Cell adhesion can result in dramatic changes in cell motility, growth, and differentiation. These functional responses are often initiated by integrins, the very molecules that tether some cells. Integrin signaling modulates cell physiology by a number of mechanisms, including the regulation of transcription. The strength of these transcription-based effects, however, has made it difficult to determine if gene expression is controlled by other pathways. In this issue, Pabla et al. (page ) use activated platelets, a cell type without nuclei, to examine how integrin engagement affects protein expression in the absence of transcription. The results show that outside-in signaling by integrins controls protein production at the level of trans- lation.
In a previous study, these authors made the surprising finding that platelets undergo new protein synthesis upon activation, despite their lack of nuclei. Now Pabla et al. show that engagement of the platelet integrin αIIbβ3 by...
