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NASA NTRS · 20040087635

Tetraspanin CD151 regulates alpha6beta1 integrin adhesion strengthening

Lammerding, Jan·Kazarov, Alexander R.·Huang, Hayden·Lee, Richard T.·Hemler, Martin E.
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Abstract

The tetraspanin CD151 molecule associates specifically with laminin-binding integrins, including alpha6beta1. To probe strength of alpha6beta1-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-alpha6 antibody were all unaffected by CD151 mutation. Hence, CD151 plays a key role in selectively strengthening alpha6beta1 integrin-mediated adhesion to laminin-1.

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NASA Discipline Cell BiologyNon-NASA CenterIntegrin alpha6beta1/metabolismLaminin/metabolismAntigens, CD/chemistry/genetics/physiologyAnimalsTime FactorsProtein Structure, TertiaryMagneticsSupport, U.S. Gov't, Non-P.H.SMutationMiceStress, MechanicalSupport, U.S. Gov't, P.H.SProtein Binding3T3 CellsCell AdhesionTemperatureCalibrationCell Line

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Lammerding, Jan, Kazarov, Alexander R., Huang, Hayden, Lee, Richard T., Hemler, Martin E.. 2003-06-24. Tetraspanin CD151 regulates alpha6beta1 integrin adhesion strengthening. https://ntrs.nasa.gov/citations/20040087635

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