Characterization and gene expression analysis of the cir multi-gene family of Plasmodium chabaudi chabaudi (AS)
Ontology highlight
ABSTRACT: The pir genes comprise the largest multi-gene family in Plasmodium, with members found in P. vivax, P. knowlesi and the rodent malaria species. Despite comprising up to 5% of the parasite genome, little is known about the functions of the proteins encoded by pir genes. P. chabaudi causes chronic infection in mice, which may be due antigenic variation. In this model, pir genes are called cirs and may be involved in this mechanism allowing evasion of host immune responses. We have annotated the cir repertoire and performed detailed bioinformatic characterization of the encoded CIR proteins. Two major sub-families were identified: A and B, which display different amino acid motifs, and are thus predicted to have undergone functional divergence. The expression of all cirs was analyzed via RNA sequencing and microarray. Up to 40% of cir genes were expressed in the parasite population during infection, including members of both sub-families. Dominant cir transcripts could also be identified. Finally, specific cir genes were expressed at different time points during the blood stages of infection. Together our data characterizing the cir genes and their expression throughout the intra-erythrocytic cycle of development indicate that CIR proteins are likely to be important for parasite survival in the host. P. chabaudi AS is a highly synchronous parasite for which development in the blood follows its hostM-bM-^@M-^Ys circadian rhythm. Twelve time-points were then collected; one every two hours, to cover the entire 24 h cycle of blood stage development. At the peak of parasitaemia, one mouse was sacrificed at each time point and thin blood films were made and stained with Giemsa for optical microscopy. The pan-rodent microarray was designed using the OligoRankPick program as previously described: Liew, K et al.2010, Defining species specific genome differences in malaria parasites. BMC genomics 11,128. The RNA preparation, Cy-dye coupling to cDNA, hybridization and slide scanning were performed as described by Bozdech and colleagues Bozdech, Z et al 2003, The transcriptome of the intraerythrocytic developmental cycle of Plasmodium falciparum. PLoS Biol 1, E5.
ORGANISM(S): Plasmodium chabaudi chabaudi
SUBMITTER: Peter Preiser
PROVIDER: E-GEOD-33333 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
ACCESS DATA