CRYAA

Alpha-crystallin A chain is a protein that in humans is encoded by the CRYAA gene.^[5]

CRYAA
Identifiers
Aliases	CRYAA, CRYA1, CTRCT9, HSPB4, crystallin alpha A
External IDs	OMIM: 123580; MGI: 88515; HomoloGene: 48053; GeneCards: CRYAA; OMA:CRYAA - orthologs
Gene location (Human) Chr. Chromosome 21 (human)[1] Band 21q22.3 Start 43,169,008 bp[1] End 43,172,805 bp[1]
Gene location (Mouse) Chr. Chromosome 17 (mouse)[2] Band 17 B1|17 17.09 cM Start 31,896,781 bp[2] End 31,900,707 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in right lobe of liver duodenum prefrontal cortex human kidney primary visual cortex Temporal Lobe Amygdala hippocampus proper anterior cingulate cortex caudate nucleus Top expressed in lens epithelium of lens corneal stroma neural layer of retina ciliary body conjunctival fornix retinal pigment epithelium iris decidua gastrula More reference expression data BioGPS More reference expression data
Gene ontology Molecular function unfolded protein binding protein binding metal ion binding structural constituent of eye lens identical protein binding Cellular component cytoplasm nucleus nucleoplasm cytosol Biological process negative regulation of intracellular transport negative regulation of apoptotic process protein homooligomerization protein refolding response to stimulus visual perception protein stabilization Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 1409 12954 Ensembl ENSG00000160202 ENSMUSG00000024041 UniProt P02489 P24622 RefSeq (mRNA) NM_000394 NM_001363766 NM_001278569 NM_001278570 NM_013501 RefSeq (protein) NP_000385 NP_001350695 NP_001300979 NP_001307648 NP_001265498 NP_001265499 NP_038529 Location (UCSC) Chr 21: 43.17 – 43.17 Mb Chr 17: 31.9 – 31.9 Mb PubMed search [3] [4]
Wikidata
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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. Alpha crystallins are composed of two gene products: alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein (sHSP also known as the HSP20) family. They act as molecular chaperones although they do not renature proteins and release them in the fashion of a true chaperone; instead they hold them in large soluble aggregates. Post-translational modifications decrease the ability to chaperone. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional functions of alpha crystallins are an autokinase activity and participation in the intracellular architecture. Alpha-A and alpha-B gene products are differentially expressed; alpha-A is preferentially restricted to the lens and alpha-B is expressed widely in many tissues and organs. Defects in this gene cause autosomal dominant congenital cataract (ADCC).^[5]

Interactions

CRYAA has been shown to interact with CRYBB2,^[6] Hsp27,^[6] CRYGC^[6] and CRYAB.^[6]