PAFAH2 hydrolyses PAF to lyso-PAF and acetate

Stable Identifier
R-HSA-8869206
Type
Reaction [transition]
Species
Homo sapiens
Compartment
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Platelet-activating factor acetylhydrolase 2 (PAFAH2) (Rice et al. 1998) is an intracellular phospholipase A2 enzyme that inactivates the potent phospholipid mediator platelet-activating factor (PAF) and other structurally similar bioactive lipids produced in response to oxidative stress. PAFAH2 hydrolyses PAF at the sn-2 position, producing lyso-PAF and acetate (CH3COO-). Following oxidative stress, cytoplasmic PAFAH2 (present in homodimeric form) trafficks to the membranes of both the endoplasmic reticulum and Golgi apparatus; membrane localisation is critical for substrate acquisition and effective oxidative stress protection (Thevenin et al. 2011, Monillas et al. 2015). The enzyme that performs the last step in PAF synthesis is located on the outer leaf of the ER membrane. PAFAH2 ER localisation would allow it to access newly synthesized PAF, potentially serving as a control mechanism for PAF levels.

Literature References
PubMed ID Title Journal Year
25707358 Oligomeric state regulated trafficking of human platelet-activating factor acetylhydrolase type-II

Monillas, ES, Caplan, JL, Thévenin, AF, Bahnson, BJ

Biochim. Biophys. Acta 2015
21882811 Trafficking of platelet-activating factor acetylhydrolase type II in response to oxidative stress

Thévenin, AF, Monillas, ES, Winget, JM, Czymmek, K, Bahnson, BJ

Biochemistry 2011
9494101 Expression, purification and characterization of a human serine-dependent phospholipase A2 with high specificity for oxidized phospholipids and platelet activating factor

Rice, SQ, Southan, C, Boyd, HF, Terrett, JA, MacPhee, CH, Moores, K, Gloger, IS, Tew, DG

Biochem. J. 1998
Participants
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Catalyst Activity
Catalyst Activity
Title
1-alkyl-2-acetylglycerophosphocholine esterase activity of PAFAH2 [endoplasmic reticulum membrane]
Physical Entity
Activity
Orthologous Events
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Created