Comparative transcriptomics reveal differential gene expression among Plasmodium vivax geographical isolates and implications on erythrocyte invasion mechanisms

International audience The documentation of Plasmodium vivax malaria across Africa especially in regions where Duffy negatives are dominant suggests possibly alternative erythrocyte invasion mechanisms. While the transcriptomes of the Southeast Asian and South American P . vivax are well documented, the gene expression profile of P . vivax in Africa is unclear. In this study, we examined the expression of 4,404 gene transcripts belong to 12 functional groups and 43 erythrocyte binding gene candidates in Ethiopian isolates and compared them with the Cambodian and Brazilian P . vivax transcriptomes. Overall, there were 10–26% differences in the gene expression profile amongst geographical isolates, with the Ethiopian and Cambodian P . vivax being most similar. Majority of the gene transcripts involved in protein transportation, housekeeping, and host interaction were highly transcribed in the Ethiopian isolates. Members of the reticulocyte binding protein PvRBP 2a and PvRBP 3 expressed six-fold higher than Duffy binding protein PvDBP 1 and 60-fold higher than PvEB P/ DBP 2 in the Ethiopian isolates. Other genes including PvMSP3 . 8 , PvMSP3 . 9 , PvTRAG2 , PvTRAG14 , and PvTRAG22 also showed relatively high expression. Differential expression patterns were observed among geographical isolates, e.g., PvDBP 1 and PvEB P/ DBP 2 were highly expressed in the Cambodian but not the Brazilian and Ethiopian isolates, whereas PvRBP 2a and PvRBP 2b showed higher expression in the Ethiopian and Cambodian than the Brazilian isolates. Compared to Pvs 25, gametocyte genes including PvAP2-G , PvGAP (female gametocytes), and Pvs 47 (male gametocytes) were highly expressed across geographical samples.