title: Integrin-mediated cell surface recruitment of autotaxin promotes persistent directional cell migration.
abstract: Autotaxin (ATX) is a secreted lysophospholipase D (lysoPLD) that binds to integrin adhesion receptors. We dissected the roles of integrin binding and lysoPLD activity in stimulation of human breast cancer and mouse aortic vascular smooth muscle cell migration by ATX. We compared effects of wild-type human ATX, catalytically inactive ATX, an integrin binding-defective ATX variant with wild-type lysoPLD activity, the isolated ATX integrin binding N-terminal domain, and a potent ATX selective lysoPLD inhibitor on cell migration using transwell and single-cell tracking assays. Stimulation of transwell migration was reduced (18 or 27% of control, respectively) but not ablated by inactivation of integrin binding or inhibition of lysoPLD activity. The N-terminal domain increased transwell migration (30% of control). ATX lysoPLD activity and integrin binding were necessary for a 3.8-fold increase in the fraction of migrating breast cancer cell step velocities >0.7 μm/min. ATX increased the persistent directionality of single-cell migration 2-fold. This effect was lysoPLD activity independent and recapitulated by the integrin binding N-terminal domain. Integrin binding enables uptake and intracellular sequestration of ATX, which redistributes to the front of migrating cells. ATX binding to integrins and lysoPLD activity therefore cooperate to promote rapid persistent directional cell migration.
authors.affiliation: 1University of Kentucky, 741 South Limestone St., Lexington KY 40536, USA. A.J.M., a.j.morris@uky.edu.
authors.forename: Tao
authors.initials: T
authors.lastname: Wu
authors.forename: Craig Vander
authors.initials: CV
authors.lastname: Kooi
authors.forename: Pritom
authors.initials: P
authors.lastname: Shah
authors.forename: Richard
authors.initials: R
authors.lastname: Charnigo
authors.forename: Cai
authors.initials: C
authors.lastname: Huang
authors.forename: Susan S
authors.initials: SS
authors.lastname: Smyth
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Morris
mesh_terms: D002448:Cell Adhesion / Q000235:genetics / Q000502:physiology; D002460:Cell Line; D002465:Cell Movement / Q000235:genetics / Q000502:physiology*; D006801:Humans; D016023:Integrins / Q000378:metabolism*; D008246:Lysophospholipids / Q000378:metabolism; D008856:Microscopy, Fluorescence; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D000099189:Lysophospholipase D
chemical_list: D016023:Integrins; D008246:Lysophospholipids; D010727:Phosphoric Diester Hydrolases; D000099189:Lysophospholipase D; C032881:lysophosphatidic acid
keywords: cell adhesion; cell motility; lysophosphatidic acid; lysophospholipase