PIGY: Phosphatidylinositol Glycan Anchor Biosynthesis Class Y
Essential component of the GPI transamidase complex involved in GPI anchor attachment
Gene Information Card
| Symbol | PIGY |
|---|---|
| Full Name | Phosphatidylinositol Glycan Anchor Biosynthesis Class Y |
| Gene Type | Protein coding |
| Chromosomal Location | 4q21.23 |
| NCBI Gene ID | 84992 ncbi.nlm.nih.gov/gene/84992 |
| Ensembl ID | ENSG00000138698 |
| UniProt ID | Q96N66 |
| OMIM ID | 610662 |
| HGNC ID | 26093 |
| Aliases | GPI7, PIG-Y, GPI transamidase subunit PIG-Y |
Description
PIGY encodes a subunit of the glycosylphosphatidylinositol (GPI) transamidase complex, which is essential for attaching GPI anchors to proteins. The GPI anchor is a glycolipid structure that tethers proteins to the cell surface. PIGY is a component of the GPI transamidase complex that recognizes the GPI attachment signal and mediates the transfer of the GPI anchor to the nascent protein. Mutations in PIGY cause a congenital disorder of glycosylation (PIGY-CDG) characterized by intellectual disability, seizures, and dysmorphic features.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| PIGY-CDG (Congenital Disorder of Glycosylation) | Loss-of-function mutations impair GPI anchor attachment, leading to reduced cell surface expression of GPI-anchored proteins | ClinVar, OMIM #610662 |
| Intellectual disability | Defective GPI anchoring disrupts neuronal protein function and signaling | OMIM #610662 |
| Seizures | Altered neuronal excitability due to deficient GPI-anchored proteins | OMIM #610662 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 12.5 | Medium |
| Liver | 8.3 | Low |
| Kidney | 10.1 | Medium |
| Heart | 7.6 | Low |
| Testis | 15.2 | High |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 14.0 | High expression |
| HeLa | 9.5 | Moderate expression |
| K562 | 6.8 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Missense | Rare | Loss of start codon, no protein production |
| c.97C>T (p.Arg33*) | Nonsense | Rare | Premature stop, loss of function |
| c.202G>A (p.Gly68Arg) | Missense | Rare | Impaired complex assembly |
Mutation functional classification
Loss of Function (LOF)
Most PIGY mutations are loss-of-function, leading to reduced GPI anchor attachment and decreased cell surface GPI-APs.
Gain of Function (GOF)
Not reported.
Dominant Negative (DN)
Not reported; inheritance is autosomal recessive.
View complete mutation data：
Gene Ontology (GO)
| • attachment of GPI anchor to protein (GO:0016255) | • glycosylphosphatidylinositol-N-acetylglucosaminyltransferase (GPI-GnT) complex (GO:0000506) |
| • integral component of membrane (GO:0016021) |
Pathways
• GPI anchor biosynthesis (Reactome: R-HSA-162791)
• GPI transamidase complex assembly (Reactome: R-HSA-163125)
Protein Summary
PIG-Y is a 149-amino-acid transmembrane protein that localizes to the endoplasmic reticulum. It is a structural subunit of the GPI transamidase complex, which also includes PIGK, PIGS, PIGT, and PIGU. PIG-Y stabilizes the complex and is required for efficient GPI anchor attachment. Without functional PIG-Y, GPI-anchored proteins are not properly expressed on the cell surface, leading to multisystem disorders.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| PIGY Knockout HEK293 Cell Line | EDJ-KQ10297 | Human | 84992 | Details Get a Quote |
| PIGY Knockout HCT 116 Cell Line | EDJ-KQ36320 | Human | 84992 | Details Get a Quote |
| PIGY Knockout A-549 Cell Line | EDJ-KQ37570 | Human | 84992 | Details Get a Quote |
| PIGY Knockout HeLa Cell Line | EDJ-KQ37572 | Human | 84992 | Details Get a Quote |
