5‐lipoxygenase‐activating protein is an arachidonate binding protein

[摘要]

5-Lipoxygenase-activating protein (FLAP) is an 18-kDa integral membrane protein which is essential for cellular leukotriene (LT) synthesis, and is the target of LT biosynthesis inhibitors. However, the mechanism by which FLAP activates 5-LO has not been determined. We have expressed high levels of human FLAP in Spodoptera frugiperda (Sf9) insect cells infected with recombinant baculovirus, and used this system to demonstrate that FLAP specifically binds [¹²⁵I]L-739,059, a novel photoaffinity analog of arachidonic acid. This binding is inhibited by both arachidonic acid and MK-886, an LT biosynthesis inhibitor which specifically interacts with FLAP. These studies suggest that FLAP may activate 5-LO by specifically binding arachidonic acid and transferring this substrate to the enzyme.

[学科分类] 生物化学/生物物理

[关键词] 5-Lipoxygenase-activating protein;5-Lipoxygenase;Arachidonic acid;Photoaffinity labeling;Baculovirus;5-HPETE;(5S)-hydroperoxy-6;8;11;14-eicosatetraenoic acid;LTA4;5;6-oxido-7;9;11;14-eicosatetraenoic acid;LTB4;(5S;12R)-dihydroxy-6;8;10;14-eicosatetraenoic acid;LTC4;(5S)-hydroxy-(6R)-S-glutathionyl-7;9;-(trans)-11;14-(cis)-eicosatetraenoic acid;LTD4;(5S)-hydroxy-(6R)-S-cysteinylglycyl-7;9-(trans)-11;14-(cis)-eicosatetraenoic acid;LTE4;(5S)-hydroxy-(6R)-S-cysteinyl-7;9-(trans)-11;14-(cis)-eicosatetraenoic acid;5-LO;5-lipoxygenase;FLAP;5-lipoxygenase-activating protein;MK.-886;3-[1-(p-chlorophenyl)-5-isopropyl-3-tert-butylthio-1H-indol-2-yl]-2;2-dimethylpropanoic acid (formerly designated L-663;536);L-691;831;((1-(4-iodobenzyl)-3-(3;3-dimethyl-1-oxo-1-butyl)-5-quinol-2-ylmethoxy)-indol-2-yl)-2;2-dimethyl propionic acid;L-691;678;1H-indole-2-propanoic acid;3-[(4-azidophenyl)sulfonyl]-2-[(4-iodophenyl)methyl]-α;α-dimethyl-5-(2-quinolinylmethoxy)-;DMSO;dimethyl sulphoxide;SDS-PAGE;sodium dodecyl sulphate polyacrylamide gel electrophoresis;EDTA;ethylenediamine tetraacetic acid;IC50;concentration required for 50% inhibition