CIB2 Human
Description
Product Specs
Product Science Overview
CIB2 was first isolated from a cDNA library of human fetal brains by Seki et al. over two decades ago . The protein consists of 187 amino acids and has a broad distribution in various human tissues, including the brain, heart, kidney, lung, thymus, spleen, placenta, ovary, and testis . This widespread expression suggests that CIB2 plays a fundamental role in basic cellular functions.
CIB2 is a calcium-binding regulatory protein that interacts with DNA-dependent protein kinase catalytic subunits (DNA-PKcs). It plays a crucial role in intracellular calcium homeostasis and acts as an auxiliary subunit of the sensory mechanoelectrical transduction (MET) channel in hair cells . This function is essential for mechanoelectrical transduction currents in auditory hair cells, which are necessary for hearing .
CIB2 regulates the function of hair cell mechanotransduction by controlling the distribution of transmembrane channel-like proteins TMC1 and TMC2. It is also required for the maintenance of auditory hair cell stereocilia bundle morphology and function, as well as for hair-cell survival in the cochlea .
Mutations in the CIB2 gene have been associated with several disorders, including:
- Deafness, Autosomal Recessive 48 (DFNB48): This condition is characterized by non-syndromic hearing loss .
- Usher Syndrome Type 1J (USH1J): Usher syndrome is a genetic disorder that causes deafness and progressive vision loss .
In addition to its role in hearing, CIB2 has been implicated in various other processes, such as integrin signaling in platelets and skeletal muscle, and autophagy . This extensive functional plasticity highlights the importance of CIB2 in multiple physiological contexts.
Despite the significant progress in understanding the role of CIB2, many molecular aspects remain unclear and warrant further investigation. Future research aims to elucidate the detailed mechanisms by which CIB2 regulates calcium homeostasis and integrin signaling, as well as its potential involvement in other cellular processes.
