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Gene encoding a deubiquitinating enzyme is mutated in artesunate- and chloroquine-resistant rodent malaria parasites§

Artemisinin- and artesunate-resistant Plasmodium chabaudi mutants, AS-ART and AS-ATN, were previously selected from chloroquine-resistant clones AS-30CQ and AS-15CQ respectively. Now, a genetic cross between AS-ART and the artemisinin-sensitive clone AJ has been analysed by Linkage Group Selection....

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Detalles Bibliográficos
Autores principales: Hunt, Paul, Afonso, Ana, Creasey, Alison, Culleton, Richard, Sidhu, Amar Bir Singh, Logan, John, Valderramos, Stephanie G, McNae, Iain, Cheesman, Sandra, do Rosario, Virgilio, Carter, Richard, Fidock, David A, Cravo, Pedro
Formato: Texto
Lenguaje:English
Publicado: Blackwell Publishing Ltd 2007
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1974797/
https://www.ncbi.nlm.nih.gov/pubmed/17581118
http://dx.doi.org/10.1111/j.1365-2958.2007.05753.x
Descripción
Sumario:Artemisinin- and artesunate-resistant Plasmodium chabaudi mutants, AS-ART and AS-ATN, were previously selected from chloroquine-resistant clones AS-30CQ and AS-15CQ respectively. Now, a genetic cross between AS-ART and the artemisinin-sensitive clone AJ has been analysed by Linkage Group Selection. A genetic linkage group on chromosome 2 was selected under artemisinin treatment. Within this locus, we identified two different mutations in a gene encoding a deubiquitinating enzyme. A distinct mutation occurred in each of the clones AS-30CQ and AS-ATN, relative to their respective progenitors in the AS lineage. The mutations occurred independently in different clones under drug selection with chloroquine (high concentration) or artesunate. Each mutation maps to a critical residue in a homologous human deubiquitinating protein structure. Although one mutation could theoretically account for the resistance of AS-ATN to artemisinin derivates, the other cannot account solely for the resistance of AS-ART, relative to the responses of its sensitive progenitor AS-30CQ. Two lines of Plasmodium falciparum with decreased susceptibility to artemisinin were also selected. Their drug-response phenotype was not genetically stable. No mutations in the UBP-1 gene encoding the P. falciparum orthologue of the deubiquitinating enzyme were observed. The possible significance of these mutations in parasite responses to chloroquine or artemisinin is discussed.