Two examples of FRAP analysis of short epimastigote cells expressing TdT::IFT81. The distal portion of the flagellum was bleached with a brief laser pulse. Entry of new anterograde IFT trains in the flagellum can be monitored, they reach the distal tip where signal progressively comes backs before smaller, less bright, retrograde trains can be detected. The base and the tip of each flagellum are indicated. The square shows the portion of the flagellum that was photobleached. This video is related to Figure 6. The first cell goes briefly out of the plane of focus.