Weak and tunable adhesion-clutch drives rapid cell migration and glioblastoma motility

To move forward, migrating cells must exert backward forces against the extracellular environment. Recent studies have highlighted the importance of integrin-independent forces for cell migration; but the molecular machinery that exerts forces remains unclear. Here, we show that the clutch-linker molecule shootin1 and the cell adhesion molecule L1 transmit the backward force of treadmilling actin filaments to the adhesive environment for rapid dendritic cell migration. Notably, shootin1 and L1 transmit weak traction forces, ∼100 times weaker than integrin-based forces, by constituting an integrin-independent slippery adhesion-clutch. This adhesion-clutch system is tunable in response to the chemoattractant CCL19 and the adhesive ligand laminin and mediates chemotaxis through its polarized activation within cells. Furthermore, its aberrant activity enhances glioblastoma cell motility. Our results show that the weak adhesion-clutch is well-suited for rapid cell migration, without forming strong adhesions that impede cell motility, and provides a potential target for inhibiting abnormal cell motility.