Figure 9.

Cytochalasin D disruption of F-actin causes CaMKII clusters to disperse. A, CaMKIIα.FingR-GFP-labeled clusters in cell body of a cortical neuron in culture. B, Addition of cytochalasin D (2 μm) for 98 min results in dispersal of the clusters in A. C, Phalloidin staining of cell in B and C verifies that addition of cytochalasin D mediated dispersal of actin clusters. D–F, Clusters in a cortical pyramidal neuron labeled with CaMKIIα.FingR-GFP (D) are not dispersed by DMSO (E), which also leaves clusters of actin filaments intact (F). G, I_{cluster/background} at t = 0 s and t = 21.5 s for CaMKIIα.FingR-GFP following addition of either cytochalasin D or DMSO. Scale bars, 10 μm.