Skeleton-binding protein 1 functions at the parasitophorous vacuole membrane to traffic PfEMP1 to the Plasmodium falciparum-infected erythrocyte surface.
ABSTRACT A key feature of Plasmodium falciparum, the parasite causing the most severe form of malaria in humans, is its ability to export parasite molecules onto the surface of the erythrocyte. The major virulence factor and variant surface protein PfEMP1 (P falciparum erythrocyte membrane protein 1) acts as a ligand to adhere to endothelial receptors avoiding splenic clearance. Because the erythrocyte is devoid of protein transport machinery, the parasite provides infrastructure for trafficking across membranes it traverses. In this study, we show that the P falciparum skeleton-binding protein 1 (PfSBP1) is required for transport of PfEMP1 to the P falciparum-infected erythrocyte surface. We present evidence that PfSBP1 functions at the parasitophorous vacuole membrane to load PfEMP1 into Maurer clefts during formation of these structures. Furthermore, the major reactivity of antibodies from malaria-exposed multigravid women is directed toward PfEMP1 because this is abolished in the absence of PfSBP1.
Article: A repetitive antigen of Plasmodium falciparum that is homologous to heat shock protein 70 of Drosophila melanogaster.[show abstract] [hide abstract]
ABSTRACT: We describe an antigen of Plasmodium falciparum, defined by a cDNA clone designated Ag63. The antigen is an abundant, soluble cytoplasmic polypeptide of Mr 75,000 present in all stages of asexual development in the blood and in gametocytes, but not in sporozoites. The sequence of the cDNA clone revealed that, like many other antigens of P. falciparum, it contains tandemly repeated amino acid sequences, in this case Gly-Gly-Met-Pro. However, the rest of the sequence is 70% homologous at the amino acid level to the heat shock protein hsp70 of Drosophila melanogaster.Proceedings of the National Academy of Sciences 12/1986; 83(22):8713-7. · 9.68 Impact Factor