Synapses structure

Robust decreases in the expression of the various proteasome subunits and ubiquitin-conjugating enzymes have been described in prefrontal cortex in schizophrenia. Neuronal ubiquitin and proteasomes play an important role in the assembly, function and plasticity of the synapse. Structural proteins including tubulin and a-spectrin also show decreased expression in prefrontal cortex. 

Budnik V, Koh Y.-H., Guan B., Hartmann B., Hough C., Woods D., and Gorczyca M. 1996. Regulation of synapse structure and function by the Drosophila tumor suppressor gene dig. Neuron 17 627-640. 

Apparently, not all cell contacts are able to transfer an impulse at any given moment. These contacts function only at a certain time of animal learning. In other words, the establishment of contacts between neurons does not mean there is a functional association between them. Additional structural-physiological transformations in the synaptic apparatus are necessary for its function. These transformations initiate the beginning of the synapsis function. 

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