Death-associated protein kinase 2 (DAPK2) is a positive regulator of apoptosis. Although we recently reported that 14-3-3 proteins inhibit DAPK2 activity and its subsequent apoptotic effects via binding to DAPK2, the molecular mechanisms underlying the DAPK2-mediated apoptotic pathway remain unclear. Therefore, we attempted to further identify DAPK2-interacting proteins using pull-down assays and mass spectrometry. The microtubule beta-tubulin was identified as a novel DAPK2-binding protein in HeLa cells. Pull-down assays revealed that DAPK2 interacted with the alpha/beta-tubulin heterodimer, and that the C-terminal region of DAPK2, which differs from that of other DAPK family members, was sufficient for the association with beta-tubulin. Although the microtubule-depolymerizing agent nocodazole induced apoptosis in HeLa cells, the level of apoptosis was significantly decreased in the DAPK2 knockdown cells. Furthermore, we found that treatment with nocodazole resulted in an increased binding of DAPK2 to beta-tubulin. These findings indicate that DAPK2 mediates nocodazole-induced apoptosis via binding to tubulin. (C) 2015 Elsevier Inc. All rights reserved.