Critical role of integrin alpha 5 beta 1 in urokinase (uPA)/urokinase receptor (uPAR, CD87) signaling

Urokinase-type plasminogen activator (uPA) induces cell adhesion and chemotactic movement. uPA signaling requires its binding to uPA receptor (uPAR/CD87), but how glycosylphosphatidylinositol-anchored uPAR mediates signaling is unclear. uPAR is a ligand for several integrins (e.g. alpha 5 beta 1) and supports cell-cell interaction by binding to integrins on apposing cells (in trans). We studied whether binding of uPAR to alpha 5 beta 1 in cis is involved in adhesion and migration of Chinese hamster ovary cells in response to immobilized uPA. This process was temperature-sensitive and required mitogen-activated protein kinase activation. Anti-uPAR antibody or depletion of uPAR blocked, whereas overexpression of uPAR enhanced, cell adhesion to uPA. Adhesion to uPA was also blocked by deletion of the growth factor domain (GFD) of uPA and by anti-GFD antibody, whereas neither the isolated uPA kringle nor serine protease domain supported adhesion directly. Interestingly, anti-alpha 5 antibody, RGD peptide, and function-blocking mutations in alpha 5 beta 1 blocked adhesion to uPA. uPA-induced cell migration also required GFD, uPAR, and alpha 5 beta 1, but alpha 5 beta 1 alone did not support uPA-induced adhesion and migration. Thus, binding of uPA causes uPAR to act as a ligand for alpha 5 beta 1 to induce cell adhesion, intracellular signaling, and cell migration. We demonstrated that uPA induced RGD-dependent binding of uPAR to alpha 5 beta 1 in solution. These results suggest that uPA-induced adhesion and migration of Chinese hamster ovary cells occurs as a consequence of (a) uPA binding to uPAR through GFD, (b) the subsequent binding of a uPA.uPAR complex to alpha 5 beta 1 via uPAR, and (c) signal transduction through alpha 5 beta 1.

Medienart:

Artikel

Erscheinungsjahr:

2003

Erschienen:

2003

Enthalten in:

Zur Gesamtaufnahme - volume:278

Enthalten in:

The Journal of biological chemistry - 278(2003), 32 vom: 08. Aug., Seite 29863-72

Sprache:

Englisch

Beteiligte Personen:

Tarui, Takehiko [VerfasserIn]
Andronicos, Nicholas [VerfasserIn]
Czekay, Ralf-Peter [VerfasserIn]
Mazar, Andrew P [VerfasserIn]
Bdeir, Khalil [VerfasserIn]
Parry, Graham C [VerfasserIn]
Kuo, Alice [VerfasserIn]
Loskutoff, David J [VerfasserIn]
Cines, Douglas B [VerfasserIn]
Takada, Yoshikazu [VerfasserIn]

Themen:

78VO7F77PN
Antibodies, Monoclonal
Arginyl-glycyl-aspartic acid
DNA, Complementary
EC 3.4.21.73
Enzyme Inhibitors
Fibronectins
Glycosylphosphatidylinositols
Integrin alpha5beta1
Journal Article
Ligands
Oligopeptides
Receptors, Cell Surface
Receptors, Urokinase Plasminogen Activator
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
Urokinase-Type Plasminogen Activator

Anmerkungen:

Date Completed 24.09.2003

Date Revised 09.02.2021

published: Print-Electronic

Citation Status MEDLINE

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM125217560