Arachidonyltrifluoromethy Ketone, a Phospholipase A2 Antagonist, Induces Dispersal of Both Golgi Stack- and trans Golgi Network-Resident Proteins throughout the Cytoplasm

Abstract

Arachidonyltrifluoromethy ketone (AACOCF3), a phospholipase A2 antagonist, reversibly induced dispersal of Golgi stack- and trans Golgi network (TGN)-resident proteins throughout the cytoplasm in NRK cells as followed by immunocytochemical staining of ManII and TGN38, respectively. The action of AACOCF3 was partly blocked by other PLA2 antagonists, suggesting it be not caused by a general inhibition of phospholipase A2. AACOCF3 neither dissociated β-COP from membranes nor prevented brefeldin A-induced β-COP release. Action of AACOCF3 on the Golgi stack and TGN is different from that of brefeldin A and nordihydroguaiaretic acid. The most prominent difference is that the Golgi stack and TGN showed a similar sensitivity to AACOCF3, while the TGN was dispersed more slowly than the Golgi stack in brefeldin A- or nordihydroguaiaretic acid-treated NRK cells. This novel action of AACOCF3 may be used as pharmacological tool and give new insights into vesicle-mediated traffic and Golgi membrane dynamics.