Reductionist Pathways for Parasitism in Euglenozoans? Expanded Datasets Provide New Insights
Genome streamlining and the loss of certain metabolic pathways predate switches to parasitism in the evolution of Euglenozoa and are the result of a multistep process.
Numerous features previously considered trypanosomatid-specific are present also in the free-living euglenozoans. They include nutrient-triggered attachment to surfaces, polycistronic transcription, trans-splicing, trypanothione, the loss of glutathione reductase, genome compaction via almost complete loss of cis-spliced introns, presence and even diversification of surface proteins, subtilisins, and carboxypeptidases.
Rapid sequence evolution in Euglenozoa is not linked to parasitism, as it also occurs in free-living relatives of kinetoplastids.
Butenko A., Hammond M., Field M.C., Ginger M.L., Yurchenko V., Lukeš J. Reductionist Pathways for Parasitism in Euglenozoans? Expanded Datasets Provide New Insights. Trends in parasitology 2021 37: 100–116. DOI: 10.1016/j.pt.2020.10.001.