Tetraspanin CD151 regulates α6β1 integrin adhesion strengthening
- Jan Lammerding*,†,
- Alexander R. Kazarov†,‡,
- Hayden Huang§,
- Richard T. Lee*,§, and
- Martin E. Hemler‡,¶
- *Biological Engineering Division, Massachusetts Institute of Technology, Cambridge, MA 02139; ‡Dana-Farber Cancer Institute, Room D-1430, 44 Binney Street, Boston, MA 02115; and §Cardiovascular Division, Brigham and Women's Hospital, Boston, MA 02115
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Edited by Thomas P. Stossel, Harvard Medical School, Boston, MA, and approved May 6, 2003 (received for review December 11, 2002)
Abstract
The tetraspanin CD151 molecule associates specifically with laminin-binding integrins, including α6β1. To probe strength of α6β1-dependent adhesion to laminin-1, defined forces (0–1.5 nN) were applied to magnetic laminin-coated microbeads bound to NIH 3T3 cells. For NIH 3T3 cells bearing wild-type CD151, adhesion strengthening was observed, as bead detachment became more difficult over time. In contrast, mutant CD151 (with the C-terminal region replaced) showed impaired adhesion strengthening. Static cell adhesion to laminin-1, and detachment of beads coated with fibronectin or anti-α6 antibody were all unaffected by CD151 mutation. Hence, CD151 plays a key role in selectively strengthening α6β1 integrin-mediated adhesion to laminin-1.
