title: ASIC proteins regulate smooth muscle cell migration.
abstract: The purpose of the present study was to investigate Acid Sensing Ion Channel (ASIC) protein expression and importance in cellular migration. We recently demonstrated that Epithelial Na(+)Channel (ENaC) proteins are required for vascular smooth muscle cell (VSMC) migration; however, the role of the closely related ASIC proteins has not been addressed. We used RT-PCR and immunolabeling to determine expression of ASIC1, ASIC2, ASIC3 and ASIC4 in A10 cells. We used small interference RNA to silence individual ASIC expression and determine the importance of ASIC proteins in wound healing and chemotaxis (PDGF-bb)-initiated migration. We found ASIC1, ASIC2, and ASIC3, but not ASIC4, expression in A10 cells. ASIC1, ASIC2, and ASIC3 siRNA molecules significantly suppressed expression of their respective proteins compared to non-targeting siRNA (RISC) transfected controls by 63%, 44%, and 55%, respectively. Wound healing was inhibited by 10, 20, and 26% compared to RISC controls following suppression of ASIC1, ASIC2, and ASIC3, respectively. Chemotactic migration was inhibited by 30% and 45%, respectively, following suppression of ASIC1 and ASIC3. ASIC2 suppression produced a small, but significant, increase in chemotactic migration (4%). Our data indicate that ASIC expression is required for normal migration and may suggest a novel role for ASIC proteins in cellular migration.
authors.affiliation: Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS 39216, USA.
authors.forename: Samira C
authors.initials: SC
authors.lastname: Grifoni
authors.forename: Nikki L
authors.initials: NL
authors.lastname: Jernigan
authors.forename: Gina
authors.initials: G
authors.lastname: Hamilton
authors.forename: Heather A
authors.initials: HA
authors.lastname: Drummond
mesh_terms: D062565:Acid Sensing Ion Channels; D000818:Animals; D000077214:Becaplermin; D002448:Cell Adhesion; D002460:Cell Line; D002465:Cell Movement; D002633:Chemotaxis; D062626:Degenerin Sodium Channels; D053503:Epithelial Sodium Channels / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D020033:Protein Isoforms / Q000378:metabolism; D020574:Proto-Oncogene Proteins c-sis; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D051381:Rats; D015222:Sodium Channels / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D014945:Wound Healing
chemical_list: C568269:ASIC3 protein, rat; D062565:Acid Sensing Ion Channels; C568268:Asic1 protein, rat; C568425:Asic2 protein, rat; D062626:Degenerin Sodium Channels; D053503:Epithelial Sodium Channels; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D010982:Platelet-Derived Growth Factor; D020033:Protein Isoforms; D020574:Proto-Oncogene Proteins c-sis; D034741:RNA, Small Interfering; D015222:Sodium Channels; D000077214:Becaplermin