P23928 (CRYAB_RAT) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Alpha-crystallin B chain

Alternative name(s):
Alpha(B)-crystallin

Gene names

Name:

Cryab

Organism

Rattus norvegicus (Rat) [Reference proteome]

Taxonomic identifier

10116 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Mammalia › Theria › Eutheria › Euarchontoglires › Glires › Rodentia › Sciurognathi › Muroidea › Muridae › Murinae › Rattus

Protein attributes

Sequence length	175 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	May contribute to the transparency and refractive index of the lens. Has chaperone-like activity, preventing aggregation of various proteins under a wide range of stress conditions.
Subunit structure	Heteropolymer composed of three CRYAA and one CRYAB subunits. Aggregates with homologous proteins, including the small heat shock protein HSPB1, to form large heteromeric complexes. Inter-subunit bridging via zinc ions enhances stability, which is crucial as there is no protein turn over in the lens. Interacts with HSPBAP1 and TTN/titin By similarity. Ref.9
Subcellular location	Cytoplasm By similarity. Nucleus By similarity. Note: Translocates to the nucleus during heat shock and resides in sub-nuclear structures known as SC35 speckles or nuclear splicing speckles By similarity.
Tissue specificity	Lens as well as other tissues.
Developmental stage	Levels are low in both the slow-twitch soleus and fast-twitch rectus femoris muscles at prenatal day 2, then increase slowly until postnatal day 3. At 2 weeks, levels in the rectus femoris muscle then decrease while those in the soleus muscle increase sharply, reaching adult levels by 4 weeks. Ref.7
Sequence similarities	Belongs to the small heat shock protein (HSP20) family.
Sequence caution	The sequence CAA42911.1 differs from that shown. Reason: Erroneous initiation.

Ontologies

Keywords
Cellular component	Cytoplasm Nucleus
Ligand	Metal-binding Zinc
Molecular function	Chaperone Eye lens protein
PTM	Acetylation Glycoprotein Methylation Oxidation Phosphoprotein
Technical term	Complete proteome Direct protein sequencing Reference proteome
Gene Ontology (GO)
Biological_process	aging Inferred from expression pattern PubMed 17761354. Source: RGD apoptotic process involved in morphogenesis Inferred from electronic annotation. Source: Compara glucose metabolic process Inferred from mutant phenotype PubMed 15358243. Source: RGD lens development in camera-type eye Inferred from electronic annotation. Source: Compara microtubule polymerization or depolymerization Inferred from mutant phenotype PubMed 15075233. Source: RGD muscle organ development Inferred from electronic annotation. Source: Compara negative regulation of apoptotic process Inferred from direct assay PubMed 15358243. Source: RGD negative regulation of cell growth Inferred from direct assay PubMed 18974385. Source: RGD negative regulation of cysteine-type endopeptidase activity involved in apoptotic process Inferred from electronic annotation. Source: Compara negative regulation of gene expression Inferred from electronic annotation. Source: Compara negative regulation of intracellular transport Inferred from electronic annotation. Source: Compara negative regulation of reactive oxygen species metabolic process Inferred from direct assay PubMed 15358243. Source: RGD protein folding Inferred from direct assay PubMed 18158587. Source: RGD protein homooligomerization Inferred from electronic annotation. Source: Compara response to estradiol stimulus Inferred from expression pattern PubMed 17293487. Source: RGD response to hydrogen peroxide Inferred from expression pattern PubMed 18420382. Source: RGD response to hypoxia Inferred from electronic annotation. Source: Compara stress-activated MAPK cascade Inferred from mutant phenotype PubMed 18420382. Source: RGD tubulin complex assembly Inferred from electronic annotation. Source: Compara
Cellular_component	Golgi apparatus Inferred from direct assay PubMed 15339919. Source: RGD I band Inferred from direct assay PubMed 11945023. Source: RGD Z disc Inferred from electronic annotation. Source: Compara actin filament bundle Inferred from direct assay PubMed 10625651. Source: RGD cell surface Inferred from direct assay PubMed 17761354. Source: RGD cytosol Inferred from electronic annotation. Source: Compara microtubule cytoskeleton Inferred from direct assay PubMed 15075233. Source: RGD mitochondrion Inferred from electronic annotation. Source: Compara nucleus Inferred from sequence or structural similarity. Source: UniProtKB plasma membrane Inferred from electronic annotation. Source: Compara
Molecular_function	metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW microtubule binding Inferred from direct assay PubMed 15075233. Source: RGD protein homodimerization activity Inferred from sequence or structural similarity. Source: UniProtKB structural constituent of eye lens Traceable author statement Ref.6. Source: RGD
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 175	175	Alpha-crystallin B chain		PRO_0000125913
Sites
	Metal binding	104	1	Zinc By similarity
	Metal binding	111	1	Zinc By similarity
	Metal binding	119	1	Zinc By similarity
	Site	48	1	Susceptible to oxidation By similarity
	Site	60	1	Susceptible to oxidation By similarity
	Site	68	1	Susceptible to oxidation By similarity
Amino acid modifications
	Modified residue	1	1	N-acetylmethionine Probable
	Modified residue	19	1	Phosphoserine By similarity
	Modified residue	22	1	Omega-N-methylated arginine By similarity
	Modified residue	45	1	Phosphoserine By similarity
	Modified residue	50	1	Omega-N-methylated arginine By similarity
	Modified residue	59	1	Phosphoserine By similarity
	Modified residue	92	1	N6-acetyllysine By similarity
	Modified residue	166	1	N6-acetyllysine By similarity
	Glycosylation	170	1	O-linked (GlcNAc) Ref.8		CAR_000058

Sequences

	Sequence		Length	Mass (Da)
	P23928 [UniParc]. Last modified March 1, 1992. Version 1. Checksum: AB66796291518B9B	FASTA	175	20,089
	10 20 30 40 50 60 MDIAIHHPWI RRPFFPFHSP SRLFDQFFGE HLLESDLFST ATSLSPFYLR PPSFLRAPSW 70 80 90 100 110 120 IDTGLSEMRM EKDRFSVNLD VKHFSPEELK VKVLGDVIEV HGKHEERQDE HGFISREFHR 130 140 150 160 170 KYRIPADVDP LTITSSLSSD GVLTVNGPRK QASGPERTIP ITREEKPAVT AAPKK

References

[1]	"Multiple mRNAs of rat brain alpha-crystallin B chain result from alternative transcriptional initiation." Iwaki A., Iwaki T., Goldman J.E., Liem R.K. J. Biol. Chem. 265:22197-22203(1990) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[2]	"Alpha B-crystallin exists as an independent protein in the heart and in the lens." Bhat S.P., Horwitz J., Srinivasan A.N., Ding L. Eur. J. Biochem. 202:775-781(1991) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: Sprague-Dawley. Tissue: Heart and Lens.
[3]	"Early changes of alpha B-crystallin mRNA in rat skeletal muscle to mechanical tension and denervation." Atomi Y., Yamada S., Nishida T. Biochem. Biophys. Res. Commun. 181:1323-1330(1991) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Heart.
[4]	Srinivasan A.N., Bhat S.P. Submitted (DEC-1993) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: Wistar. Tissue: Spleen.
[5]	"Alpha B-crystallin in skeletal muscle: purification and localization." Atomi Y., Yamada S., Strohman R., Nonomura Y. J. Biochem. 110:812-822(1991) [PubMed] [Europe PMC] [Abstract] Cited for: PARTIAL PROTEIN SEQUENCE. Strain: Wistar. Tissue: Skeletal muscle.
[6]	"Alpha-B subunit of lens-specific protein alpha-crystallin is present in other ocular and non-ocular tissues." Bhat S.P., Nagineni C.N. Biochem. Biophys. Res. Commun. 158:319-325(1989) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 140-175. Tissue: Heart.
[7]	"Physiological and pathological changes in levels of the two small stress proteins, HSP27 and alpha B crystallin, in rat hindlimb muscles." Inaguma Y., Goto S., Shinohara H., Hasegawa K., Ohshima K., Kato K. J. Biochem. 114:378-384(1993) [PubMed] [Europe PMC] [Abstract] Cited for: DEVELOPMENTAL STAGE.
[8]	"Dynamic O-GlcNAcylation of the small heat shock protein alpha B-crystallin." Roquemore E.P., Chevrier M.R., Cotter R.J., Hart G.W. Biochemistry 35:3578-3586(1996) [PubMed] [Europe PMC] [Abstract] Cited for: GLYCOSYLATION AT THR-170.
[9]	"Identification and characterization of a novel protein from Sertoli cells, PASS1, that associates with mammalian small stress protein hsp27." Liu C., Gilmont R.R., Benndorf R., Welsh M.J. J. Biol. Chem. 275:18724-18731(2000) [PubMed] [Europe PMC] [Abstract] Cited for: INTERACTION WITH HSPBAP1.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	S74229 mRNA. Translation: AAB20759.1. S77138 mRNA. Translation: AAP31995.1. M55534 mRNA. Translation: AAA40977.1. X60352 mRNA. Translation: CAA42911.1. Different initiation. X60351 mRNA. Translation: CAA42910.1. S77142 mRNA. No translation available. U04320 Unassigned DNA. Translation: AAA03655.1. M24092 mRNA. Translation: AAA40978.1.
IPI	IPI00215465.
PIR	A23681.
RefSeq	NP_037067.1. NM_012935.3.
UniGene	Rn.98208.
3D structure databases
ProteinModelPortal	P23928.
ModBase	Search...
Protein-protein interaction databases
IntAct	P23928. 1 interaction.
MINT	MINT-6801317.
STRING	10116.ENSRNOP00000055901.
PTM databases
PhosphoSite	P23928.
Proteomic databases
PaxDb	P23928.
PRIDE	P23928.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
Ensembl	ENSRNOT00000059127; ENSRNOP00000055901; ENSRNOG00000010524.
GeneID	25420.
KEGG	rno:25420.
UCSC	RGD:2414. rat.
Organism-specific databases
CTD	1410.
RGD	2414. Cryab.
Phylogenomic databases
eggNOG	NOG246790.
GeneTree	ENSGT00550000074302.
HOGENOM	HOG000233954.
HOVERGEN	HBG054766.
KO	K09542.
OrthoDB	EOG4G1MHK.
Gene expression databases
Genevestigator	P23928.
GermOnline	ENSRNOG00000010524. Rattus norvegicus.
Family and domain databases
InterPro	IPR002068. a-crystallin/Hsp20_dom. IPR001436. Alpha-crystallin/HSP. IPR012273. Alpha-crystallin_B. IPR003090. Alpha-crystallin_N. IPR008978. HSP20-like_chaperone. [Graphical view]
PANTHER	PTHR11527:SF37. PTHR11527:SF37. 1 hit.
Pfam	PF00525. Crystallin. 1 hit. PF00011. HSP20. 1 hit. [Graphical view]
PIRSF	PIRSF036514. Sm_HSP_B1. 1 hit.
PRINTS	PR00299. ACRYSTALLIN.
SUPFAM	SSF49764. HSP20_chap. 1 hit.
PROSITE	PS01031. HSP20. 1 hit. [Graphical view]
ProtoNet	Search...
Other
NextBio	606579.

Entry information

Entry name

CRYAB_RAT

Accession

Primary (citable) accession number: P23928
Secondary accession number(s): Q6LDR2

Entry history

Integrated into UniProtKB/Swiss-Prot:	March 1, 1992
Last sequence update:	March 1, 1992
Last modified:	April 3, 2013
This is version 113 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program