Cover Figure - Microtubule dynamics in the nascent lamellum of a living PtK1 cell. Images taken at 3 time points (0, 33 and 153 s) were digitally colorized in blue, green and red, respectively, and merged. Single colors indicate microtubule domains present only at the respective time point. Due to superposition of colors, microtubule domains present during the entire period of observation appear white (blue+green+red); domains which disappeared after second time point appear cyan (blue+green); domains which were formed after the first time point and survived till the end of observation appear yellow (green + red). Note numerous free microtubules born during the period of observation, some of which also died.