RECOGNITION OF A 170 KD PROTEIN IN MAMMALIAN GOLGI COMPLEXES BY AN ANTIBODY AGAINST MALARIAL INTRAERYTHROCYTIC LAMELLAE

Human erythrocytes infected with the malarial parasite Plasmodium falc iparum contain flattened membrane lamellae, It has been suggested that the lamellae may be involved in the sorting of malarial proteins to t he cytoplasm and the cell membrane of the host erythrocyte. We have pr eviously shown that the lamellae accumulate sphingolipids by virtue of their lipid composition in a manner similar to the trans-Golgi and th e trans-Golgi network in mammalian cells, In this paper, we show by im munofluorescence microscopy that a monoclonal antibody to the lamellae labeled a perinuclear organelle that colocalized with WGA and the man nose-6-phosphate receptor in cultured mammalian cells, Immunoelectron microscopy experiments revealed that LWLI labels cisternae of the tran s-face and the trans-Golgi network, Western blot analysis of subcellul ar fractions using LWLI detected a 170 kD protein which is associated with the luminal side of Golgi membranes of rat liver and is conserved in all cell lines studied, Our results indicate that (i) the 170 kD p rotein is a novel marker of the mammalian trans-Golgi and the trans-Go lgi network and (ii) in addition to similarities in their morphologica l and lipid characteristics, the lamellae induced by P. falciparum in erythrocytes share proteinaceous determinants with the Golgi apparatus of mammalian cells.