Calcium binding protein 2

Calcium binding protein 2, also known as CaBP2, is a protein that in humans is encoded by the CABP2 gene.

The CABP2 gene comprises 6 exons, spanning approximately 5 kb, and is situated on chromosome 11q13.1.

CaBP2 contain a consensus sequence for N-terminal myristoylation, akin to members of the recoverin subfamily, and undergoes fatty acid acylation in vitro.

Function and clinical significance
CaBP2 involves in calcium signaling and regulation. Specifically, CaBP2 is known for its ability to bind calcium ions, acting as a calcium sensor within cells. This interaction with calcium plays a crucial role in various cellular processes, including neurotransmitter release in neurons and modulation of ion channels. CaBP2 is found in the retina and plays a significant role in visual signal processing. It interacts with other proteins, including those involved in the phototransduction cascade, contributing to the regulation of calcium levels in response to light stimuli.

Moreover, The CaBP2 protein is highly expressed in the cochlea. Non-syndromic autosomal recessive hearing impairment DFNB93, caused by defects in the CABP2 gene. Genetic defects in CABP2 may result in moderate to severe sensorineural hearing impairment.

As of 2021, CaBP2-related non-syndromic hearing impairment has been reported in only a few families worldwide, including those in Iran, Turkey, Pakistan, Italy, and Denmark.