Phosphatidylinositol N-acetylglucosaminyltransferase subunit A (PIG-A, or phosphatidylinositol glycan, class A) is the catalytic subunit of the

phosphatidylinositol N-acetylglucosaminyltransferase In enzymology, a phosphatidylinositol N-acetylglucosaminyltransferase () is an enzyme that catalyzes the chemical reaction :UDP-''N''-acetylglucosamine + phosphatidylinositol \rightleftharpoons UDP + ''N''-acetyl-D-glucosaminylphosphatidylinosito ...

enzyme, which in humans is encoded by the ''PIGA''

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

. This gene encodes a protein required for synthesis of N-acetylglucosaminyl phosphatidylinositol (GlcNAc-PI), the first intermediate in the biosynthetic pathway of GPI anchor. The

GPI anchor Glycosylphosphatidylinositol () or glycophosphatidylinositol (GPI) is a phosphoglyceride that can be attached to the C-terminus of a protein during posttranslational modification. The resulting GPI-anchored proteins play key roles in a wide vari ...

is a glycolipid found on many blood cells and serves to anchor proteins to the cell surface.

Paroxysmal nocturnal hemoglobinuria Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired, life-threatening disease of the blood characterized by destruction of red blood cells by the complement system, a part of the body's innate immune system. This destructive process ...

, an acquired hematologic disorder, has been shown to result from somatic mutations in this gene. Alternate splice variants have been characterized. Multiple Congenital Anomalies-Hypotonia-Seizures syndrome type 2 (MCAHS2), also known as PIGA-CDG or PIGA deficiency, has been shown to result from

germline mutation A germline mutation, or germinal mutation, is any detectable variation within germ cells (cells that, when fully developed, become sperm and Egg cell, ova). Mutations in these cells are the only mutations that can be passed on to offspring, when e ...

s in the PIGA gene.

Interactions

PIGA has been shown for

interact Advocates for Informed Choice, dba interACT or interACT Advocates for Intersex Youth, is a 501(c)(3) nonprofit organization advocating for the legal and human rights of children with intersex traits. The organization was founded in 2006 and fo ...

with

PIGQ Phosphatidylinositol N-acetylglucosaminyltransferase subunit Q is an enzyme that in humans is encoded by the ''PIGQ'' gene. This gene is involved in the first step in glycosylphosphatidylinositol (GPI)-anchor biosynthesis. The GPI-anchor is a gly ...

Interactions

References

Further reading