A Resource for Exploring Regional Diversity in the Male Rat Brain Synaptic Proteome.

The functional complexity of the mammalian brain is rooted in the diverse protein composition of synapses across distinct regions. To address the need for a detailed molecular understanding of this regional diversity, we generated the first comprehensive proteomic map of synaptosomes from six key rat brain regions: anterior cortex, posterior cortex, hippocampus, striatum, olfactory bulb, and cerebellum. Using high-resolution quantitative proteome and the Percoll density gradient ultracentrifugation, we identified 3,440 proteins and yielded high synaptic enrichment (60.11% synapse-unique proteins). In-depth functional analysis using the SynGO database revealed region-specific enrichments in the cellular components and biological processes. This study provides a valuable resource and foundational insights into the molecular architecture underlying regional synaptic diversity, paving the way for future investigations into brain function and neurological disorders.