title: Mitochondrial growth during the cell cycle of Trypanosoma brucei bloodstream forms.
abstract: Mitochondrial organelles need to be replicated during cell division. Many aspects of this process have been studied in great detail, however the actual size increase and the position of organelle growth are less well understood. We use the protozoan parasite Trypanosoma brucei that contains a single mitochondrion to study organelle biogenesis by fluorescence microscopy. From the analysis of more than 1000 T. brucei bloodstream form cells of a nonsynchronous population we conclude that the mitochondrial network mostly grows from two areas along the main organelle axis, posterior and anterior of the nucleus. Loops and branches from these two areas eventually fuse to build a complex network. Together with the appearance of the division fold in the posterior part of the cell, pruning of the mitochondrial network and finally separation into the two daughter cells occurs. Overall organelle biogenesis is not continuous during cell growth and occurs mostly in the last part of the cell cycle. Furthermore, using 3D STED super resolution microscopy we reconstruct the volume of the organelle and characterize the region where the mitochondrial genome is positioned by serial block face scanning electron microscopy.
authors.affiliation: Institute of Cell Biology, University of Bern, Switzerland.
authors.forename: Martin
authors.initials: M
authors.lastname: Jakob
authors.affiliation: Institute of Cell Biology, University of Bern, Switzerland.|Graduate School for Cellular and Biomedical Sciences, University of Bern, Switzerland.
authors.forename: Anneliese
authors.initials: A
authors.lastname: Hoffmann
authors.affiliation: Institute of Cell Biology, University of Bern, Switzerland.|Graduate School for Cellular and Biomedical Sciences, University of Bern, Switzerland.
authors.forename: Simona
authors.initials: S
authors.lastname: Amodeo
authors.affiliation: Graduate School for Cellular and Biomedical Sciences, University of Bern, Switzerland.|Institute of Anatomy, University of Bern, Switzerland.
authors.forename: Camille
authors.initials: C
authors.lastname: Peitsch
authors.affiliation: Institute of Anatomy, University of Bern, Switzerland.
authors.forename: Benoît
authors.initials: B
authors.lastname: Zuber
authors.affiliation: Institute of Cell Biology, University of Bern, Switzerland.
authors.forename: Torsten
authors.initials: T
authors.lastname: Ochsenreiter
mesh_terms: D002453:Cell Cycle / Q000502:physiology*; D008928:Mitochondria / Q000502:physiology*; D063154:Mitochondrial Dynamics / Q000502:physiology*; D014346:Trypanosoma brucei brucei / Q000166:cytology / Q000378:metabolism*