SFPQ-containing transport granules move in a bidirectional manner in axons of DRG sensory neurons. (A) Time lapse images of Halo-SFPQ in stationary (star), anterograde (closed arrowhead), and retrograde phase (open arrowhead). Scale bar: 1.2 µm. (B) Shape aspect ratio (maximum diameter/minimum diameter) of SFPQ granules calculated for stationary and moving granules, categorized with their instantaneous velocities as indicated. Data are calculated from 24 SFPQ granules from five axons from five independent microfluidic experiments for time points in stationary (n = 28), ≤0.5 (n = 33), 0.5–1 (n = 28), 1–2 (n = 28), 2–3 (n = 25), and >3 µm/s (n = 11). ****P < 0.0001; ***P = 0.0003; **P = 0.0018; *P = 0.0354, 0.0308 with one-way ANOVA. (C) Kymograph depicting Halo-SFPQ in stationary (star), anterograde (closed arrowhead), and retrograde (open arrowhead) phase. Scale bars: 2 µm and 9 s. (D) Fraction of SFPQ granules spent in stationary, anterograde, or retrograde phase. (E and F) Average velocity (E) and average run length (F) of Halo-tagged SFPQ granules in axons for anterograde and retrograde transport. **P = 0.0032 by unpaired two-paired t test; data represent mean ± SEM. Data from D, E, and F are analyzed from 259 SFPQ particles from 34 axons across four independent microfluidic experiments.