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bioRxiv · 10.1101/656165

A single-parasite transcriptional landscape of asexual development in Toxoplasma gondii

Xue, Y.·Theisen, T. C.·Ferrel, A.·Rastogi, S.·Quake, S. R.·Boothroyd, J. C.
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Abstract

Toxoplasma gondii, a protozoan parasite, undergoes a complex and poorly understood developmental process that is critical for establishing a chronic infection in its intermediate hosts. Here, we applied single-cell RNA-sequencing (scRNA-seq) on >5,400 Toxoplasma in both tachyzoite and bradyzoite stages using three widely studied strains to construct a comprehensive atlas of cell-cycle and asexual development, revealing hidden states and transcriptional factors associated with each developmental stage. Analysis of SAG1-related sequence (SRS) antigenic repertoire reveals a highly heterogeneous, sporadic expression pattern unexplained by measurement noise, cell cycle, or asexual development. Furthermore, we identified AP2IX-1 as a transcription factor that controls the switching from the ubiquitous SAG1 to rare surface antigens not previously observed in tachyzoites. In addition, comparative analysis between Toxoplasma and Plasmodium scRNA-seq results reveals concerted expression of gene sets, despite fundamental differences in cell division. Lastly, we built an interactive data-browser for visualization of our atlas resource.

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Xue, Y., Theisen, T. C., Ferrel, A., Rastogi, S., Quake, S. R., Boothroyd, J. C.. 2019-06-03. A single-parasite transcriptional landscape of asexual development in Toxoplasma gondii. https://doi.org/10.1101/656165

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