Dynamics and function of phospholipase D and phosphatidic acid during phagocytosis.
Phospholipase D (PLD) produces phosphatidic acid (PA), an established intracellular signalling lipid that has been also implicated in vesicular trafficking, and as such, PLD could play multiple roles during phagocytosis. Using an RNA interference strategy, we show that endogenous PLD1 and PLD2 are necessary for efficient phagocytosis in murine macrophages, in line with results obtained with wild-type constructs and catalytically inactive PLD mutants which, respectively, enhance and inhibit phagocytosis. Furthermore, we found that PA is transiently produced at sites of phagosome formation. Macrophage PLD1 and PLD2 differ in their subcellular distributions. PLD1 is associated with cytoplasmic vesicles, identified as a late endosomal/lysosomal compartment, whereas PLD2 localizes at the plasma membrane. In living cells undergoing phagocytosis, PLD1 vesicles are recruited to nascent and internalized phagosomes, whereas PLD2 is only observed on nascent phagosomes. These results provide evidence that both PLD isoforms are required for phagosome formation, but only PLD1 seems to be implicated in later stages of phagocytosis occurring after phagosomal internalization.
Département Neurotransmission et Sécrétion Neuroendocrine, UMR 7168/LC2, CNRS/Université Louis Pasteur, Strasbourg, France.
Matthias
M
Corrotte
Sylvette
S
Chasserot-Golaz
Ping
P
Huang
Guangwei
G
Du
Nicholas T
NT
Ktistakis
Michael A
MA
Frohman
Nicolas
N
Vitale
Marie-France
MF
Bader
Nancy J
NJ
Grant
D000818:Animals; D002460:Cell Line; D005089:Exocytosis; D006801:Humans; D007074:Immunoglobulin G / Q000494:pharmacology; D007527:Isoenzymes / Q000276:immunology / Q000378:metabolism; D008264:Macrophages / Q000201:enzymology* / Q000276:immunology; D051379:Mice; D018613:Microscopy, Confocal; D018715:Microscopy, Video; D008863:Microspheres; D008954:Models, Biological; D010587:Phagocytosis / Q000276:immunology*; D010588:Phagosomes / Q000276:immunology / Q000378:metabolism; D010712:Phosphatidic Acids / Q000096:biosynthesis / Q000378:metabolism*; D010739:Phospholipase D / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D014168:Transferrin / Q000378:metabolism
D007074:Immunoglobulin G; D007527:Isoenzymes; D010712:Phosphatidic Acids; D012333:RNA, Messenger; D014168:Transferrin; D010739:Phospholipase D