Kindlin-1 binds to integrins and regulates integrin activation at cell adhesions. Here we report a new function of Kindlin-1 in regulating spindle assembly. We show that Kindlin-1 localizes to centrosomes, its concentration peaking during G2/M, where it associates with various pericentriolar material proteins, including Polo-like kinase 1. Short interfering RNA-mediated depletion of Kindlin-1 increases formation of abnormal mitotic spindles and decreases cellular survival. This effect is dependent not only on the ability of Kindlin-1 to bind integrins but also on Polo-like kinase 1-mediated Kindlin-1 phosphorylation. We demonstrate that a subcellular pool of phosphorylated Kindlin-1 is located exclusively at centrosomes. Our work identifies a novel cellular role for Kindlin-1 in ensuring mitotic spindle assembly and cellular survival that is controlled by phosphorylation via Polo-like kinase 1.
Patel, H., Zich, J., Serrels, B., Rickman, C., Hardwick, K. G., Frame, M. C., & Brunton, V. G. (2013). Kindlin-1 regulates mitotic spindle formation by interacting with integrins and Plk-1. Nature Communications, 4(n/a), 2056. https://doi.org/10.1038/ncomms3056