Profiling the bloodstream form and procyclic form Trypanosoma brucei cell cycle using single cell transcriptomics
- University of Edinburgh, United Kingdom
- University of Glasgow, United Kingdom
Abstract
African trypanosomes proliferate as bloodstream forms and procyclic forms in the mammal and tsetse fly midgut, respectively. This allows them to colonise the host environment upon infection and ensure life cycle progression. Yet, understanding of the mechanisms that regulate and drive the cell replication cycle of these forms is limited. Using single cell transcriptomics on unsynchronised cell populations, we have obtained high resolution cell cycle regulated transcriptomes of both procyclic and slender bloodstream form Trypanosoma brucei without prior cell sorting or synchronisation. Additionally, we describe an efficient freeze-thawing protocol that allows single cell transcriptomic analysis of cryopreserved T. brucei. Computational reconstruction of the cell cycle using periodic pseudotime inference allowed the dynamic expression patterns of cycling genes to be profiled for both life cycle forms. Comparative analyses identify a core cycling transcriptome highly conserved between forms, as well as several genes where transcript levels dynamics are form-specific. Comparing transcript expression patterns with protein abundance revealed that the majority of genes with periodic cycling transcript and protein levels exhibit a relative delay between peak transcript and protein expression. This work reveals novel detail of the cell cycle regulated transcriptomes of both forms, which are available for further interrogation via an interactive webtool.
Data availability
The transcriptome data generated in this study have been deposited in the EuropeanNucleotide Archive with project accession number PRJEB58781. The processed transcript count data and cell metadata generated in this study are available at Zenodo (10.5281/zenodo.7508131). BSF and PCF cell cycle transcriptomes can also explored using the interactive cell atlas (https://cellatlas-cxg.mvls.gla.ac.uk/Tbrucei.cellcycle.bsf/ and https://cellatlas-cxg.mvls.gla.ac.uk/Tbrucei.cellcycle.pcf/).
Article and author information
Author details
Catarina A Marques
Funding
Wellcome Trust (218648/Z/19/Z)
- Emma M Briggs
Wellcome Trust (104111/Z/14/ZR)
- Thomas D Otto
Wellcome Trust (221717/Z/20/Z)
- Keith R Matthews
Wellcome Trust (220058/Z/19/Z)
- Guy R Oldrieve
- Keith R Matthews
Biotechnology and Biological Sciences Research Council (BB/R017166/1)
- Catarina A Marques
Biotechnology and Biological Sciences Research Council (BB/W001101/1)
- Catarina A Marques
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Briggs 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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Profiling the bloodstream form and procyclic form Trypanosoma brucei cell cycle using single cell transcriptomics
eLife 12:e86325.
https://doi.org/10.7554/eLife.86325
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