Page "Synapsin" Paragraph 2

Gene knockout studies in mice ( where the mouse is unable to produce synapsin ) have had some surprising results.

Mice lacking all three synapsins are prone to seizures, and experience learning defects.

These results suggest that while synapsins are not essential for synaptic function, they do serve an important modulatory role.

Conversely, studies using transgenic mice in which neuronal signaling is abolished in specific circuitries showed that synaptic activity regulates, but is not essential to maintain, the expression of these proteins.