Figure 8.

Knockdown or inhibition of Preso reduces F-actin levels in dendritic spines. A, Preso shRNA knockdown or overexpression of a dominant-negative Preso (ΔWW+PDZ+C) in neurons reduces spine levels of F-actin but not that of PSD-95. Cultured neurons were transfected with a Preso knockdown construct (sh-Preso), an empty pSuper vector (sh-vec), or a Preso mutant construct (sh-vec+ΔWW+PDZ+C; DIV 9–16) and stained for EGFP, F-actin (by rhodamine–phalloidin), and PSD-95. Spine levels represent average fluorescence intensities of F-actin or PSD-95 signals in a spine. Scale bar, 5 μm. B, Quantification of the results from A. Mean ± SEM (n = 29 for sh-vec, 21 for sh-Preso, and 27 for ΔWW+PDZ+C; ***p < 0.001, ANOVA Tukey's test).