Figure 4.

Antagonism of cdk5 inhibits uptake of FM1–43, but not FM2–10. A, Cultures were loaded and unloaded with FM1–43 using the same protocol as in Figure 1A. Where indicated, cultures were preincubated with 50 μm roscovitine (Rosco) for 10 min before and during S2 loading. B, Cumulative histogram of the effect of roscovitine on FM1–43 loading in individual nerve terminals (ΔS2/ΔS1, n = 258, Ctrl; n = 270, Rosco). Closed symbols, Control (Ctrl); gray symbols, roscovitine. C, Cultures were loaded and unloaded with either FM2–10 and FM1–43 using an identical protocol to Figure 1A except that cultures were preincubated with 50 μm roscovitine for 10 min before and during all steps before and including S2 loading. D, Cumulative histogram of the effect of roscovitine on dye loading in individual nerve terminals (ΔS2/ΔS1, n = 209, FM2–10; n = 337, FM1–43). Open symbols represent FM2–10 uptake whereas closed symbols represent FM1–43 uptake both in roscovitine-treated cultures. For all experiments, n = 3, apart from n = 4 for FM1–43 data in D.