Intraflagellar transport (IFT) is the rapid bidirectional movement of large protein complexes driven by kinesin and dynein motors along microtubule doublets of cilia and flagella. In this study, we used a combination of high-resolution electron and light microscopy to investigate how and where these IFT trains move within the flagellum of the protist Trypanosoma brucei. Focused ion beam scanning electron microscopy (FIB-SEM) analysis of trypanosomes showed that trains are found almost exclusively along two sets of doublets (3–4 and 7–8) and distribute in two categories according to their length. High-resolution live imaging of cells expressing mNeonGreen::IFT81 or GFP::IFT52 revealed for the first time IFT trafficking on two parallel lines within the flagellum. Anterograde and retrograde IFT occurs on each of these lines. At the distal end, a large individual anterograde IFT train is converted in several smaller retrograde trains in the space of 3–4 s while remaining on the same side of the axoneme.
Bertiaux, EloïseMallet, AdelineFort, CécileBlisnick, ThierryBonnefoy, SergeJung, JaminLemos, MoaraMarco, SergioVaughan, SueTrépout, SylvainTinevez, Jean-YvesBastin , Philippe
Faculty of Health and Life Sciences\Department of Biological and Medical Sciences
Year of publication: 2018Date of RADAR deposit: 2018-10-17