Apicomplexan-like parasites are polyphyletic and widely but selectively dependent on cryptic plastid organelles
- University College London, United Kingdom
- Saint Petersburg State University, Russian Federation
- Lomonosov Moscow State University, Russian Federation
Abstract
The phylum Apicomplexa comprises human pathogens such as Plasmodium but are also an under-explored hotspot of evolutionary diversity central to understanding the origins of parasitism and non-photosynthetic plastids. We generated single-cell transcriptomes for all major apicomplexan groups lacking large-scale sequence data. Phylogenetic analysis reveals that apicomplexan-like parasites are polyphyletic and their similar morphologies emerged convergently at least three times. Gregarines and eugregarines are monophyletic, against most expectations, and rhytidocystids and Eleutheroschizon are sister lineages to medically important taxa. Although previously unrecognized, plastids in deep-branching apicomplexans are common, and they contain some of the most divergent and AT-rich genomes ever found. In eugregarines, however, plastids are either abnormally reduced or absent, thus increasing known plastid losses in eukaryotes from two to four. Environmental sequences of ten novel plastid lineages and structural innovations in plastid proteins confirm that plastids in apicomplexans and their relatives are widespread and share a common, photosynthetic origin.
Data availability
Sequence data have been deposited in NCBI under the Bioproject accessions PRJNA557242 and PRJNA556465. Sources of data for individual analyses are provided in Supplemental Tables S1 to S7.
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Transcriptomes of apicomplexan parasitesNCBI Bioproject, PRJNA557242.
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Transcriptome of Digyalum oweniNCBI Bioproject, PRJNA556465.
Article and author information
Author details
Vladimir V Aleoshin
Funding
University College London (Excellence Research Fellowship)
- Jan Janouškovec
Russian Foundation for Basic Research (18-04-00324)
- Gita G Paskerova
- Timur G Simdyanov
Russian Science Foundation (18-04-00123)
- Vladimir V Aleoshin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- John McCutcheon, University of Montana
Version history
- Received: June 25, 2019
- Accepted: August 14, 2019
- Accepted Manuscript published: August 16, 2019 (version 1)
- Version of Record published: September 9, 2019 (version 2)
- Version of Record updated: September 10, 2019 (version 3)
Copyright
© 2019, Janouškovec et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Apicomplexan-like parasites are polyphyletic and widely but selectively dependent on cryptic plastid organelles
eLife 8:e49662.
https://doi.org/10.7554/eLife.49662
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