CGH of Plasmodium falciparum selected with DSM1
Ontology highlight
ABSTRACT:
ORGANISM(S): Plasmodium falciparum
PROVIDER: GSE37306 | GEO | 2013/05/01
SECONDARY ACCESSION(S): PRJNA159419
REPOSITORIES: GEO
Similar Datasets
Project description:Continual challenge of 107 ARMD Dd2 parasites with 0.3µM DSM1, a novel dihydroorotate dehydrogenase (DHODH) inhibitor, reproducibly generated ~5-fold resistance and 3-fold amplification of 30-100Kb DNA, always including the DHODH gene. Subsequent 3-10µM DSM-1 pressure selected for ~10-fold amplification of the copy number variant (CNV), and over 100-fold resistance. Target-specific and genome-wide DNA sequencing revealed no additional mutations contributing to DSM1 resistance. Each DSM1-resistant clone is compared to the Dd2 parent reference sample.
2013-05-01 | E-GEOD-37306 | biostudies-arrayexpress
Project description:While many molecular changes associated with commonly used antimalarials are known, there remain important questions on how parasites arrive at the correct causal molecular solutions in a haploid genome. We selected for resistance to DSM1, a novel dihydroorotate dehydrogenase (DHODH) inhibitor with a non-biological triazolopyrimidine scaffold, in P. falciparum with the Accelerated Resistance to Multiple Drugs (ARMD) trait. While direct sequencing revealed no mutations in the target DHODH gene, comparative genomic hybridizations from four independently selected DSM1-resistant clones showed a large, single 34-95kb amplification in each clone. Each amplified region always included the DHODH locus. The length of this region and the resulting 2- to 3-fold DHODH copy number increase were verified at the RNA and protein level. DSM1 resistance was stable over several months of in vitro culture. Additional selection at higher DSM1 concentrations caused further gains in CNVs at the DHODH locus. The present system validated DHODH as a key target of the triazolopyrimidine antimalarial, DSM1 and, more importantly, captured large, random CNVs as an early step in the initiation of drug resistance in malaria parasites. This defined system is expected to be valuable for characterizing early, causal molecular steps leading to successful drug resistance gDNA from P. falciparum DSM1 resistant cell-line was hybridized against gDNA of parental strain, Dd2. DSM1 resistant cell culture was maintained under DSM1 at 333 nM, microarray data were obtained from three hybridizations using gDNA from three independent parasite cultures
2013-05-01 | E-GEOD-35732 | biostudies-arrayexpress
Project description:While many molecular changes associated with commonly used antimalarials are known, there remain important questions on how parasites arrive at the correct causal molecular solutions in a haploid genome. We selected for resistance to DSM1, a novel dihydroorotate dehydrogenase (DHODH) inhibitor with a non-biological triazolopyrimidine scaffold, in P. falciparum with the Accelerated Resistance to Multiple Drugs (ARMD) trait. While direct sequencing revealed no mutations in the target DHODH gene, comparative genomic hybridizations from four independently selected DSM1-resistant clones showed a large, single 34-95kb amplification in each clone. Each amplified region always included the DHODH locus. The length of this region and the resulting 2- to 3-fold DHODH copy number increase were verified at the RNA and protein level. DSM1 resistance was stable over several months of in vitro culture. Additional selection at higher DSM1 concentrations caused further gains in CNVs at the DHODH locus. The present system validated DHODH as a key target of the triazolopyrimidine antimalarial, DSM1 and, more importantly, captured large, random CNVs as an early step in the initiation of drug resistance in malaria parasites. This defined system is expected to be valuable for characterizing early, causal molecular steps leading to successful drug resistance RNA from P. falciparum DSM1 resistant cell-line was hybridized against RNA of parental strain, Dd2. DSM1 resistant cell culture was maintained under DSM1 at 333 nM, microarray data were obtained from three hybridizations using RNA from three independent parasite cultures
2013-05-01 | E-GEOD-35949 | biostudies-arrayexpress
Project description:While many molecular changes associated with commonly used antimalarials are known, there remain important questions on how parasites arrive at the correct causal molecular solutions in a haploid genome. We selected for resistance to DSM1, a novel dihydroorotate dehydrogenase (DHODH) inhibitor with a non-biological triazolopyrimidine scaffold, in P. falciparum with the Accelerated Resistance to Multiple Drugs (ARMD) trait. While direct sequencing revealed no mutations in the target DHODH gene, comparative genomic hybridizations from four independently selected DSM1-resistant clones showed a large, single 34-95kb amplification in each clone. Each amplified region always included the DHODH locus. The length of this region and the resulting 2- to 3-fold DHODH copy number increase were verified at the RNA and protein level. DSM1 resistance was stable over several months of in vitro culture. Additional selection at higher DSM1 concentrations caused further gains in CNVs at the DHODH locus. The present system validated DHODH as a key target of the triazolopyrimidine antimalarial, DSM1 and, more importantly, captured large, random CNVs as an early step in the initiation of drug resistance in malaria parasites. This defined system is expected to be valuable for characterizing early, causal molecular steps leading to successful drug resistance
2013-05-01 | GSE35949 | GEO
Project description:While many molecular changes associated with commonly used antimalarials are known, there remain important questions on how parasites arrive at the correct causal molecular solutions in a haploid genome. We selected for resistance to DSM1, a novel dihydroorotate dehydrogenase (DHODH) inhibitor with a non-biological triazolopyrimidine scaffold, in P. falciparum with the Accelerated Resistance to Multiple Drugs (ARMD) trait. While direct sequencing revealed no mutations in the target DHODH gene, comparative genomic hybridizations from four independently selected DSM1-resistant clones showed a large, single 34-95kb amplification in each clone. Each amplified region always included the DHODH locus. The length of this region and the resulting 2- to 3-fold DHODH copy number increase were verified at the RNA and protein level. DSM1 resistance was stable over several months of in vitro culture. Additional selection at higher DSM1 concentrations caused further gains in CNVs at the DHODH locus. The present system validated DHODH as a key target of the triazolopyrimidine antimalarial, DSM1 and, more importantly, captured large, random CNVs as an early step in the initiation of drug resistance in malaria parasites. This defined system is expected to be valuable for characterizing early, causal molecular steps leading to successful drug resistance
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