Characterization and tissue-specific expression patterns of the Plasmodium chabaudi cir multigene family

Abstract Background Variant antigens expressed on the surface of parasitized red blood cells (pRBCs) are important virulence factors of malaria parasites. Whereas Plasmodium falciparum erythrocyte membrane proteins 1 (PfEMP1) are responsible for sequestration of mature parasites, little is known abo...

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Bibliographic Details
Published in:Malaria Journal
Main Authors: Krücken Jürgen, Ebbinghaus Petra
Format: Article in Journal/Newspaper
Language:English
Published: BMC 2011
Subjects:
Online Access:https://doi.org/10.1186/1475-2875-10-272
https://doaj.org/article/50ac72e7339e4ea6ac05e1b70f0adce3
Description
Summary:Abstract Background Variant antigens expressed on the surface of parasitized red blood cells (pRBCs) are important virulence factors of malaria parasites. Whereas Plasmodium falciparum erythrocyte membrane proteins 1 (PfEMP1) are responsible for sequestration of mature parasites, little is known about putative ligands mediating cytoadherence to host receptors in other Plasmodium species. Candidates include members of the pir superfamily found in the human parasite Plasmodium vivax ( vir ), in the simian pathogen Plasmodium knowlesi ( kir ) and in the rodent malarias Plasmodium yoelii ( yir ), Plasmodium berghei ( bir ) and Plasmodium chabaudi ( cir ). The aim of this study was to reveal a potential involvement of cir genes in P. chabaudi sequestration. Methods Subfamilies of cir genes were identified by bioinformatic analyses of annotated sequence data in the Plasmodium Genome Database. In order to examine tissue-specific differences in the expression of cir mRNAs, RT-PCR with subfamily-specific primers was used. In total, 432 cDNA clones derived from six different tissues were sequenced to characterize the transcribed cir gene repertoire. To confirm differences in transcription profiles of cir genes, restriction fragment length polymorphism (RFLP) analyses were performed to compare different host tissues and to identify changes during the course of P. chabaudi infections in immunocompetent mice. Results The phylogenetic analysis of annotated P. chabaudi putative CIR proteins identified two major subfamilies. Comparison of transcribed cir genes from six different tissues revealed significant differences in the frequency clones belonging to individual cir gene subgroups were obtained from different tissues. Further hints of difference in the transcription of cir genes in individual tissues were obtained by RFLP. Whereas only minimal changes in the transcription pattern of cir genes could be detected during the developmental cycle of the parasites, switching to expression of other cir genes during the course of an ...