Physiological role of PAFAH2, an oxidized phospholipid-hydrolyzing enzyme and PAFAH2-derived bioactive lipids

本研究结果如下：(1)利用免疫沉淀-质谱联用技术，鉴定了几种pafah2相互作用蛋白，包括PRDX2和SCP2。(2)从PAFAH2的突变分析中，发现Cys-83是PAFAH2对DTNB敏感的唯一残基，表明Cys-83的修饰可以调节PAFAH2的活性。(3)建立了一种检测PAFAH2从细胞质向细胞膜易位的免疫细胞化学方法。(4) pafah2缺陷小鼠表现出PCA反应减少，最可能是肥大细胞脱颗粒受损。(5) pafah2缺失小鼠骨髓来源的肥大细胞也显示ige依赖性脱颗粒减少。

In this study, we obtained following results:(1) Using immunoprecipitation coupled with mass spectrometry, several PAFAH2-interacting proteins including PRDX2 and SCP2 were identified.(2) From mutational analysis of PAFAH2, Cys-83 was found to be the only residue conferring sensitivity of PAFAH2 to DTNB, suggesting that PAFAH2 activity can be regulated by modification of Cys-83.(3) An immunocytochemical assay to detect the translocation of PAFAH2 from cytosol to membrane was established.(4) PAFAH2-deficient mice exhibited reduced PCA reaction most probably by impaired mast cell degranulation.(5) Bone marrow-derived mast cells from PAFAH2-deficient mice also showed decreased IgE-dependent degranulation.