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Biology subjects

Zou, B. Y.

Publications and source records attributed to Zou, B. Y..

3 recordsLinked to original sources

Plasmodium exoerythrocytic parasites redirect trafficking of human proteins to the parasitophorous vacuole

Changes in host cell morphology and transcription after apicomplexan parasite infection have long been noted, but there have been few studies of the functional consequences of host cell remodeling. Here we show, using time-dependent immunofluorescence microscopy of multiple human cell lines (HepG2, HC-04, Huh7.5.1 and primary human hepatocytes), infected with multiple Plasmodium species (Plasmodium berghei, P. falciparum and P. vivax (hypnozoites and schizonts)), and antibodies to multiple human proteins (HsNR4A3, HsMUC13, HsGOLGA8A, HsCGA, HsBiP, HsCXCL2), that human protein trafficking is extensively modified in Plasmodium infected cells. Using conventional as well as ultrastructure expansion microscopy we show that newly-synthesized human proteins are trafficked to the parasitophorous vacuole instead of the infected-cell plasma membrane, nucleus or extracellular space. Universal redirection of human signaling proteins cells the parasitophorous vacuole may provide a mechanistic explanation for how apicomplexan parasites can block host cells response to infection.

cell biology↗

Pan-active imidazolopiperazine antimalarials target the Plasmodium falciparum intracellular secretory pathway

AO_SCPLOWBSTRACTC_SCPLOWOne of the most promising new compound classes in clinical development for the treatment of malaria is the imidazolopiperazines (IZPs) class. Human trials have demonstrated that members of the IZP series, which includes KAF156 (Ganaplacide) and GNF179, are potent and effective against Plasmodium symptomatic asexual blood-stage infections. Unlike other commonly used antimalarials, they also prevent transmission and block future infection in animal models. Despite the identification of several Plasmodium falciparum resistance mechanisms including mutations in ER-localized PfCARL (PfEMP65), Acetyl-coA transporter, and PfUGT transporter, IZPs mechanism of action remains unknown.\n\nTo investigate, we combined in vitro evolution and whole-genome analysis in the model organism Saccharomyces cerevisiae with molecular, metabolomic, and chemogenomic methods, in P. falciparum. S. cerevisiae clones that resist IZP activity carry multiple mutations in genes that encode endoplasmic reticulum(ER)-based lipid homeostasis and autophagy including elo2, elo3, sur2, atg15 and lcb4, as well as ER-based sec66. In Plasmodium, IZPs cause inhibition of protein trafficking, block the establishment of new permeation pathways and result in ER expansion. We also observe sensitization with other secretion inhibitors such as brefeldin A and golgicidin as well as synthetic lethality with PfSEC62. Our data show that IZPs target the secretory pathway and highlight a novel mechanism for blocking parasite growth and development that is distinct from those of standard compounds used to treat malaria. In addition, we provide physiological signatures and hallmarks for inhibitors that work through this mechanism of action and show that IZPs are tool compounds for studying ER-dependent protein processing in different species.

microbiology↗

Dual RNAseq shows the human mucosal immunity protein, MUC13, is a hallmark of Plasmodium exoerythrocytic infection

The exoerythrocytic stage of Plasmodium malaria infection is a critical window for prophylactic intervention. Using a genome-wide dual RNA sequencing of flow-sorted infected and uninfected hepatoma cells we identify the human mucosal immunity gene, Mucin13 (MUC13), as strongly upregulated during Plasmodium exoerythrocytic hepatic-stage infection. We confirm that MUC13 expression is upregulated in hepatoma cell lines and primary hepatocytes. In immunofluorescence assays, host MUC13 protein expression distinguishes infected cells from adjacent uninfected cells and shows similar colocalization with parasite biomarkers such as UIS4 and HSP70. We further show that localization patterns are species independent, distinguishing both P. berghei and P. vivax infected cells, and that MUC13 can be used to identify compounds that inhibit parasite replication in hepatocytes across all Human-infecting Plasmodium species. This data presents a novel interface of host-parasite interactions in Plasmodium, in that a component of host mucosal immunity is reprogrammed to assist the progression of infection.

microbiology↗