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bioRxiv · 10.1101/2021.04.20.440568

Ultrastructure Expansion Microscopy in Trypanosoma brucei

Kalichava, A.·Ochsenreiter, T.
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Abstract

Abstract-IntroductionThe recently developed ultrastructure expansion microscopy (U-ExM) technique allows to increase the spatial resolution within a cell or tissue for microscopic imaging through the physical expansion of the sample. In this study we validate the use of U-ExM in Trypanosoma brucei by visualizing the nucleus and kDNA as well as proteins of the cytoskeleton, the basal body, the mitochondrion and the ER. T. brucei is a unicellular flagellated protozoan parasite and the causative agent of human African sleeping sickness and Nagana in cattle.The highly polarized parasite cell body is about 25 m in length and is shaped by the subpellicular microtubule corset. Its single flagellum emanates from the posterior part of the cell and is attached along the entire cell body. T. brucei The cell contains all typical organelles of eukaryotic cells including ER, Golgi and mitochondrion. Interestingly, Golgi and mitochondrion are single unit organelles in this protozoan parasite. The signature feature of trypanosomes is the single unit mitochondrial genome, the kinetoplast DNA (kDNA) that is organized in a complex structure of interlocked mini- and maxicircles. The kDNA is segregated during cell division by the tripartite attachment complex (TAC) that connects it via the mitochondrial membranes to the base of the flagellum.

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Kalichava, A., Ochsenreiter, T.. 2021-04-20. Ultrastructure Expansion Microscopy in Trypanosoma brucei. https://doi.org/10.1101/2021.04.20.440568

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