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bioRxiv · 10.1101/2023.08.09.552632

Comparative proteomics uncovers correlation between tRip-mediated host tRNA import and asparagine insertion in Plasmodium proteins

Pitolli, M.·Cela, M.·Kapps, D.·Chicher, J.·Despons, L.·Frugier, M.
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Abstract

tRNAs are not only essential for decoding the genetic code, but their abundance also has a strong impact on the rate of protein production, folding, and on the stability of the translated messenger RNAs. Plasmodium expresses a unique surface protein called tRip, involved in the import of exogenous tRNAs into the parasite. Comparative proteomic analysis of the blood stage of wild-type and tRip-KO variant of P. berghei parasites revealed that down-regulated proteins in the mutant parasite are distinguished by a bias in their asparagine content. Furthermore, the demonstration of the possibility of charging host tRNAs with Plasmodium aminoacyl-tRNA synthetases, led us to propose that, imported host tRNAs participate in parasite protein synthesis. These results also suggest a novel mechanism of translational control in which import of host tRNAs emerge as regulators of gene expression in the Plasmodium developmental cycle and pathogenesis, by enabling the synthesis of asparagine-rich regulatory proteins that efficiently and selectively control the parasite infectivity.

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Pitolli, M., Cela, M., Kapps, D., Chicher, J., Despons, L., Frugier, M.. 2023-08-09. Comparative proteomics uncovers correlation between tRip-mediated host tRNA import and asparagine insertion in Plasmodium proteins. https://doi.org/10.1101/2023.08.09.552632

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