The mitogen-activated protein kinase p38 plays key roles in cell progression, differentiation, inflammation, and apoptosis, p38 is activated by a variety of extracellular stimuli such as UV and proinflammatory cytokine tumor necrosis factor alpha (TNF-).It has been suggested that the microtubule might be essential for the activation of p38 pathway.However, several other groups have reported that microtubule-interfering agents stimulate the activation of MAPK superfamily members including p38 in certain cell context.In this work, we report that nocodazole antagonized UV-or TNF--induced p38 activation, even though this drug by itself weakly activated p38.