Panel A shows immunostaining images of endogenous K I F 3 components at the proximal axon, highlighting co-localizing puncta and independent puncta. Panel B presents quantification of the minimum distance between K I F 3 components, displayed as bar graphs with mean and standard deviation, and dot plots. The data is expressed in the X is greater than Y format, representing the distance from protein X to protein Y. Panel C shows representative images of E G F P-K I F 3 A and myc-KIF3B in individual cells under rigorous conditions, with alpha-tubulin co-stained to confirm neurite orientation. Panel D provides enlarged views of both axonal and somatodendritic regions, showing co-localizing puncta of K I F 3 A and K I F 3 B as well as single puncta. Panel E presents statistical analysis of K I F 3 A and K I F 3 B overlap in the rigor state, with data shown as a bar graph with mean and standard deviation, and dot plots. Pearson's correlation coefficients indicate greater overlap between K I F 3 A and K I F 3 B in the somatodendritic region compared to the axonal region. All data is approximate.
KIF3 exhibits diversity in its components at the AIS. (A) Immunostaining images of endogenous KIF3 components at proximal axon. All combination has co-localizing puncta (arrowheads) and independent puncta (arrows). Scale bar, 2 µm. (B) Quantification of the minimum distance between KIF3 components. Data are presented as bar graphs with mean ± SD and dot plots. Protein distance is expressed in the X > Y format, representing the distance from protein X to protein Y. A: KIF3A, B: KIF3B, P: KAP3. Due to the large number of pairwise comparisons, details of the significance tests are provided in Fig. S1 M. Representative significant differences are indicated as ***(P < 0.001). n = 170 for each combination, obtained by randomly sampling 10 puncta from each of 17 neurons. (C) Representative images showing EGFP-KIF3A (EGFP signal) and myc-KIF3B (anti-myc immunoreactivity) in individual cells under rigor conditions. To confirm neurite orientation and detect ROIs, α-tubulin was co-stained. Dashed boxes (left: somatodendritic; right: axonal) are enlarged in D. Arrowheads indicate soma, and arrows indicate axons (longest neurites). Scale bar, 10 µm. (D) Enlarged views. In both axonal and somatodendritic regions, co-localizing puncta of KIF3A and KIF3B (arrowheads) as well as single puncta (arrows) were observed. Notably, axonal regions showed more KIF3B-only puncta. Scale bar, 2 µm. (E) Statistical analysis of KIF3A and KIF3B overlap in rigor state. Data are shown as bar graphs with mean ± SD and dot plots, with data from the same cells connected by gray lines. Pearson’s correlation coefficients were significantly higher in the somatodendritic region, indicating greater overlap between KIF3A and KIF3B. In contrast, overlap between KIF3A and KIF3B was reduced in the axonal region. P = 0.0001 by Welch’s t test. n = 11 neurons.