CHSY1: Chondroitin Sulfate Synthase 1
Key enzyme in glycosaminoglycan biosynthesis and skeletal development
Gene Information Card
| Symbol | CHSY1 |
|---|---|
| Full Name | Chondroitin Sulfate Synthase 1 |
| Gene Type | Protein coding |
| Chromosomal Location | 15q26.3 |
| NCBI Gene ID | 22856 ncbi.nlm.nih.gov/gene/22856 |
| Ensembl ID | ENSG00000137807 |
| UniProt ID | Q86X52 |
| OMIM ID | 608183 |
| HGNC ID | 18898 |
| Aliases | CHSY, CHSY-1, CSS1, KIAA0990 |
Description
CHSY1 encodes chondroitin sulfate synthase 1, a transmembrane glycosyltransferase involved in the biosynthesis of chondroitin sulfate, a major component of the extracellular matrix. The enzyme catalyzes the polymerization of chondroitin sulfate chains by transferring glucuronic acid and N-acetylgalactosamine residues. CHSY1 is essential for normal skeletal development, and its loss-of-function mutations cause Temtamy preaxial brachydactyly syndrome, characterized by limb malformations and intellectual disability.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Temtamy preaxial brachydactyly syndrome | Loss-of-function mutations in CHSY1 impair chondroitin sulfate synthesis, disrupting extracellular matrix signaling during limb development. | OMIM #605282; multiple families with homozygous or compound heterozygous mutations |
| Skeletal dysplasia with intellectual disability | Reduced chondroitin sulfate chain elongation affects cartilage and bone formation. | Case reports in ClinVar and literature (Li et al., 2010) |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 12.5 | Medium |
| Heart | 8.3 | Low |
| Liver | 3.1 | Low |
| Kidney | 6.7 | Low |
| Lung | 5.9 | Low |
| Skeletal muscle | 4.2 | Low |
| Placenta | 15.8 | Medium |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 18.2 | Embryonic kidney cells; high expression |
| HeLa | 9.5 | Cervical cancer cells; moderate expression |
| HepG2 | 4.1 | Hepatocellular carcinoma; low expression |
| K562 | 2.3 | Leukemia cells; very low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1019G>A (p.Arg340Gln) | Missense | Rare | Loss of enzymatic activity; associated with Temtamy syndrome |
| c.1435C>T (p.Arg479*) | Nonsense | Rare | Premature truncation; loss of function |
| c.1666_1667del (p.Leu556Glufs*12) | Frameshift | Rare | Loss of function; reported in ClinVar |
Mutation functional classification
Loss of Function (LOF)
Most CHSY1 disease-associated mutations are loss-of-function, leading to reduced chondroitin sulfate synthesis and skeletal defects.
Gain of Function (GOF)
No gain-of-function mutations reported in CHSY1.
Dominant Negative (DN)
No dominant-negative mutations described; inheritance is autosomal recessive.
View complete mutation data：
Gene Ontology (GO)
| • galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase activity (GO:0015018) | • glucuronosyltransferase activity (GO:0015020) |
| • acetylglucosaminyltransferase activity (GO:0008375) | • chondroitin sulfate biosynthetic process (GO:0030206) |
| • Golgi apparatus (GO:0005794) | • integral component of membrane (GO:0016021) |
Pathways
• Chondroitin sulfate / dermatan sulfate biosynthesis (Reactome: R-HSA-1971475)
• Glycosaminoglycan metabolism (KEGG: hsa00532)
Protein Summary
CHSY1 is a 759-amino acid type II transmembrane protein localized to the Golgi apparatus. It possesses dual glycosyltransferase activities: glucuronyltransferase and N-acetylgalactosaminyltransferase, enabling the elongation of chondroitin sulfate chains. The protein contains a short N-terminal cytoplasmic domain, a transmembrane domain, and a large luminal catalytic domain. Mutations that disrupt its catalytic activity lead to impaired chondroitin sulfate synthesis, resulting in skeletal abnormalities and neurodevelopmental deficits.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| CHSY1 Knockout HEK293 Cell Line | EDJ-KQ7697 | Human | 22856 | Details Get a Quote |
| CHSY1 Knockout A-549 Cell Line | EDJ-KQ33073 | Human | 22856 | Details Get a Quote |
| CHSY1 Knockout HCT 116 Cell Line | EDJ-KQ33074 | Human | 22856 | Details Get a Quote |
| CHSY1 Knockout HeLa Cell Line | EDJ-KQ33075 | Human | 22856 | Details Get a Quote |
Displaying Records 1 To 4 Of 4 Records
