PIGP Gene - Phosphatidylinositol Glycan Anchor Biosynthesis Class P
Essential component of the GPI anchor biosynthesis pathway, implicated in inherited GPI deficiency and cancer
Gene Information Card
| Symbol | PIGP |
|---|---|
| Full Name | Phosphatidylinositol glycan anchor biosynthesis class P |
| Gene Type | Protein coding |
| Chromosomal Location | 21q22.13 |
| NCBI Gene ID | 51227 ncbi.nlm.nih.gov/gene/51227 |
| Ensembl ID | ENSG00000160207 |
| UniProt ID | O95427 |
| OMIM ID | 605938 |
| HGNC ID | 8963 |
| Aliases | DEE55, EIEE55, GPI7, MRT63, PIG-P |
Description
PIGP encodes phosphatidylinositol glycan anchor biosynthesis class P protein, a subunit of the glycosylphosphatidylinositol (GPI)-N-acetylglucosaminyltransferase (GPI-GnT) complex. This complex catalyzes the first step of GPI anchor biosynthesis, transferring N-acetylglucosamine to phosphatidylinositol. GPI anchors are essential for tethering proteins to the cell surface. Mutations in PIGP cause autosomal recessive intellectual developmental disorder with seizures (DEE55) and are associated with somatic alterations in cancer.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Developmental and epileptic encephalopathy 55 (DEE55) | Loss-of-function mutations in PIGP impair GPI anchor synthesis, leading to reduced cell surface expression of GPI-anchored proteins, disrupting neuronal development and function. | ClinVar, OMIM |
| Inherited GPI deficiency (IGD) | Biallelic PIGP mutations cause a spectrum of GPI deficiency disorders, including intellectual disability, seizures, and facial dysmorphism. | OMIM, NCBI |
| Cancer (somatic mutations) | Somatic missense and nonsense mutations in PIGP have been identified in various cancers, potentially affecting GPI-anchored protein expression and tumor immune evasion. | COSMIC |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 12.5 | Medium |
| Testis | 8.2 | Low |
| Lung | 6.1 | Low |
| Liver | 5.4 | Low |
| Kidney | 4.9 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 15.3 | High expression in embryonic kidney cells |
| HeLa | 10.1 | Moderate expression in cervical cancer cells |
| K562 | 7.8 | Low expression in leukemia cells |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Start loss | Rare | Loss of protein translation; associated with DEE55 |
| c.133C>T (p.Arg45*) | Nonsense | Rare | Premature stop; loss of function; ClinVar pathogenic |
| c.200G>A (p.Arg67His) | Missense | Somatic (COSMIC) | Unknown functional effect; observed in colorectal cancer |
Mutation functional classification
Loss of Function (LOF)
Biallelic loss-of-function mutations (e.g., start loss, nonsense) cause GPI deficiency and DEE55 by abolishing PIGP activity.
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) | • transferring glycosyl groups (GO:0016757) |
| • Endoplasmic reticulum membrane (GO:0005789) | • N-acetylglucosaminyltransferase complex (GO:0000506) |
Pathways
• GPI anchor biosynthesis (KEGG: hsa00563)
• Metabolism of proteins (Reactome: R-HSA-392499)
Protein Summary
PIGP is a 252-amino acid transmembrane protein localized to the endoplasmic reticulum. It is a component of the GPI-GnT complex, which catalyzes the first step of GPI anchor biosynthesis. The protein contains a single transmembrane domain and is essential for proper cell surface expression of GPI-anchored proteins. Defects in PIGP lead to neurological disorders and have been implicated in cancer.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| PIGP Knockout HEK293 Cell Line | EDJ-KQ10982 | Human | 51227 | Details Get a Quote |
| PIGP Knockout A-549 Cell Line | EDJ-KQ38811 | Human | 51227 | Details Get a Quote |
| PIGP Knockout HCT 116 Cell Line | EDJ-KQ38812 | Human | 51227 | Details Get a Quote |
| PIGP Knockout HeLa Cell Line | EDJ-KQ38813 | Human | 51227 | Details Get a Quote |
