Elucidating the structure of the mitochondrial genome segregation machinery in trypanosomes by ultrastructure expansion microscopy and cryo-electron tomography

Session

Stream 5: Up Close with the Enemy: Imaging Pathogen-host Dynamics

Authors

Irina Bregy (3), Ana Kalichava (3), Salome Aeschlimann (1), André Schneider (1), Benoît Zuber (2), Torsten Ochsenreiter (3)

Affiliations

1. Department of Chemistry Biochemistry and Pharmaceutical Sciences, University of Bern
2. Institute of Anatomy, University of Bern
3. Institute of Cell Biology, University of Bern

Keywords

Trypanosomes, kDNA, mitochondrial genome, tripartite attachment complex, mitochondrion, ultrastructure expansion microscopy, cry-electron tomography

Abstract text

Trypanosomes belong to the group of Kinetoplastea and are flagellated protozoan parasites that contain a singular mitochondrion with a single unit mitochondrial genome named the kinetoplast DNA (kDNA). Segregation of the genome during cell division is mediated by the basal bodies of the flagellum via the tripartite attachment complex (TAC) that physically connects the basal bodies (aka centrioles) to the kDNA. We characterise the structure and assembly of this megadalton complex using a combination of molecular biology, biochemistry and high resolution imaging. In particular we employ ultrastructure expansion microscopy (U-ExM) and cry-electron tomography to elucidate the arrangement of this complex in situ. 

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