Discriminating motilities: Coordinating IFT with flagellar beating patterns

Abstract

Intraflagellar transport has traditionally been studied in immobilized flagella. In this issue, Gray et al. (https://doi.org/10.1083/jcb.202401154) introduced a novel methodology for fast imaging in free-swimming Leishmania, revealing the impacts of flagellum immobilization on intraflagellar transport and its inverse correlation with cell swimming speed.

Figure 1.

Illustration of flagellar beating patterns in Leishmania and their inverse correlation with IFT speed. Adhered parental cells showed slower IFT trains compared to genetically paralyzed cells. The advanced method developed by Gray and colleagues (6) enabled the observation of IFT in flagella free to move. Under these conditions, genetic modifications that altered beating patterns and swimming speeds inversely affected IFT speed: higher swimming speeds (High-frequency beat) resulted in slower IFT trains, while slower swimming speeds (Uncoordinated beat, Paralyzed flagella) led to faster IFT. The model suggests ATP competition between axonemal dyneins and IFT molecular motors.