Transport of phospholipid synthesis precursors and lipid trafficking into malaria-infected erythrocytes.
Phospholipid biosynthesis in Plasmodium is of crucial importance considering the high degree of membrane biogenesis. In the de novo phosphatidylcholine pathway, the major plasmodial phospholipid, choline, first enters infected erythrocytes by a transport-mediated process, whose main kinetic characteristics are the same as in normal cells except for a considerable increase in Vm. The kinetic and functional characterizations of the choline carrier (affinity, specificity, stereoselectivity, asymmetric cyclic model, ionic dependence, limiting step in carrier translocation) have now been done, although there is no information concerning its nature and structure, despite the fact that it is likely an outstanding pharmacological target. Other unanswered questions concern the mechanisms for choline entry into the parasite. The intense lipid trafficking between the intracellular parasite and the host cell membrane also indicates that Plasmodium controls its own lipid composition as well as that of its host cell. Organelles that house the machinery for lipid synthesis, and mechanisms for trafficking and sorting, have not yet been described because of the lack of appropriate tools, but they could address fundamental questions in the contemporary cell biology of this parasite.
Vial
H J
HJ
Dynamique Moléculaire des Interactions Membranaires, UMR 5539 CNRS, Université Montpellier II, France.
Eldin
P
P
Martin
D
D
Gannoun
L
L
Calas
M
M
Ancelin
M L
ML
D000818:Animals; D001693:Biological Transport, Active; D002794:Choline / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism / Q000469:parasitology*; D006801:Humans; D050356:Lipid Metabolism; D008288:Malaria / Q000097:blood*; D010743:Phospholipids / Q000096:biosynthesis*; D010961:Plasmodium
D010743:Phospholipids; D002794:Choline