ABSTRACT
Integrins transmit information in both directions across the plasma membrane. Integrin affinity for ligands can be modulated by intracellular signals. Integrin ligand-binding can modify cell shape, growth, survival, and gene expression. The dynamic regulation of integrin adhesion by inside-out signaling is a crucial aspect of integrin function that is important in hemostasis, leukocyte extravasation, cell migration, and fibronectin matrix assembly. H-Ras mediated integrin suppression correlates with the activation of ERK MAP kinase and does not require mRNA transcription or protein synthesis. The inhibition of integrin signaling is structurally specific as chimeric molecules with either integrin α cytoplasmic domains or certain β cytoplasmic domain point mutants lack inhibitory activity.
