Mapping the synaptic proteome through site-specific protein biotinylation

The multitude of neurons in the mammalian brain are interconnected trough a large number of cell-cell contacts called synapses. Neurons receive different types of information at distinct synapses that are anatomically segregated.  In addition to this segregation, different inputs have their own specific molecular, structural and functional characteristics that define their identity. Synapse identity and diversity are essential for the proper integration of this information and its conversion into neuronal output required for behavior and cognition. However, we know very little about the mechanisms synapses use to acquire their identity or the proteins that confer each synapse its particular morphological and functional properties. This project aims to implement a method for the identification of these processes. We are using CRISPR-Cas9 genome engineering in order to label and capture proteomes at specific synapses through proximity biotinylation. This powerful technique will help us uncover the molecular identity of two specific synapses on the same postsynaptic neuron. The subsequent comparison of these molecular compositions will yield important cues regarding the mechanisms required for the acquisition and maintenance of synapse identity