title: Patterns of organelle ontogeny through a cell cycle revealed by whole-cell reconstructions using 3D electron microscopy.
abstract: The major mammalian bloodstream form of the African sleeping sickness parasite Trypanosoma brucei multiplies rapidly, and it is important to understand how these cells divide. Organelle inheritance involves complex spatiotemporal re-arrangements to ensure correct distribution to daughter cells. Here, serial block face scanning electron microscopy (SBF-SEM) was used to reconstruct whole individual cells at different stages of the cell cycle to give an unprecedented temporal, spatial and quantitative view of organelle division, inheritance and abscission in a eukaryotic cell. Extensive mitochondrial branching occurred only along the ventral surface of the parasite, but the mitochondria returned to a tubular form during cytokinesis. Fission of the mitochondrion occurred within the cytoplasmic bridge during the final stage of cell division, correlating with cell abscission. The nuclei were located underneath each flagellum at mitosis and the mitotic spindle was located along the ventral surface, further demonstrating the asymmetric arrangement of cell cleavage in trypanosomes. Finally, measurements demonstrated that multiple Golgi bodies were accurately positioned along the flagellum attachment zone, suggesting a mechanism for determining the location of Golgi bodies along each flagellum during the cell cycle.
authors.affiliation: Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford OX3 0BP, UK.
authors.forename: Louise
authors.initials: L
authors.lastname: Hughes
authors.affiliation: Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford OX3 0BP, UK.
authors.forename: Samantha
authors.identifier: 0000-0003-4292-858X
authors.initials: S
authors.lastname: Borrett
authors.affiliation: Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford OX3 0BP, UK.
authors.forename: Katie
authors.identifier: 0000-0001-9187-8027
authors.initials: K
authors.lastname: Towers
authors.affiliation: Wellcome Centre for Cell Matrix Research, University of Manchester, Michael Smith Building, Manchester M13 9PT, UK.
authors.forename: Tobias
authors.initials: T
authors.lastname: Starborg
authors.affiliation: Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford OX3 0BP, UK svaughan@brookes.ac.uk.
authors.forename: Sue
authors.identifier: 0000-0002-0925-4491
authors.initials: S
authors.lastname: Vaughan
mesh_terms: D002453:Cell Cycle; D002467:Cell Nucleus / Q000378:metabolism / Q000648:ultrastructure; D005407:Flagella / Q000378:metabolism / Q000648:ultrastructure; D006056:Golgi Apparatus / Q000378:metabolism / Q000648:ultrastructure; D021621:Imaging, Three-Dimensional; D008855:Microscopy, Electron, Scanning / Q000379:methods*; D008928:Mitochondria / Q000378:metabolism / Q000648:ultrastructure; D063154:Mitochondrial Dynamics; D008954:Models, Biological; D015388:Organelles / Q000378:metabolism* / Q000648:ultrastructure*; D014346:Trypanosoma brucei brucei / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure*
keywords: Abscission; Acidocalcisome; Flagellum; Glycosome; Golgi body; Kinetoplast; Mitochondrion; Organelle inheritance; SBF-SEM