Figure S1.

Supplemental data associated with Fig. 1. (A) Signal quantification of GFP (by itself, not fused to Ndc80C) and Ndc80C-GFP–coated beads. Black bars (bin size 50) represent the number of fluorescent spots with the indicated intensity. The red line is the lognormal fit of the quantification. A.U., arbitrary unit. (B) Kymograph (left) shows that the Dam1C-GFP signal tracked the end of a depolymerizing MT. Scale bars, 5 µm (horizontal) and 60 s (vertical). Graph (right) shows fold increases of Dam1C-GFP signals at the plus ends of individual MTs. The Dam1C-GFP signal for the first 1 µm after their appearance was averaged and set to one for normalization. The Dam1C signal during subsequent MT shrinkage was averaged in 1-µm increments, normalized, and plotted against the length of MT shrinkage. # shows the fold increase of the example shown in the kymograph (left). (C) Images show a representative example of dynamic MTs when they were incubated with Ndc80C-GFP–coated nanobeads (left) or control nanobeads without Ndc80C-GFP (right). The yellow arrowhead indicates an Ndc80C-GFP–coated nanobead on the lateral side of a dynamic MT. Scale bar, 5 µm. Graph shows the number of nanobeads (with and without Ndc80C-GFP coating) on dynamic MTs per millimeter length of MTs. (D) Graph shows MT depolymerization rates either in the absence or presence of Dam1C in solution and in the absence or presence of Ndc80C nanobead at the end of depolymerizing MT (n = 54, 38, 32, and 44 from left to right). Error bars represent standard deviation. The MT depolymerization rates determined from the kymographs as shown on the right. Scale bars, 5 µm (horizontal) and 60 s (vertical). **** P < 0.0001; ns, not significant (P = 0.73).