Traffic pathways of Plasmodium vivax antigens during intraerythrocytic parasite development.
We investigated the secretory traffic of a Plasmodium vivax antigen (Pv-148) synthesised by the parasite during the blood cycle, exported into the host cell cytosol and then transported to the surface membrane of the infected erythrocyte. Studies of the ultrastructure of erythrocytes infected with P. vivax showed that intracellular schizogony is accompanied by the generation of parasite-induced membrane profiles in the erythrocyte cytoplasm. These structures are detectable soon after the parasite invades the erythrocyte and develop an elaborate organisation, leading to a tubovesicular membrane (TVM) network, in erythrocytes infected with mature trophozoites. Interestingly, the clefts formed stacked, flattened cisternae resembling a classical Golgi apparatus. The TVM network stained with the fluorescent Golgi marker Bodipy-ceramide. Specific immunolabelling showed that Pv-148 was transferred from the parasite to the erythrocyte surface membrane via the clefts and the TVM network. These findings suggest that the TVM network is part of the secretory pathways involved in parasite protein transport across the Plasmodium-infected erythrocyte and that Pv- 148 may represent a marker that links the parasite with the host cell cytoplasm and, in turn, with the extracellular milieu.
Bracho
Carmen
C
Instituto Venezolano de Investigaciones Cientificas, Centro de Microbiologia y Biologia Celular, Caracas, Venezuela.
Dunia
Irene
I
De
La Rosa Mercedes
LR
Benedetti
Ennio-Lucio
EL
Perez
Hilda A
HA
D000818:Animals; D000953:Antigens, Protozoan / Q000097:blood*; D000252:Calcium-Transporting ATPases / Q000097:blood; D003593:Cytoplasm / Q000469:parasitology; D004721:Endoplasmic Reticulum; D004910:Erythrocyte Membrane / Q000469:parasitology / Q000648:ultrastructure; D004912:Erythrocytes / Q000469:parasitology*; D006801:Humans; D008854:Microscopy, Electron; D016253:Microscopy, Immunoelectron; D010966:Plasmodium vivax / Q000502:physiology* / Q000648:ultrastructure; D012519:Sarcoplasmic Reticulum / Q000201:enzymology
D000953:Antigens, Protozoan; D000252:Calcium-Transporting ATPases