CRYAA

CRYAA (Crystallin Alpha A) is a Protein Coding gene. Diseases associated with CRYAA include Cataract 9, Multiple Types and Cataract Microcornea Syndrome. Among its related pathways are Protein processing in endoplasmic reticulum and Regulation of degradation of deltaF508 CFTR in CF. Gene Ontology (GO) annotations related to this gene include identical protein binding and structural constituent of eye lens. An important paralog of this gene is CRYAA2.

Crystallin Alpha A

Contributes to the transparency and refractive index of the lens (PubMed:18302245).

In its oxidized form (absence of intramolecular disulfide bond), acts as a chaperone, preventing aggregation of various proteins under a wide range of stress conditions (PubMed:22120592, PubMed:31792453).

Required for the correct formation of lens intermediate filaments as part of a complex composed of BFSP1, BFSP2 and CRYAA (PubMed:28935373).

Negative regulation of apoptotic process Source: HGNC-UCL
Negative regulation of intracellular transport Source: HGNC-UCL
Protein stabilization Source: CAFA
Response to stimulus Source: UniProtKB-KW
Visual perception Source: UniProtKB

Cytoplasm; Nucleus. Translocates to the nucleus during heat shock and resides in sub-nuclear structures known as SC35 speckles or nuclear splicing speckles.

Alpha-crystallin A 1-172 is found at nearly twofold higher levels in diabetic lenses than in age-matched control lenses.
Cataract 9, multiple types (CTRCT9):
An opacification of the crystalline lens of the eye that frequently results in visual impairment or blindness. Opacities vary in morphology, are often confined to a portion of the lens, and may be static or progressive. In general, the more posteriorly located and dense an opacity, the greater the impact on visual function. CTRCT9 includes nuclear, zonular central nuclear, anterior polar, cortical, embryonal, anterior subcapsular, fan-shaped, and total cataracts, among others. In some cases cataract is associated with microcornea without any other systemic anomaly or dysmorphism. Microcornea is defined by a corneal diameter inferior to 10 mm in both meridians in an otherwise normal eye.

O-glycosylated; contains N-acetylglucosamine side chains.
Deamidation of Asn-101 in lens occurs mostly during the first 30 years of age, followed by a small additional amount of deamidation (approximately 5%) during the next approximately 38 years, resulting in a maximum of approximately 50% deamidation during the lifetime of the individual.
Phosphorylation on Ser-122 seems to be developmentally regulated. Absent in the first months of life, it appears during the first 12 years of human lifetime. The relative amount of phosphorylated form versus unphosphorylated form does not change over the lifetime of the individual.
Acetylation at Lys-70 may increase chaperone activity.
Undergoes age-dependent proteolytical cleavage at the C-terminus. Alpha-crystallin A(1-172) is the most predominant form produced most rapidly during the first 12 years of age and after this age is present in approximately 50% of the lens molecules.
In young individuals and during the first approximately 30 years of life, less than half molecules contain an intramolecular disulfide bond (oxidized form), while in the remaining fraction the cysteines are in the free sulfhydryl form (reduced form). With aging, the amount of oxidized form increases up to 90% and it becomes a major constituent of high molecular weight aggregates, concomitant with an age-dependent loss of its chaperone activity. The reduced form is undetectable in cataractous lenses.