PIGT Gene - Phosphatidylinositol Glycan Anchor Biosynthesis Class T
Essential component of the GPI transamidase complex involved in glycosylphosphatidylinositol (GPI) anchor attachment
Gene Information Card
| Symbol | PIGT |
|---|---|
| Full Name | Phosphatidylinositol Glycan Anchor Biosynthesis Class T |
| Gene Type | Protein coding |
| Chromosomal Location | 20q13.12 |
| NCBI Gene ID | 51604 ncbi.nlm.nih.gov/gene/51604 |
| Ensembl ID | ENSG00000124155 |
| UniProt ID | Q969N2 |
| OMIM ID | 610272 |
| HGNC ID | 14938 |
| Aliases | GPI7, PIG-T, GPI transamidase component PIG-T |
Description
The PIGT gene encodes a subunit of the glycosylphosphatidylinositol (GPI) transamidase complex, which is essential for attaching GPI anchors to proteins. GPI-anchored proteins are tethered to the cell membrane and play critical roles in cell signaling, adhesion, and immune recognition. Mutations in PIGT cause a form of inherited GPI anchor deficiency (IGDA) characterized by multiple congenital anomalies, hypotonia, seizures, and intellectual disability.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Multiple congenital anomalies-hypotonia-seizures syndrome 3 (MCAHS3) | Loss-of-function mutations in PIGT impair GPI anchor attachment, leading to reduced cell surface expression of GPI-anchored proteins | OMIM #615398; PMID: 23768512 |
| Inherited GPI deficiency (IGD) | Biallelic PIGT mutations disrupt GPI transamidase activity, causing global GPI anchor deficiency | ClinVar; PMID: 23768512 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 15.2 | Medium |
| Liver | 12.8 | Medium |
| Heart | 10.5 | Medium |
| Kidney | 9.3 | Low |
| Lung | 8.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 18.4 | High expression |
| HeLa | 14.7 | Medium expression |
| K562 | 11.2 | Medium expression |
| HepG2 | 9.8 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.534G>A (p.Trp178*) | Nonsense | Rare | Loss of function; premature stop codon |
| c.718C>T (p.Arg240*) | Nonsense | Rare | Loss of function; premature stop codon |
| c.1A>G (p.Met1?) | Missense | Rare | Loss of function; start codon loss |
Mutation functional classification
Loss of Function (LOF)
Biallelic loss-of-function mutations in PIGT cause GPI anchor deficiency, leading to MCAHS3 and IGD.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations reported.
View complete mutation data：
Gene Ontology (GO)
| • GPI anchor biosynthetic process (GO:0006506) | • GPI-anchor transamidase activity (GO:0015926) |
| • Endoplasmic reticulum membrane (GO:0005789) | • Integral component of membrane (GO:0016021) |
Pathways
• GPI anchor biosynthesis (Reactome: R-HSA-162710)
• GPI-anchored protein processing (KEGG: hsa00563)
Protein Summary
PIGT is a 578-amino acid transmembrane protein localized to the endoplasmic reticulum. It forms the catalytic core of the GPI transamidase complex, which cleaves the GPI signal peptide and attaches the GPI anchor to nascent proteins. The protein contains a conserved cysteine-rich domain and is essential for cell surface expression of GPI-anchored proteins.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| PIGT Knockout HEK293 Cell Line | EDJ-KQ2207 | Human | 51604 | Details Get a Quote |
| PIGT Knockout A-549 Cell Line | EDJ-KQ21152 | Human | 51604 | Details Get a Quote |
| PIGT Knockout HCT 116 Cell Line | EDJ-KQ22462 | Human | 51604 | Details Get a Quote |
| PIGT Knockout HeLa Cell Line | EDJ-KQ22463 | Human | 51604 | Details Get a Quote |
