IFT proteins are found on two distinct lines along the axoneme in fixed cells. (A and B) Control trypanosomes (strain expressing YFP::ODA8; Bonnefoy et al., 2018) were fixed in paraformaldehyde followed by methanol after fixation and processed for immunofluorescence using a marker antibody for the axoneme (middle; magenta on the merged image) and a monoclonal antibody against IFT172 (right; green on the merged image). The leftmost panel shows the phase-contrast image merged with DAPI staining (cyan). (A) Cell with one flagellum. (B) Cell assembling a new flagellum. In both cases, a single continuous thick line was observed for the axoneme marker, whereas discontinuous staining spreading on two close but distinct lines was visible for IFT172.