FIGURE 5:

Stability of lattice- and tip-loaded molecules of sfGFP-2592C in the presence of KCl. (A) Experimental setup showing the sequence of incubations to induce a mixture of lattice- and tip-binding molecules or only lattice-binding ones. Microtubules are grown in the presence (left) or absence (right) of 2 nM sfGFP-2592C and then stabilized by addition of a GMPCPP-tubulin cap. Stabilized microtubules are then incubated in the same concentration of sfGFP-2592C and washed in 100 mM KCl. The GFP signal remaining on the microtubules is then quantified. Scale bar, 5 µm. (B) Images of individual microtubules (red) grown in the presence (left) or absence of sfGFP-2592C (right) before and after KCl wash. (C) Average microtubule-associated GFP intensity for the conditions in B.