Calcium-binding protein 1

Calcium binding protein 1 is a is_associated_with::protein that in humans is encoded by the CABP1 is_associated_with::gene. Calcium-binding protein 1 is a is_associated_with::calcium-binding protein discovered in 1999. It has two is_associated_with::EF hand motifs and is expressed in neuronal cells in such areas as is_associated_with::hippocampus, habenular nucleus of the is_associated_with::epithalamus, is_associated_with::Purkinje cell layer of the cerebellum, and the is_associated_with::amacrine cells and cone bipolar cells of the is_associated_with::retina.

Function
Calcium binding proteins are an important component of calcium mediated cellular signal transduction. This gene encodes a protein that belongs to a subfamily of calcium binding proteins which share similarity to calmodulin. The protein encoded by this gene regulates the gating of voltage-gated calcium ion channels. This protein causes rapid inactivation that is independent of Calcium, and does not support Calcium-dependent facilitation (Lee et al., 2002). This protein also regulates calcium-dependent activity of inositol 1,4,5-triphosphate receptors, P/Q-type voltage-gated calcium channels, and transient receptor potential channel TRPC5. This gene is predominantly expressed in retina and brain.

Cellular expression of caldendrin is restricted to the somato–dendritic compartment, with the exception of is_associated_with::hypothalamus, where is_associated_with::axonal labeling was detected.

Clinical significance
In is_associated_with::schizophrenia, one study demonstrated a decrease in the number of CABP1-expressing cells, specifically in the left is_associated_with::dorsolateral prefrontal cortex. This change, however, was compensated on a whole-brain scale by an increase in the protein levels.