FIGURE 2:

Laterally associated γ-tubulin arrays and XMAP215 are classically defined nucleators. (A) Representative results of a turbidity assay for tubulin assembly at 15 μM free αβ-tubulin, with γ-tubulin added at 300 nM. The red dashed line represents 10% of the maximum light scattering. The inset shows the same data from the red box plotted on a larger scale with the data plotted as points connected by lines for clarity. The raw data from all replicates are given in Supplemental Figure 1. (B) Representative results of turbidity assay for tubulin assembly for 20, 40, or 60 nM XMAP215 with 15 μM free tubulin. XMAP215 promotes spontaneous tubulin assembly in a concentration-dependent manner. The red dashed line represents 10% of the normalized maximum light scattering. The inset shows the same data from the red box plotted on a larger scale with the data plotted as points connected by lines for clarity. SDS–PAGE of XMAP215 and the raw data for all replicates of the turbidity assay are given in Supplemental Figure 2.