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Crystallin, beta A4
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols CRYBA4 ; MCOPCT4
External IDs OMIM123631 MGI102716 HomoloGene1422 GeneCards: CRYBA4 Gene
RNA expression pattern
PBB GE CRYBA4 206843 at tn.png
More reference expression data
Species Human Mouse
Entrez 1413 12959
Ensembl ENSG00000196431 ENSMUSG00000066975
UniProt P53673 Q9JJV0
RefSeq (mRNA) NM_001886 NM_021351
RefSeq (protein) NP_001877 NP_067326
Location (UCSC) Chr 22:
27.02 – 27.03 Mb
Chr 5:
112.25 – 112.25 Mb
PubMed search [1] [2]

Beta-crystallin A4 is a protein that in humans is encoded by the CRYBA4 gene.[1][2][3]

Crystallins are separated into two classes: taxon-specific, or enzyme, and ubiquitous. The latter class constitutes the major proteins of vertebrate eye lens and maintains the transparency and refractive index of the lens. Since lens central fiber cells lose their nuclei during development, these crystallins are made and then retained throughout life, making them extremely stable proteins. Mammalian lens crystallins are divided into alpha, beta, and gamma families; beta and gamma crystallins are also considered as a superfamily. Alpha and beta families are further divided into acidic and basic groups. Seven protein regions exist in crystallins: four homologous motifs, a connecting peptide, and N- and C-terminal extensions. Beta-crystallins, the most heterogeneous, differ by the presence of the C-terminal extension (present in the basic group, none in the acidic group). Beta-crystallins form aggregates of different sizes and are able to self-associate to form dimers or to form heterodimers with other beta-crystallins. This gene, a beta acidic group member, is part of a gene cluster with beta-B1, beta-B2, and beta-B3.[3]


  1. ^ Lampi KJ, Ma Z, Shih M, Shearer TR, Smith JB, Smith DL, David LL (Feb 1997). "Sequence analysis of betaA3, betaB3, and betaA4 crystallins completes the identification of the major proteins in young human lens". J Biol Chem 272 (4): 2268–75. doi:10.1074/jbc.272.4.2268. PMID 8999933. 
  2. ^ Schuschke G, Mielke U, Bodamer S, Rosenkranz M (Oct 1976). "[Feral domestic pigeons as a hygienic problem in big cities--the situation in Magdeburg]". Z Gesamte Hyg 22 (1): 30–4. PMID 960806. 
  3. ^ a b "Entrez Gene: CRYBA4 crystallin, beta A4". 

Further reading[edit]