Coupling with myosin in the lamella. (A) Withdrawal and integration of a filopodium into actomyosin network of lamella. Cell was transfected with mCherry-actin and EGFP-myosin regulatory light chain. Arrows indicate a filopodium that first became kinked and was then drawn into the lamella with the progressive accumulation of myosin and the eventual transition into a stress fiber bundle. Times are given in minutes and seconds. See Video 6 . (B) Inhibition of myosin contractility with 50 μM blebbistatin. CAR fibroblast transfected with mCherry-actin. Filopodia formation was not inhibited and filopodia translocated into the lamella (arrowheads) but did not form contractile bundles. See Video 7.