The analysis of thousands of proteins in the brain has revealed the association of astrocytes with obsessive-compulsive disorder (OCD). A proteomic study by researchers from the University of California Los Angeles (UCLA) has identified them in different cellular compartments of astrocytes and neurons. One such protein, the postsynaptic protein SAPAP3, appeared to regulate the organization of the actin cytoskeleton. Its deficit in astrocytes could cause OCD.