Wiskostatin is a potent and selective inhibitor of neuronal Wiskott-Aldrich syndrome protein ( N-WASP )-mediated actin polymerization by stabilization of the closed, autoinhibited conformation, thereby preventing Arp2/3 complex activation. Wiskostatin is also a dynamin inhibitor with an IC 50 value of 20.7 μM and a potent inhibitor of clathrin-mediated endocytosis with an IC 50 value of 6.9 μM. Wiskostatin causes a rapid, profound, and irreversible decrease in cellular ATP levels. Wiskostatin also induces disassembly of podosomes in a murine monocyte cell line.