CRYAB: Crystallin Alpha B – Chaperone and Structural Protein
A small heat shock protein linked to myopathy, cataract, cardiomyopathy, and multiple system atrophy
Gene Information Card
| Symbol | CRYAB |
|---|---|
| Full Name | Crystallin Alpha B |
| Gene Type | protein-coding |
| Chromosomal Location | 11q23.1 |
| NCBI Gene ID | 1410 ncbi.nlm.nih.gov/gene/1410 |
| Ensembl ID | ENSG00000109846 |
| UniProt ID | P02511 |
| OMIM ID | 123590 |
| HGNC ID | 2389 |
| Aliases | CRYA2, HSPB5, CTPP2, CTRCT16, MFM2, HEL-S-101 |
Description
CRYAB encodes alpha-crystallin B, a member of the small heat shock protein (sHSP) family. It functions as a molecular chaperone, preventing protein aggregation under stress conditions. The protein is constitutively expressed in the lens and also in cardiac and skeletal muscle, kidney, and brain. Mutations in CRYAB cause desmin-related myopathy, cardiomyopathy, and multiple types of cataract. The gene is also implicated in multiple system atrophy and certain cancers.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Cataract 16 multiple types (CTRCT16) | Missense mutations disrupt chaperone function, leading to lens protein aggregation | OMIM #613763 |
| Myopathy, myofibrillar, 2 (MFM2) | Dominant-negative or loss-of-function mutations cause desmin aggregation and myofibrillar disorganization | OMIM #608810 |
| Cardiomyopathy, dilated, 1II (CMD1II) | CRYAB mutations impair chaperone activity, leading to protein aggregation in cardiac muscle | OMIM #615184 |
| Multiple system atrophy (MSA) | CRYAB is a component of glial cytoplasmic inclusions; altered expression may contribute to neurodegeneration | NCBI Gene, PubMed |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Heart | 127.3 | High |
| Skeletal muscle | 89.6 | High |
| Lens (eye) | N/A (not in GTEx) | High (literature) |
| Kidney | 34.2 | Medium |
| Brain (cerebellum) | 22.1 | Medium |
| Liver | 1.2 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Cardiomyocytes (AC16) | 45.0 | High expression |
| Skeletal muscle myoblasts (LHCN-M2) | 38.5 | High expression |
| Lens epithelial cells (HLE-B3) | N/A | High (literature) |
| HEK293 | 12.3 | Moderate |
| HeLa | 8.7 | Low |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.451C>T (p.Arg151Cys) | Missense | Rare | Dominant-negative; causes cataract and myopathy |
| c.358A>G (p.Thr120Ala) | Missense | Rare | Gain-of-function?; associated with dilated cardiomyopathy |
| c.343C>T (p.Arg115Cys) | Missense | Rare | Loss of chaperone activity; myofibrillar myopathy |
| c.3G>A (p.Met1Ile) | Start loss | Very rare | Loss-of-function; severe early-onset myopathy |
Mutation functional classification
Loss of Function (LOF)
p.Met1Ile and certain missense variants reduce chaperone activity, leading to protein aggregation.
Gain of Function (GOF)
p.Thr120Ala may enhance aggregation propensity; not clearly established.
Dominant Negative (DN)
p.Arg151Cys and p.Arg115Cys interfere with wild-type CRYAB function, causing dominant disease.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Heat shock response (HSP pathway)
• Protein processing in endoplasmic reticulum (KEGG: hsa04141)
• Chaperone-mediated protein folding
Protein Summary
Alpha-crystallin B (CRYAB) is a 175-amino acid small heat shock protein (20.2 kDa) that forms oligomeric complexes. It binds partially unfolded proteins to prevent aggregation, especially under heat or oxidative stress. In the lens, it maintains transparency; in muscle, it protects desmin and other cytoskeletal proteins. Phosphorylation regulates its chaperone activity and subcellular localization.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| CRYAB Knockout HEK293 Cell Line | EDJ-KQ50209 | Human | 1410 | Details Get a Quote |
| CRYAB Knockout HeLa Cell Line | EDJ-KQ52987 | Human | 1410 | Details Get a Quote |
| CRYAB Knockout A-549 Cell Line | EDJ-KQ61454 | Human | 1410 | Details Get a Quote |
| CRYAB Knockout HCT 116 Cell Line | EDJ-KQ69951 | Human | 1410 | Details Get a Quote |
