Article

Centrin gene disruption impairs stage-specific basal body duplication and cell cycle progression in Leishmania.

Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Food and Drug Administration, Bethesda, MD 20892, USA.
Journal of Biological Chemistry (impact factor: 4.77). 07/2004; 279(24):25703-10. DOI:10.1074/jbc.M402794200 pp.25703-10
Source: PubMed

ABSTRACT Centrin is a calcium-binding cytoskeletal protein involved in the duplication of centrosomes in higher eukaryotes. To explore the role of centrin in the protozoan parasite Leishmania, we created Leishmania deficient in the centrin gene (LdCEN). Remarkably, centrin null mutants (LdCEN(-/-)) showed selective growth arrest as axenic amastigotes but not as promastigotes. Flow cytometry analysis confirmed that the mutant axenic amastigotes have a cell cycle arrest at the G(2)/M stage. The axenic amastigotes also showed failure of basal body duplication and failure of cytokinesis resulting in multinucleated "large" cells. Increased terminal deoxy uridine triphosphate nick end labeling positivity was observed in centrin mutant axenic amastigotes compared with wild type cells, suggesting the activation of a programmed cell death pathway. Growth of LdCEN(-/-) amastigotes in infected macrophages in vitro was inhibited and also resulted in large multinucleated parasites. Normal basal body duplication and cell division in the LdCEN knockout promastigote is unique and surprising. Further, this is the first report where disruption of a centrin gene displays stage-specific/cell type-specific failure in cell division in a eukaryote. The centrin null mutant defective in amastigote growth could be useful as a vaccine candidate against leishmaniasis.

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Keywords

amastigote growth
 
axenic amastigotes
 
basal body duplication
 
cell cycle arrest
 
cell division
 
centrin gene
 
centrin gene displays stage-specific/cell type-specific failure
 
centrin mutant axenic amastigotes
 
centrin null mutant defective
 
centrin null mutants
 
Flow cytometry analysis
 
higher eukaryotes
 
large multinucleated parasites
 
LdCEN knockout promastigote
 
mutant axenic amastigotes
 
Normal basal body duplication
 
programmed cell death pathway
 
protozoan parasite Leishmania
 
selective growth arrest
 
wild type cells