TPA primes alpha2beta1 integrins for cell adhesion.
Integrin avidity is regulated by changes in the conformation of the heterodimer and cluster formation. We measured cell adhesion by integrin alpha2beta1 (CHO-alpha2) to collagen at short contact times (0.5-60s) by single cell force spectroscopy (SCFS). The adhesion increased rapidly with contact time and was further strengthened by the addition of 12-O-tetradecanoylphorbol-13-acetate (TPA), a protein kinase C (PKC) and integrin activator. TPA also improved the strength of adhesive units. Furthermore, changes in membrane nanotube properties indicated better coupling of integrins to the cell cytoskeleton. We conclude that in addition to increasing integrin avidity TPA strengthens integrin-cytoskeletal linkage.
Tulla
Mira
M
Biotechnology Center, University of Technology Dresden, Germany. mira.tulla@biotec.tu-dresden.de
Helenius
Jonne
J
Jokinen
Johanna
J
Taubenberger
Anna
A
Müller
Daniel J
DJ
Heino
Jyrki
J
D000818:Animals; D016466:CHO Cells; D002448:Cell Adhesion / Q000187:drug effects; D003094:Collagen / Q000737:chemistry; D006224:Cricetinae; D003412:Cricetulus; D006801:Humans; D038982:Integrin alpha2beta1 / Q000819:agonists / Q000235:genetics / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D043942:Nanotubes / Q000737:chemistry; D011493:Protein Kinase C / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014162:Transfection
D038982:Integrin alpha2beta1; D003094:Collagen; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate