@article{SchusterKruegerSubotaetal.2017, author = {Schuster, Sarah and Kr{\"u}ger, Timothy and Subota, Ines and Thusek, Sina and Rotureau, Brice and Beilhack, Andreas and Engstler, Markus}, title = {Developmental adaptations of trypanosome motility to the tsetse fly host environments unravel a multifaceted in vivo microswimmer system}, series = {eLife}, volume = {6}, journal = {eLife}, doi = {10.7554/eLife.27656}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158662}, pages = {e27656}, year = {2017}, abstract = {The highly motile and versatile protozoan pathogen Trypanosoma brucei undergoes a complex life cycle in the tsetse fly. Here we introduce the host insect as an expedient model environment for microswimmer research, as it allows examination of microbial motion within a diversified, secluded and yet microscopically tractable space. During their week-long journey through the different microenvironments of the fly´s interior organs, the incessantly swimming trypanosomes cross various barriers and confined surroundings, with concurrently occurring major changes of parasite cell architecture. Multicolour light sheet fluorescence microscopy provided information about tsetse tissue topology with unprecedented resolution and allowed the first 3D analysis of the infection process. High-speed fluorescence microscopy illuminated the versatile behaviour of trypanosome developmental stages, ranging from solitary motion and near-wall swimming to collective motility in synchronised swarms and in confinement. We correlate the microenvironments and trypanosome morphologies to high-speed motility data, which paves the way for cross-disciplinary microswimmer research in a naturally evolved environment.}, language = {en} } @article{HempelmannHartlebvanStraatenetal.2021, author = {Hempelmann, Alexander and Hartleb, Laura and van Straaten, Monique and Hashemi, Hamidreza and Zeelen, Johan P. and Bongers, Kevin and Papavasiliou, F. Nina and Engstler, Markus and Stebbins, C. Erec and Jones, Nicola G.}, title = {Nanobody-mediated macromolecular crowding induces membrane fission and remodeling in the African trypanosome}, series = {Cell Reports}, volume = {37}, journal = {Cell Reports}, number = {5}, doi = {10.1016/j.celrep.2021.109923}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-270285}, year = {2021}, abstract = {The dense variant surface glycoprotein (VSG) coat of African trypanosomes represents the primary host-pathogen interface. Antigenic variation prevents clearing of the pathogen by employing a large repertoire of antigenically distinct VSG genes, thus neutralizing the host's antibody response. To explore the epitope space of VSGs, we generate anti-VSG nanobodies and combine high-resolution structural analysis of VSG-nanobody complexes with binding assays on living cells, revealing that these camelid antibodies bind deeply inside the coat. One nanobody causes rapid loss of cellular motility, possibly due to blockage of VSG mobility on the coat, whose rapid endocytosis and exocytosis are mechanistically linked to Trypanosoma brucei propulsion and whose density is required for survival. Electron microscopy studies demonstrate that this loss of motility is accompanied by rapid formation and shedding of nanovesicles and nanotubes, suggesting that increased protein crowding on the dense membrane can be a driving force for membrane fission in living cells.}, language = {en} }