Calcium Binding Protein 1 (CABP1)

Calcium-binding protein 1, also known as caldendrin and calbrain, is a calcium-binding protein discovered in 1999. It has two EF hand motifs and is expressed in neuronal cells in such areas as hippocampus, habenular nucleus of the epithalamus, Purkinje cell layer of the cerebellum, and the amacrine cells and cone bipolar cells of the retina.

Cellular expression of caldendrin is restricted to the somato–dendritic compartment, with the exception of hypothalamus, where axonal labeling was detected.In schizophrenia, one study demonstrated a decrease in the number of CABP1-expressing cells, specifically in the left dorsolateral prefrontal cortex. This change, however, was compensated on a whole-brain scale by an increase in the protein levels.