P02489
uniprot
P02489
canonical
amino_acid_sequence
MDVTIQHPWFKRTLGPFYPSRLFDQFFGEGLFEYDLLPFLSSTISPYYRQSLFRTVLDSGISEVRSDRDKFVIFLDVKHFSPEDLTVKVQDDFVEIHGKHNERQDDHGYISREFHRRYRLPSNVDQSALSCSLSADGMLTFCGPKIQTGLDATHAERAIPVSREEKPTSAPSS
uniprot
proteins
disease_involvement
DISEASE: Note=Alpha-crystallin A 1-172 is found at nearly twofold higher levels in diabetic lenses than in age-matched control lenses. {ECO:0000269|PubMed:12356833}.; DISEASE: Cataract 9, multiple types (CTRCT9) [MIM:604219]: 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. {ECO:0000269|PubMed:11006246, ECO:0000269|PubMed:11123904, ECO:0000269|PubMed:14512969, ECO:0000269|PubMed:16453125, ECO:0000269|PubMed:16735993, ECO:0000269|PubMed:16862070, ECO:0000269|PubMed:17296897, ECO:0000269|PubMed:17724170, ECO:0000269|PubMed:17937925, ECO:0000269|PubMed:18199971, ECO:0000269|PubMed:18302245, ECO:0000269|PubMed:18407550, ECO:0000269|PubMed:18587492, ECO:0000269|PubMed:19182255, ECO:0000269|PubMed:19390652, ECO:0000269|PubMed:19503744, ECO:0000269|PubMed:19595763, ECO:0000269|PubMed:20465443, ECO:0000269|PubMed:21686328, ECO:0000269|PubMed:21866213, ECO:0000269|PubMed:22065922, ECO:0000269|PubMed:22216983, ECO:0000269|PubMed:23255486, ECO:0000269|PubMed:23288997, ECO:0000269|PubMed:23441109, ECO:0000269|PubMed:23508780, ECO:0000269|PubMed:24074001, ECO:0000269|PubMed:25729975, ECO:0000269|PubMed:26004348, ECO:0000269|PubMed:26867756, ECO:0000269|PubMed:28690483, ECO:0000269|PubMed:28839118, ECO:0000269|PubMed:29386872, ECO:0000269|PubMed:29914532, ECO:0000269|PubMed:30340470, ECO:0000269|PubMed:31523120, ECO:0000269|PubMed:32010934, ECO:0000269|PubMed:33243271, ECO:0000269|PubMed:9467006}. Note=The disease is caused by variants affecting the gene represented in this entry.
uniprot
proteins
function
FUNCTION: 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:18199971, PubMed:19595763, 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). {ECO:0000269|PubMed:18199971, ECO:0000269|PubMed:19595763, ECO:0000269|PubMed:22120592, ECO:0000269|PubMed:28935373, ECO:0000269|PubMed:31792453, ECO:0000303|PubMed:18302245}.
uniprot
proteins
mass_dalton
19909
uniprot
proteins
mutagenesis
MUTAGEN 123; /note="N->D: Impairs chaperone activity."; /evidence="ECO:0000269|PubMed:18754677
uniprot
proteins
post_translational_modification
PTM: O-glycosylated; contains N-acetylglucosamine side chains.; PTM: 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. {ECO:0000269|PubMed:18754677, ECO:0000269|PubMed:8175657, ECO:0000269|PubMed:9068373, ECO:0000269|PubMed:9543632, ECO:0000269|PubMed:9655350}.; PTM: 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. {ECO:0000269|PubMed:10930324, ECO:0000269|PubMed:8175657, ECO:0000269|PubMed:8759518, ECO:0000269|PubMed:9068373, ECO:0000269|PubMed:9655350}.; PTM: Acetylation at Lys-70 may increase chaperone activity. {ECO:0000269|PubMed:22120592, ECO:0000269|PubMed:817940, ECO:0000269|PubMed:9655350}.; PTM: 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. {ECO:0000269|PubMed:10930324, ECO:0000269|PubMed:12356833, ECO:0000269|PubMed:8175657, ECO:0000269|PubMed:9068373, ECO:0000269|PubMed:9655350}.; PTM: 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. {ECO:0000305|PubMed:31792453}.
uniprot
proteins
protein_family
Small heat shock protein (HSP20) family
uniprot
proteins
pubmed
10830953
uniprot
proteins
pubmed
10930324
uniprot
proteins
pubmed
11006246
uniprot
proteins
pubmed
11123904
uniprot
proteins
pubmed
12356833
uniprot
proteins
pubmed
12369933
uniprot
proteins
pubmed
14512969
uniprot
proteins
pubmed
15489334
uniprot
proteins
pubmed
16453125
uniprot
proteins
pubmed
16735993
uniprot
proteins
pubmed
16862070
uniprot
proteins
pubmed
16959974
uniprot
proteins
pubmed
17296897
uniprot
proteins
pubmed
1730617
uniprot
proteins
pubmed
17724170
uniprot
proteins
pubmed
17909943
uniprot
proteins
pubmed
17937925
uniprot
proteins
pubmed
18199971
uniprot
proteins
pubmed
18302245
uniprot
proteins
pubmed
18407550
uniprot
proteins
pubmed
18587492
uniprot
proteins
pubmed
18754677
uniprot
proteins
pubmed
19182255
uniprot
proteins
pubmed
19390652
uniprot
proteins
pubmed
19464326
uniprot
proteins
pubmed
19503744
uniprot
proteins
pubmed
19595763
uniprot
proteins
pubmed
20465443
uniprot
proteins
pubmed
20836128
uniprot
proteins
pubmed
21686328
uniprot
proteins
pubmed
21866213
uniprot
proteins
pubmed
22065922
uniprot
proteins
pubmed
22120592
uniprot
proteins
pubmed
22216983
uniprot
proteins
pubmed
22890888
uniprot
proteins
pubmed
23255486
uniprot
proteins
pubmed
23288997
uniprot
proteins
pubmed
23441109
uniprot
proteins
pubmed
23508780
uniprot
proteins
pubmed
24074001
uniprot
proteins
pubmed
25729975
uniprot
proteins
pubmed
26004348
uniprot
proteins
pubmed
26867756
uniprot
proteins
pubmed
28690483
uniprot
proteins
pubmed
28839118
uniprot
proteins
pubmed
28935373
uniprot
proteins
pubmed
2918909
uniprot
proteins
pubmed
29386872
uniprot
proteins
pubmed
29914532
uniprot
proteins
pubmed
30340470
uniprot
proteins
pubmed
31523120
uniprot
proteins
pubmed
31792453
uniprot
proteins
pubmed
32010934
uniprot
proteins
pubmed
33243271
uniprot
proteins
pubmed
3758227
uniprot
proteins
pubmed
8175657
uniprot
proteins
pubmed
817940
uniprot
proteins
pubmed
8587135
uniprot
proteins
pubmed
8759518
uniprot
proteins
pubmed
8943244
uniprot
proteins
pubmed
8999933
uniprot
proteins
pubmed
9068373
uniprot
proteins
pubmed
9467006
uniprot
proteins
pubmed
9543632
uniprot
proteins
pubmed
9655350
uniprot
proteins
sequence_length
173
uniprot
proteins
subcellular_location
SUBCELLULAR LOCATION: Cytoplasm {ECO:0000269|PubMed:14512969, ECO:0000269|PubMed:19464326, ECO:0000269|PubMed:19503744, ECO:0000269|PubMed:26004348, ECO:0000269|PubMed:30340470}. Nucleus {ECO:0000269|PubMed:19464326}. Note=Translocates to the nucleus during heat shock and resides in sub-nuclear structures known as SC35 speckles or nuclear splicing speckles.
uniprot
proteins