Figure 5. Screenshots of cell division videos support the notion that G-1 targets microtubules to suppress cell growth.

Hela cells with GFP labelled α-tubulin were incubated in the culture chamber. Cell division and microtubule dynamics were monitored with a high-resolution laser scanning microscope and a live cell imaging system. A) Screenshots from the time-lapse video showing the dynamics of microtubules in cells treated with vehicle (0.1% DMSO, top panel) or G-1 (lower panel). White arrows point to the intact and depolymerized microtubules. B) Representative screenshots from time-lapse videos showing the microtubule dynamics and morphology cells with or without G-1 treatment. Red arrows indicate the time point when DMSO or G-1 was added to the culture system. This video clearly shows that G-1 treatment interrupts microtubule assembly, leading to the failure of spindle formation and subsequent activation of cell death pathways, which is indicated by the formation of apoptotic bodies.