A5007824523- Malaria Research and Control
- Mosquito-borne diseases and control
- Research on Leishmaniasis Studies
- Trypanosoma species research and implications
- Invertebrate Immune Response Mechanisms
- HIV Research and Treatment
- Complement system in diseases
- Toxoplasma gondii Research Studies
- Traditional and Medicinal Uses of Annonaceae
- Drug Transport and Resistance Mechanisms
- Biochemical and Molecular Research
- Wastewater Treatment and Reuse
- Metabolomics and Mass Spectrometry Studies
- Computational Drug Discovery Methods
- Advanced Proteomics Techniques and Applications
- Parasites and Host Interactions
- Cellular transport and secretion
- Phytochemical compounds biological activities
- Bacteriophages and microbial interactions
- Marine Sponges and Natural Products
- Mass Spectrometry Techniques and Applications
- Essential Oils and Antimicrobial Activity
- Redox biology and oxidative stress
- Myeloproliferative Neoplasms: Diagnosis and Treatment
- Insects and Parasite Interactions
Université Laval
2015-2024
Stony Brook University
2023
State University of New York
2023
Centre hospitalier de l'Université Laval
2002-2023
Centre hospitalier universitaire de Québec
2004-2012
Walter and Eliza Hall Institute of Medical Research
2005-2011
Centre National de la Recherche Scientifique
2003
Apicomplexan parasites constitute one of the most significant groups pathogens infecting humans and animals. The liver stage sporozoites Plasmodium spp. tachyzoites Toxoplasma gondii, causative agents malaria toxoplasmosis, respectively, use a unique mode locomotion termed gliding motility to invade host cells cross cell substrates. This amoeboid-like movement uses parasite adhesin from thrombospondin-related anonymous protein (TRAP) family set proteins linking extracellular adhesin, via an...
Invasion of host cells by apicomplexan parasites, including Plasmodium falciparum and Toxoplasma gondii, is a multistep process. Central to invasion the formation tight junction, an aperture in cell through which parasite pulls itself before settling into newly formed parasitophorous vacuole. Two protein groups, derived from different secretory organelles, micronemal AMA1 rhoptry proteins RON2, RON4, RON5, have been shown form part this structure, with antibodies targeting P. known inhibit...
The <i>Leishmania</i>ATP-binding cassette (ABC) transporter PGPA is involved in metal resistance (arsenicals and antimony), although the exact mechanism by which confers to antimony, first line drug against<i>Leishmania</i>, unknown. results of co-transfection experiments, transport assays, use inhibitors suggest that recognizes metals conjugated glutathione or trypanothione, a glutathione-spermidine conjugate present <i>Leishmania</i>. HA epitope tag influenza hemagglutinin as well green...
Plasmodium falciparum is responsible for the most severe form of malaria disease in humans, causing more than 1 million deaths each year. As an obligate intracellular parasite, P. falciparum's ability to invade erythrocytes essential its survival within human host. invades using multiple host receptor-parasite ligand interactions known as invasion pathways. Here we show that CR1 erythrocyte receptor PfRh4, a major sialic acid-independent invasion. PfRh4 and interact directly, with K(d) 2.9...
Invasion of erythrocytes by Plasmodium falciparum involves a complex cascade protein-protein interactions between parasite ligands and host receptors. The reticulocyte binding-like homologue (PfRh) protein family is involved in binding to initiating entry the invasive merozoite into erythrocytes. An important member this PfRh5. Using ion-exchange chromatography, immunoprecipitation mass spectroscopy, we have identified novel cysteine-rich called P. Rh5 interacting (PfRipr) (PFC1045c), which...
Abstract Plasmodium falciparum exports proteins into erythrocytes using the export element (PEXEL) motif, which is cleaved in endoplasmic reticulum (ER) by plasmepsin V (PMV). A recent study reported that phosphatidylinositol-3-phosphate (PI(3)P) concentrated ER binds to PEXEL motifs and required for independent of PMV, are functionally interchangeable with RxLR oomycete effectors. Here we show does not bind PI(3)P, this lipid ER. We find cannot mediate P. . Parasites expressing a mutated...
ABSTRACT A 761-bp portion of the tuf gene (encoding elongation factor Tu) from 28 clinically relevant streptococcal species was obtained by sequencing amplicons generated using broad-range PCR primers. These sequences were used to select Streptococcus -specific primers and perform phylogenetic analysis. The specificity assay verified 102 different bacterial species, including species. Genomic DNA purified all efficiently detected, whereas there no amplification with 72 74 nonstreptococcal...
The rhoptry of the malaria parasite Plasmodium falciparum is an unusual secretory organelle that thought to be related lysosomes in higher eukaryotes. Rhoptries contain extensive collection proteins participate host cell invasion and formation parasitophorous vacuole, but little known about sorting signals required for protein targeting. Using green fluorescent chimeras vitro pull-down assays, we performed analysis trafficking RAP1. We provide evidence RAP1 escorted via interaction with...
Malaria parasites are subjected to high levels of oxidative stress during their development inside erythrocytes and the ability parasite defend itself against this assault is critical its survival. Therefore, Plasmodium possesses an effective antioxidant defense system that could potentially be used as a target for inhibitor-based therapy. We have identified unusual peroxiredoxin protein localizes nucleus falciparum renamed it PfnPrx (PF10_0268, earlier called MCP1). Our work reveals has...
Phosphoinositide lipids play key roles in a variety of processes eukaryotic cells, but our understanding their functions the malaria parasite Plasmodium falciparum is still very much limited. To gain deeper comprehension phosphoinositides this important pathogen, we attempted gene inactivation for 24 putative effectors phosphoinositide metabolism. Our results reveal that 79% candidates are refractory to genetic deletion and therefore potentially essential growth. Inactivation coding...
ABSTRACT Dihydroartemisinin-piperaquine (DHA-PPQ), the current frontline artemisinin combination therapy used to treat Plasmodium falciparum malaria in multiple Southeast Asian countries, is now increasingly failing Cambodia, where resistance nearly fixed, which suggests that PPQ has emerged and spreading rapidly Greater Mekong Subregion. Recent reports have shown amplification of genes encoding plasmepsins 2 3 a molecular marker resistance; however, whether these enzymes play role mechanism...
The protozoan parasite Leishmania relies on the uptake of folate and pterin from environment to meet its nutritional requirements. We show here that a novel gene (folate transporter 1 (FT1)) deleted in infantum methotrexate-resistant mutant corresponds main (K(m), 410 nM). FT1 was established as by both transfection targeted deletion. Modulation expression these manipulations altered susceptibility cells methotrexate. Folate transport stage-regulated with higher activity logarithmic phase...
The inner membrane complex and the apical secretory organelles are defining features of apicomplexan parasites. Despite their critical roles, mechanisms behind biogenesis these structures in malaria parasite Plasmodium falciparum still poorly defined. We here show that decreasing expression P. homologue conserved endolysomal escorter Sortilin-VPS10 prevents formation abrogates generation new merozoites. Moreover, protein trafficking to rhoptries, micronemes, dense granules is disrupted,...
Activation of the primary motor cortex (M1) is important for execution skilled movements and learning, its dysfunction contributes to pathophysiology Parkinson's disease (PD). A well-accepted idea in PD research, albeit not tested experimentally, that loss midbrain dopamine leads decreased activation M1 by thalamus. Here, we report altered thalamus input a laminar- cell type-specific fashion induced laminar-specific changes intracortical synaptic transmission. Frequency-dependent dynamics...
The protozoan parasite Leishmania is a folate auxotroph and thus depends on the uptake of from environment to meet its requirement. We show here thatLeishmania contains several putative pteridine transporter genes. Some these genes are deleted in methotrexate-resistantLeishmania cells where there no measurable methotrexate. Transport studies suggest that has more than one active transporter, these, named FT5, corresponds very high affinity (Km 84 nm). both methotrexate was impaired an FT5...
In the remote sensing domain, combination of multi-scale satellite data appears as a new challenge for signal processing community. This approach will lead to strong advances in Earth monitoring and continental land cover classifications by u
The rhoptry organelle is critical for the invasion of an erythrocyte by malaria parasite Plasmodium falciparum. Despite their roles, mechanisms behind biogenesis are still poorly defined. Our earlier work had suggested that interaction between glycosylphosphatidylinositol (GPI)-anchored rhoptry-associated membrane antigen (RAMA) and soluble protein 1 was involved in transport latter from Golgi apparatus to rhoptry. However, how this complex could interact with intracellular trafficking...
Abstract Despite marked reductions in morbidity and mortality the last ten years, malaria still takes a tremendous toll on human populations throughout tropical sub-tropical regions of world. The absence an effective vaccine resistance to most antimalarial drugs available demonstrate urgent need for new intervention strategies. Phosphoinositides are class lipids with critical roles numerous processes their specific subcellular distribution, generated through action kinases phosphatases,...