XYLT2 Gene: Xylosyltransferase 2
Key enzyme in proteoglycan biosynthesis and its role in skeletal disorders
Gene Information Card
| Symbol | XYLT2 |
|---|---|
| Full Name | Xylosyltransferase 2 |
| Gene Type | Protein-coding |
| Chromosomal Location | 17q21.33 |
| NCBI Gene ID | 64132 ncbi.nlm.nih.gov/gene/64132 |
| Ensembl ID | ENSG00000108379 |
| UniProt ID | Q9H1B5 |
| OMIM ID | 608125 |
| HGNC ID | 15518 |
| Aliases | PXYLT2, XT-II, XT2, xylT-II |
Description
The XYLT2 gene encodes xylosyltransferase 2, an enzyme that catalyzes the transfer of xylose from UDP-xylose to specific serine residues of proteoglycan core proteins, initiating the biosynthesis of glycosaminoglycan chains. This modification is essential for the function of proteoglycans in extracellular matrix organization, cell signaling, and development. Mutations in XYLT2 are associated with autosomal recessive spondyloocular syndrome, characterized by skeletal abnormalities, hearing loss, and cataracts.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Spondyloocular syndrome | Loss-of-function mutations in XYLT2 impair proteoglycan glycosylation, leading to defective bone and eye development. | OMIM #605822; PMID: 25558065 |
| Hearing loss (sensorineural) | Disrupted proteoglycan synthesis in inner ear structures due to XYLT2 deficiency. | ClinVar; PMID: 25558065 |
| Cataracts (congenital) | Abnormal proteoglycan composition in lens extracellular matrix. | OMIM #605822 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Liver | 12.5 | Medium |
| Kidney | 8.3 | Medium |
| Heart | 6.1 | Low |
| Brain | 4.7 | Low |
| Lung | 3.9 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HepG2 | 10.2 | Hepatocellular carcinoma cell line |
| HEK 293 | 7.8 | Embryonic kidney cells |
| A549 | 5.4 | Lung carcinoma cells |
| K562 | 2.1 | Leukemia cells |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1253C>T (p.Pro418Leu) | Missense | Rare | Loss of enzyme activity; associated with spondyloocular syndrome |
| c.1552C>T (p.Arg518*) | Nonsense | Rare | Premature truncation; loss of function |
| c.1045_1046del (p.Leu349Valfs*12) | Frameshift | Rare | Loss of function |
Mutation functional classification
Loss of Function (LOF)
Most XYLT2 mutations are loss-of-function, reducing or abolishing xylosyltransferase activity, leading to incomplete glycosaminoglycan chain initiation.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations reported; disease is autosomal recessive.
View complete mutation data：
Gene Ontology (GO)
| • xylosyltransferase activity (GO:0042285) | • UDP-xylose transmembrane transport (GO:0015787) |
| • proteoglycan biosynthetic process (GO:0015012) | • extracellular matrix organization (GO:0030198) |
| • Golgi apparatus (GO:0005794) |
Pathways
• Glycosaminoglycan biosynthesis - chondroitin sulfate / dermatan sulfate (KEGG: hsa00532)
• Glycosaminoglycan biosynthesis - heparan sulfate / heparin (KEGG: hsa00534)
• Proteoglycans in cancer (KEGG: hsa05205)
Protein Summary
Xylosyltransferase 2 (UniProt Q9H1B5) is a 559-amino acid type II transmembrane protein localized to the Golgi apparatus. It transfers xylose to serine residues of proteoglycan core proteins, the first and rate-limiting step in glycosaminoglycan chain synthesis. The enzyme requires manganese ions for activity and has a conserved DXD motif essential for catalysis. Defects in XYLT2 disrupt proteoglycan function, particularly in bone, eye, and inner ear tissues.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| GXYLT2 Knockout HEK293 Cell Line | EDJ-KQ13701 | Human | 727936 | Details Get a Quote |
| GXYLT2 Knockout A-549 Cell Line | EDJ-KQ43421 | Human | 727936 | Details Get a Quote |
| GXYLT2 Knockout HCT 116 Cell Line | EDJ-KQ43422 | Human | 727936 | Details Get a Quote |
| GXYLT2 Knockout HeLa Cell Line | EDJ-KQ43423 | Human | 727936 | Details Get a Quote |
| XYLT2 Knockout HAP1 Cell Line | EDC09332 | Human | 64132 | Details Get a Quote |
Displaying Records 1 To 5 Of 5 Records
