Platinum replica depicting the cytoskeletal organization of dendritic spines in extracted 14 DIV neurons. Mushroom spines associate with dendrites at the base (bottom) and with axons by the head (top). Unlabeled insets show the smaller versions of the corresponding main panels with axons color-coded in purple, dendrites in yellow, and spines in cyan. Thick fibers in neurites represent microtubules. Red asterisks indicate putative PSD fragments. Yellow boxes are enlarged in panels with corresponding numbers. Box 1, interaction of putative PSD (arrow) from the spine head with axonal intermediate filaments (green); actin filaments are shown in cyan and a microtubule in red. Boxes 2 and 3, branched actin filaments (cyan) in the head (2) and at the neck–head junction (3). Insets in panels 2 and 3 show nonpseudocolored regions outlined by yellow boxes. Dashed arrows in panel 3 indicate potential filament breakage. Bars, 0.2 μm. Image corresponds to Figure 2a in Mol Biol Cell. 2010 Jan 1;21(1):165-76. The entire panel (this image) is available as CIL 40660. The uncolorized image is available as CIL 40659. Box 1, 2, and 3 are CIL 40661, 40662, and 40663, respectively.