Project description:Periodic fever is the most characteristic clinical feature of human malaria. However, how parasites survive malarial febrile episodes, which often involve temperatures of >40ºC, is not known. Plasmodium falciparum cultures adapted to periodic heat shock were used to identify PfAP2-HS as a transcription factor that is essential for survival at febrile temperatures. Transcriptomic analysis was performed to compare the effect of heat shock in parasites presenting the wild type form of PfAP2-HS (10E) and parasites that have defects in this protein, either a premature stop codon mutation (10G) or the deletion of the entire pfap2-hs gene (10E_pfap2-hs). A timecourse analysis including samples taken before, during and after heat shock revealed that the initial phase of the PfAP2-HS-dependent response is largely restricted to hsp70-1 and hsp90.
Project description:Periodic fever is the most characteristic clinical feature of human malaria. However, how parasites survive malarial febrile episodes, which often involve temperatures of >40ºC, is not known. To understand the molecular basis of heat shock (HS) resistance in Plasmodium falciparum, we took advantage of previously developed P. falciparum lines adapted to periodic HS (3D7-A-HS) and their non-selected controls maintained in parallel (3D7-A). Their ability to adapt in only a few cycles suggested that the parental parasite population contained a selectable subset of parasites resistant to HS. Transcriptomic analysis of both 3D7-A-HS and 3D7-A was used to study the differences at a transcriptional level that could be related with the HS-resistant phenotype.
Project description:This SuperSeries is composed of the following subset Series: GSE25878: Artemisinin resistance in Plasmodium falciparum is associated with an altered temporal pattern of transcription (expression) GSE25879: Artemisinin resistance in Plasmodium falciparum is associated with an altered temporal pattern of transcription (CGH) Refer to individual Series
Project description:This project investigates changes in protein phosphorylation in the malaria parasite Plasmodium falciparum in response to heat stress. During infection parasites are exposed to febrile temperatures in the human host. Heat stress is known to trigger adaptive responses but the role of protein phosphorylation in this process is not fully understood. The aim of this study is to identify phosphorylation events that change following exposure to elevated temperature. Synchronous asexual blood stage parasites were exposed to heat stress and compared with parasites maintained at normal culture temperature. Parasites were harvested after heat stress and proteins were extracted and digested into peptides. Phosphopeptides were enriched prior to analysis by liquid chromatography coupled to tandem mass spectrometry. The resulting data provide a global view of phosphorylation changes associated with heat stress in P. falciparum. This dataset enables the identification of heat responsive phosphosites and supports analysis of signalling pathways and regulatory processes that may contribute to parasite adaptation to febrile conditions.
Project description:Transcriptomic Analysis of Cultured Sporozoites of P. falciparum RNA-seq reads from each of three developmental stages (2 replicates per sample) were mapped to the reference Plasmodium falciparum genome, and gene expression levels were calculated for each sample.