Fig. 3.

Disorazole C₁ disrupts microtubules in vivo. Microtubules in A549 cells were partially disrupted after disorazole treatment at 2 nM for 24 h (b) and more completely at 72 h (c) compared with DMSO vehicle control (a). The disruption was similar to that seen with 2 nM vinblastine treatment at 24 h (d) and 72 h (e). A concentration response effect on microtubules after a 1-h treatment was observed with 2 nM (f), 10 nM (g), and 20 nM (h) disorazole C₁, similar to 20 nM vinblastine (i). With both compounds, apparent tubulin aggregation was observed at higher concentrations (h and i). Cells were fixed and stained with anti-α-tubulin antibody to visualize microtubules (green) and 4,6-diamidino-2-phenylindole to visualize nuclei (blue).