B4GALT1 Gene - Beta-1,4-Galactosyltransferase 1
Key enzyme in glycoprotein and glycolipid biosynthesis, involved in congenital disorders of glycosylation and cancer.
Gene Information Card
| Symbol | B4GALT1 |
|---|---|
| Full Name | Beta-1,4-Galactosyltransferase 1 |
| Gene Type | Protein coding |
| Chromosomal Location | 9p21.1 |
| NCBI Gene ID | 2683 ncbi.nlm.nih.gov/gene/2683 |
| Ensembl ID | ENSG00000086062 |
| UniProt ID | P15291 |
| OMIM ID | 137060 |
| HGNC ID | 924 |
| Aliases | B4GAL-T1, GGTB2, GT1, GTB, beta4Gal-T1 |
Description
B4GALT1 encodes beta-1,4-galactosyltransferase 1, a type II membrane-bound glycoprotein that catalyzes the transfer of galactose from UDP-galactose to N-acetylglucosamine (GlcNAc) residues on glycoproteins and glycolipids. It is a key enzyme in the biosynthesis of N-linked and O-linked glycans, and also forms part of the lactose synthase complex. Mutations in B4GALT1 cause congenital disorder of glycosylation type IId (CDG IId). Altered expression is associated with various cancers.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Congenital disorder of glycosylation type IId (CDG IId) | Loss-of-function mutations in B4GALT1 impair N-glycan galactosylation, leading to multisystem developmental abnormalities. | OMIM #607091; ClinVar |
| Colorectal cancer | Overexpression of B4GALT1 enhances cell surface galactosylation, promoting tumor cell adhesion and metastasis. | PubMed; COSMIC |
| Hepatocellular carcinoma | Upregulation of B4GALT1 correlates with poor prognosis and increased metastatic potential. | PubMed; COSMIC |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Liver | 32.5 | High |
| Kidney | 18.2 | Medium |
| Small intestine | 15.8 | Medium |
| Pancreas | 12.1 | Medium |
| Lung | 8.4 | Low |
| Brain | 5.3 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HepG2 (liver) | 45.2 | High expression |
| HeLa (cervical) | 22.1 | Moderate expression |
| A549 (lung) | 9.7 | Low expression |
| MCF7 (breast) | 14.5 | Moderate expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.103C>T (p.Arg35Cys) | Missense | Rare | Loss of galactosyltransferase activity; associated with CDG IId |
| c.680G>A (p.Arg227His) | Missense | Rare | Reduced enzyme activity; reported in CDG IId |
| c.1A>G (p.Met1Val) | Start loss | Very rare | Complete loss of protein; severe CDG phenotype |
Mutation functional classification
Loss of Function (LOF)
Missense and start-loss mutations reduce or abolish galactosyltransferase activity, leading to CDG IId.
Gain of Function (GOF)
Not reported in B4GALT1.
Dominant Negative (DN)
Not reported in B4GALT1.
View complete mutation data：
Gene Ontology (GO)
| • galactosyltransferase activity (GO:0008378) | • protein glycosylation (GO:0006486) |
| • Golgi apparatus (GO:0005794) | • integral component of membrane (GO:0016021) |
| • glycosphingolipid biosynthetic process (GO:0006688) |
Pathways
• N-glycan biosynthesis (Reactome R-HSA-446203)
• Lactose synthesis (Reactome R-HSA-5653892)
• Glycosphingolipid biosynthesis (KEGG hsa00601)
Protein Summary
Beta-1,4-galactosyltransferase 1 is a 398-amino acid type II transmembrane protein localized to the Golgi apparatus. It catalyzes the transfer of galactose to terminal GlcNAc residues on glycoproteins and glycolipids, forming the Galβ1-4GlcNAc linkage. The protein has a short N-terminal cytoplasmic tail, a transmembrane domain, and a large luminal catalytic domain. It also associates with alpha-lactalbumin to form lactose synthase, enabling lactose production in the mammary gland.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| B4GALT1 Knockout HEK293 Cell Line | EDJ-KQ4707 | Human | 2683 | Details Get a Quote |
| B4GALT1 Knockout A-549 Cell Line | EDJ-KQ27426 | Human | 2683 | Details Get a Quote |
| B4GALT1 Knockout HCT 116 Cell Line | EDJ-KQ27427 | Human | 2683 | Details Get a Quote |
| B4GALT1 Knockout HeLa Cell Line | EDJ-KQ27428 | Human | 2683 | Details Get a Quote |
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