Table 1.
Phosphocellulose purified bovine brain microtubules were assembled to steady state in the presence of taccalonolide AJ, paclitaxel or vehicle and the dynamic instability parameters were determined
| |
Vehicle |
1 μM AJ |
3 μM AJ |
250 nM PTX |
|||
|---|---|---|---|---|---|---|---|
| Value ± SEM | Value ± SEM | % Change | Value ± SEM | % Change | Value ± SEM | % Change | |
| Growth rate (μm/min) |
2.7 ± 0.2 |
3.1 ± 0.2 |
+15 |
3 ± 0.3 |
+11 |
2.8 ± 0.2 |
+4 |
| Shortening rate (μm/min) |
11.9 ± 1 |
7.4 ± 0.6** |
−38 |
4 ± 0.5*** |
−66 |
5.8 ± 0.4*** |
−51 |
| Percent time growing |
56 |
34 |
−39 |
26 |
−54 |
26 |
−54 |
| Percent time shortening |
19 |
15 |
−21 |
12 |
−37 |
22 |
+16 |
| Percent time attenuated |
25 |
51 |
+104 |
62 |
+148 |
52 |
+108 |
| Catastrophe frequency (per min) |
0.28 ± 0.05 |
0.21 ± 0.04* |
−25 |
0.13 ± 0.03*** |
−54 |
0.26 ± 0.04 |
−7 |
| Rescue frequency (per min) |
0.84 ± 0.17 |
0.60 ± 0.15 |
−29 |
0.47 ± 0.15* |
−44 |
0.30 ± 0.09** |
−64 |
| Dynamicity (μm/min) | 2.73 | 1.74 | −36 | 0.95 | −65 | 1.63 | −40 |
Approximately 25 microtubules were measured for each condition.
*P<0.05; **P < 0.01; ***P < 0.001, as determined with a Student’s t-test.