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bioRxiv · 10.1101/2021.10.12.464051

Localization of the putative recombinase Pf-int to the apicoplast of Plasmodium falciparum

Berglar, A. V.·Vembar, S. S.·Gopaul, D. N.
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Abstract

Diseases caused by apicomplexan parasites, such as malaria and toxoplasmosis cause [~]200 million (worldwide) and 1 million (Europe) infections, respectively, every year. Apicomplexa possess a non-photosynthetic organelle homologous to the plant chloroplast, the so-called apicoplast, that is essential for their growth and survival. This study focused on the Int recombinase, the first protein discovered in Plasmodium spp. with the features of a site-specific recombinase, and which has an apicoplast targeting leader sequence at its amino-terminus. Int is conserved amongst several apicomplexan parasites. In the human toxoplasmosis parasite, Toxoplasma, Int localizes to the apicoplast and Pf-Int, the P. falciparum member, belongs to the group of non-mutable essential genes in P. falciparum. A conserved protein that has been shown to be essential at least in one species and that localizes to an essential organelle may become a novel drug target. Therefore, the aim of this study was to confirm the sub-cellular localization of Int in the human malaria parasite P. falciparum. Using western blot analysis and immunofluorescence microscopy of P. falciparum asexual blood stages, we observed that Int partially co-localized with the apicoplast (to discrete foci adjacent to the nucleus).

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Berglar, A. V., Vembar, S. S., Gopaul, D. N.. 2021-10-12. Localization of the putative recombinase Pf-int to the apicoplast of Plasmodium falciparum. https://doi.org/10.1101/2021.10.12.464051

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