Antigenic diversity in malaria parasites is maintained on extrachromosomal DNA

Ebel, E. R.; Kim, B. Y.; McDew-White, M.; Egan, E. S.; Anderson, T. J.; Petrov, D. A.

doi:10.1101/2023.02.02.526885

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bioRxiv · 10.1101/2023.02.02.526885

Antigenic diversity in malaria parasites is maintained on extrachromosomal DNA

Ebel, E. R.·Kim, B. Y.·McDew-White, M.·Egan, E. S.·Anderson, T. J.·Petrov, D. A.

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Abstract

Sequence variation among antigenic var genes enables Plasmodium falciparum malaria parasites to evade host immunity. Using long sequence reads from haploid clones from a mutation accumulation experiment, we detect var diversity inconsistent with simple chromosomal inheritance. We discover putatively circular DNA that is strongly enriched for var genes, which exist in multiple alleles per locus separated by recombination and indel events. Extrachromosomal DNA likely contributes to rapid antigenic diversification in P. falciparum.

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Ebel, E. R., Kim, B. Y., McDew-White, M., Egan, E. S., Anderson, T. J., Petrov, D. A.. 2023-02-02. Antigenic diversity in malaria parasites is maintained on extrachromosomal DNA. https://doi.org/10.1101/2023.02.02.526885

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