CRYBB3
Description
The CRYBB3 (crystallin beta B3) is a protein-coding gene located on chromosome 22.
Beta-crystallin B3 is a protein encoded by the CRYBB3 gene in humans. Crystallins are divided into two classes: taxon-specific (enzyme) and ubiquitous. Ubiquitous crystallins are the primary proteins in the vertebrate eye lens, responsible for maintaining its transparency and refractive index. These crystallins are produced and retained throughout life due to the loss of nuclei in central lens fiber cells during development, making them exceptionally stable. Mammalian lens crystallins are categorized into alpha, beta, and gamma families, with beta and gamma crystallins also considered a superfamily. Alpha and beta families are further divided into acidic and basic groups. Crystallins share seven protein regions: four homologous motifs, a connecting peptide, and N- and C-terminal extensions. Beta-crystallins, the most diverse, are differentiated by the presence or absence of a C-terminal extension (present in basic group, absent in acidic group). They form aggregates of varying sizes and can self-associate to form dimers or heterodimers with other beta-crystallins. This gene, a member of the beta basic group, belongs to a gene cluster that includes beta-A4, beta-B1, and beta-B2.
CRYBB3 is also known as CATCN2, CRYB3, CTRCT22.