Time lapse recording showing the development of neuron polarity in a hippocampal neuron growing in vitro. This recording captures not only the formation of the axon (the longest process, oriented down...

This is Video S1 and it corresponds to Figure 2A. It shows that local blebbistatin micropipetting, but not DMSO, increases spine formation and extension (arrowheads). Equal volumes of blebbistatin and...

This is Video S2 which corresponds to still images in top row of Figure 2D. It shows the spine dynamics of control neurons. Time-lapse confocal imaging was performed on DIV14 hippocampal neurons co-ex...

This is Video S3,which corresponds to still images in bottom row of Fig. 2D. It shows that knocking down levels of Myosin II B (MIIB) increases spine dynamics. Spines from MIIB knockdown neurons exten...

Cultured hippocampal neurons after 23 days in vitro, immunostained for MAP2, a microtubule associated protein localized to dendrites (red), and PSD95, a scaffolding protein concentrated in the postsyn...

Cultured hippocampal neurons after 23 days in vitro, immunostained for MAP2, a microtubule associated protein localized to dendrites (red), and PSD95, a scaffolding protein concentrated in the postsyn...

Cultured hippocampal neurons after 23 days in vitro, immunostained for MAP2, a microtubule associated protein localized to dendrites (red), and PSD95, a scaffolding protein concentrated in the postsyn...

Cultured hippocampal neurons after 23 days in vitro, immunostained for MAP2, a microtubule associated protein localized to dendrites (red), and PSD95, a scaffolding protein concentrated in the postsyn...

Development of the axon and dendritic arbors in cultured hippocampal neurons after 2 days in vitro. MAP2 staining (red) highlights the dendrites, while microtubule staining (green) reveals both the ax...

Development of the axon and dendritic arbors in cultured hippocampal neurons after 3 days in vitro. MAP2 staining (red) highlights the dendrites, while microtubule staining (green) reveals both the ax...