| First Author | Rullo J | Year | 2012 |
| Journal | J Cell Biol | Volume | 197 |
| Issue | 1 | Pages | 115-29 |
| PubMed ID | 22472442 | Mgi Jnum | J:185044 |
| Mgi Id | MGI:5427279 | Doi | 10.1083/jcb.201107140 |
| Citation | Rullo J, et al. (2012) Actin polymerization stabilizes alpha4beta1 integrin anchors that mediate monocyte adhesion. J Cell Biol 197(1):115-29 |
| abstractText | Leukocytes arrested on inflamed endothelium via integrins are subjected to force imparted by flowing blood. How leukocytes respond to this force and resist detachment is poorly understood. Live-cell imaging with Lifeact-transfected U937 cells revealed that force triggers actin polymerization at upstream alpha4beta1 integrin adhesion sites and the adjacent cortical cytoskeleton. Scanning electron microscopy revealed that this culminates in the formation of structures that anchor monocyte adhesion. Inhibition of actin polymerization resulted in cell deformation, displacement, and detachment. Transfection of dominant-negative constructs and inhibition of function or expression revealed key signaling steps required for upstream actin polymerization and adhesion stabilization. These included activation of Rap1, phosphoinositide 3-kinase gamma isoform, and Rac but not Cdc42. Thus, rapid signaling and structural adaptations enable leukocytes to stabilize adhesion and resist detachment forces. |
