Live-cell magnetic manipulation of recycling endosomes reveals their direct effect on actin protrusions to promote invasive migration.

Endocytic recycling pathways play key roles in a broad range of cellular processes, and many vesicle trafficking regulators are implicated in progression of disease such as cancer. The Rab11 family (Rab11a, Rab11b, and Rab25) controls the return of internalized cargos to the plasma membrane, and Rab25 has been implicated in the aggressiveness of cancer by promoting invasive migration. However, while Rab25 vesicles distribute to the leading edge of moving cells, how directly they contribute to cell protrusion is not clear. Here, we adopt a magnetogenetic approach that allows direct manipulation of Rab25 positioning to show that localization to the cell periphery drives the formation of F-actin protrusions. We demonstrate that endogenous Rab25 vesicles coordinate the positioning of key cargos, including the actin regulator FMNL1 and integrin β1, with the activation of Rho guanosine triphosphatases at the plasma membrane to generate and maintain F-actin-rich filopodium-like protrusions and promote cancer cell invasive migration in the three-dimensional matrix.