Anti-Calretinin is developed in rabbit using a synthetic peptide corresponding to the C-terminal region of rat calretinin (amino acids 194-209) conjugated to keyhole limpet hemocyanin (KLH) as immunogen. Calretinin is an intracellular Ca2+-binding protein, with broad tissue distribution and is a member of the calmodulin superfamily. It is expressed in certain populations of neurons in the central and peripheral nervous systems. It is abundant in the cerebellum (granule cells), olfactory bulb and auditory pathways.
The physiological function of calretinin is not known, but it seems to be related to Ca2+ buffering and diffusion. Calretinin-deficient mice show impaired long-term potentiation (LTP) in the dentate gyrus, impaired motor coordination and Purkinje cell excitability. A role for both calretinin and calbindin-D-28K in synaptic plasticity and in neuroprotection from excitotoxic insults has been postulated. By acting as a buffer or sensor of intracellular free Ca2+, calretinin promotes calcium homeostasis. Furthermore, several truncated forms of calretinin have been found in certain tumor cells, but are absent from normal cells, suggesting that calretinin may play a role in tumorigenesis.
