PLA2G7

The protein encoded by this gene is a secreted enzyme that catalyzes the degradation of platelet-activating factor to biologically inactive products. Defects in this gene are a cause of platelet-activating factor acetylhydrolase deficiency. Two transcript variants encoding the same protein have been found for this gene.

Full Name

phospholipase A2 group VII

Function

Lipoprotein-associated calcium-independent phospholipase A2 involved in phospholipid catabolism during inflammatory and oxidative stress response (PubMed:7700381, PubMed:8624782, PubMed:2040620, PubMed:16371369, PubMed:17090529, PubMed:10066756).
At the lipid-aqueous interface, hydrolyzes the ester bond of fatty acyl group attached at sn-2 position of phospholipids (phospholipase A2 activity) (PubMed:2040620, PubMed:10504265).
Specifically targets phospholipids with a short-chain fatty acyl group at sn-2 position (PubMed:2040620).
Can hydrolyze phospholipids with long fatty acyl chains, only if they carry oxidized functional groups (PubMed:2040620, PubMed:8624782).
Hydrolyzes and inactivates platelet-activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine), a potent pro-inflammatory signaling lipid that acts through PTAFR on various innate immune cells (PubMed:10504265, PubMed:10066756, PubMed:7592717, PubMed:11590221, PubMed:7700381, PubMed:18434304, PubMed:16371369, PubMed:8675689, PubMed:8624782).
Hydrolyzes oxidatively truncated phospholipids carrying an aldehyde group at omega position, preventing their accumulation in low-density lipoprotein (LDL) particles and uncontrolled pro-inflammatory effects (PubMed:2040620, PubMed:7700381).
As part of high-density lipoprotein (HDL) particles, can hydrolyze phospholipids having long-chain fatty acyl hydroperoxides at sn-2 position and protect against potential accumulation of these oxylipins in the vascular wall (PubMed:17090529).
Catalyzes the release from membrane phospholipids of F2-isoprostanes, lipid biomarkers of cellular oxidative damage (PubMed:16371369).

Biological Process

Lipid oxidationManual Assertion Based On ExperimentIDA:BHF-UCL
Low-density lipoprotein particle remodelingManual Assertion Based On ExperimentIDA:BHF-UCL
Peptide hormone processingTAS:Reactome
Phosphatidylcholine catabolic processManual Assertion Based On ExperimentIDA:UniProtKB
Plasma lipoprotein particle oxidationManual Assertion Based On ExperimentIDA:BHF-UCL
Platelet activating factor catabolic processManual Assertion Based On ExperimentIDA:UniProtKB
Platelet activating factor metabolic processManual Assertion Based On ExperimentIDA:UniProtKB
Positive regulation of inflammatory responseManual Assertion Based On ExperimentTAS:BHF-UCL
Positive regulation of monocyte chemotaxisManual Assertion Based On ExperimentIDA:BHF-UCL

Cellular Location

Secreted, extracellular space
Associates with both LDL and HDL particles in plasma (PubMed:11590221, PubMed:12821559, PubMed:18434304, PubMed:10066756).
Mainly associates with pro-inflammatory electronegative LDL particles (PubMed:12821559).

Involvement in disease

Platelet-activating factor acetylhydrolase deficiency (PAFAD):
An enzymatic deficiency that results in exacerbated bodily response to inflammatory agents. It can be associated with several disease states including inflammatory gastrointestinal disorders, asthma and atopy. Asthmatic individuals with PAFAD may manifest aggravated respiratory symptoms.
Asthma (ASTHMA):
The most common chronic disease affecting children and young adults. It is a complex genetic disorder with a heterogeneous phenotype, largely attributed to the interactions among many genes and between these genes and the environment. It is characterized by recurrent attacks of paroxysmal dyspnea, with wheezing due to spasmodic contraction of the bronchi.
Atopic hypersensitivity (ATOPY):
A condition characterized by predisposition to develop hypersensitivity reactions. Atopic individuals can develop eczema, allergic rhinitis and allergic asthma.

PTM

N-glycosylated. Macrophage-derived PLA2G7 carries sialylated complex-type N-glycans that hinder its binding to HDL particles.