text_1: Pretreatment with the Arp2/3 inhibitor CK-666 affects lamelliopodia formation.
text_2: Using light and electron microscopy, we demonstrate that Arp2/3 complex inhibition via the drug CK666 dramatically altered LP actin architecture, slowed centripetal flow, drove a lamellipodial-to-filopodial shape change in suspended cells, and induced a novel actin structural organization during cell spreading.