Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Hard-wiring in the Plasmodium falciparum transcriptome II

ABSTRACT: To help malaria parasites survive unpredictable host immune responses, it is known that genes for surface proteins express stochastically in Plasmodium falciparum. Here, we demonstrate that gene expression for intracellular metabolic functions may be preordained and insensitive to specific metabolic perturbations. In a tightly-controlled, large microarray study involving over 100 hybridizations to isogenic drug-sensitive and drug-resistant parasites, the lethal antifolate WR99210 failed to over-produce RNA for the biochemically and genetically proven target dihydrofolate reductase-thymidylate synthase (DHFR-TS). Beyond the target, this transcriptional obstinacy carried over to the rest of the parasite genome, including genes for target pathways of folate and pyrimidine metabolism. Even 12 hours after commitment to death, the transcriptome remained faithful to evolutionarily entrained paths. A system-wide transcriptional disregard for metabolic perturbations in malaria parasites may contribute to selective vulnerabilities of the parasite to lethal antimetabolites. While large protective metabolic responses were not detected, DNA microarrays helped capture small, but reproducible drug-dependent perturbations within hours of drug exposure. In addition, in Plasmodium cells that had adapted to long-term drug exposure, DNA microarrays revealed new, large genome-wide transcriptional adjustments in the hard-wired transcriptional program itself. Keywords: Plasmodium falciparum treated with pyrimethamine RNA from pyrimethamine-treated parasite vs RNA from untreated control, Pyr-sensitive TM4/8.2 parasite strain, pyrimethamine concentration at IC50 and treated for 2 h, 4 h, and 8 h, microarray data were obtained from at least four hybridizations using RNA from at least two independent parasite cultures

ORGANISM(S): Plasmodium falciparum

SUBMITTER: Joseph Fowble

PROVIDER: E-GEOD-9868 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:Control of malaria is threatened by emerging parasite resistance to artemisinin drug (ART) therapies. The molecular details of how Plasmodium malaria parasites response to ART and how this relates to resistance is not clear. To determine how parasites respond to ART by altering gene expression, we performed a transcriptomic study of dihydroartemisinin (DHA) response in P. falciparum K1 strain and in P. berghei ANKA strain. Microarray data from DHA-treated P. falciparum trophozoite stage parasites were compared with data from other ART treatments. Genes with consistent changes in expression were identified, which includes notably down-regulation of cytosolic ribosomal protein genes. RNA-seq data revealed a similar pattern of transcriptomic change, although the pattern was much clearer in that more than one-third of P. falciparum trophozoite genes are differentially expressed with greater statistical support for down-regulation of ribosomal protein genes. The poor overlap of differentially-expressed genes between microarray and RNA-seq and less-well defined patterns for the former suggests that the accuracy of microarray is limited by technological bias. The trophozoite response to DHA is overall âring-likeâ and less âtrophozoite-likeâ, which is consistent with previous findings that Plasmodium can enter a quiescent ring-like state to resist ART. RNA-seq data from DHA-treated P. falciparum rings reveal a more muted response, although there is considerable overlap of differentially expressed genes with DHA-treated trophozoites. In contrast, P. falciparum schizonts are unresponsive to DHA, suggesting that the protective response acts mainly to arrest parasite development through the G2/M checkpoint. The transcriptional response of P. berghei to DHA treatment in vivo in infected mice is strikingly similar to the P. falciparum in vitro ring and trophozoite responses, in which ribosomal protein genes are notably down-regulated. These results suggest Plasmodium species respond to DHA in the same way. This knowledge could be applied to outwit the parasite to deliver more effective artemisinin therapies, and maybe hinder the development of drug resistance. Two condition drug-treatment experiment, Dihydroartemisinin vs. Vehicle control treatment with matched reference untreated controls. Biological replicates: 5 independently grown and harvested experimental culture replicates. One replicate of treatment/reference time-point per array.

Dataset Information

Hard-wiring in the Plasmodium falciparum transcriptome II

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets