 regulated gene expression, proliferation and apoptosis of MC3T3-E1 cells. These data demonstrate the importance of both receptors and caveolin-1 in mediating membrane responses to 1α,25(OH)2D3 and subsequently regulating osteoblast biology.
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Jiaxuan
authors.initials: J
authors.lastname: Chen
authors.forename: Maryam
authors.initials: M
authors.lastname: Doroudi
authors.forename: Jeffery
authors.initials: J
authors.lastname: Cheung
authors.forename: Ashley L
authors.initials: AL
authors.lastname: Grozier
authors.forename: Zvi
authors.initials: Z
authors.lastname: Schwartz
authors.forename: Barbara D
authors.initials: BD
authors.lastname: Boyan
mesh_terms: D016475:3T3 Cells; D000818:Animals; D000081247:CSK Tyrosine-Protein Kinase; D051242:Caveolin 1 / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D051379:Mice; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D019704:Protein Disulfide-Isomerases / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism; D018167:Receptors, Calcitriol / Q000378:metabolism*; D015398:Signal Transduction; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000378:metabolism; D019061:src-Family Kinases / Q000378:metabolism
chemical_list: D051242:Caveolin 1; D011506:Proteins; D018167:Receptors, Calcitriol; C118756:dihydroxy-vitamin D3; C055324:phospholipase A2-activating protein; D014807:Vitamin D; D000081247:CSK Tyrosine-Protein Kinase; D019061:src-Family Kinases; C513195:Pdia3 protein, mouse; D019704:Protein Disulfide-Isomerases
keywords: 1α,25(OH)(2)D(3); 1α,25-dihydroxyvitamin D3; Alpl; Caveolin-1; MC3T3-E1 cells; PGE2; PI3K; PLA2; PLA2 activating protein; PLAA; Pdia3; Rapid responses; STSP; Spp1; VDR; alkaline phosphatase mRNA; osteopontin mRNA; phosphatidylinositol 3-kinases; phospholipase A2; prostaglandin E2; protein disulfide isomerase family A, member 3; staurosporine; vitamin D receptor