Fig. 5: Kinesin is involved in the directional movement of VN.

a, b Time-lapse images of H2B-GFP in DMSO- (a) or BTB-1-treated growing pollen tubes (b). Images were enlarged to show VN morphology. Bar, 30 μm. c, d Kymograph analysis of (a) and (b). e Quantification of VN’s movement velocity in DMSO and BTB-1 treatment. Velocity of VN forward movement, DMSO (n = 310), BTB-1 (n = 342); velocity of VN backward movement, DMSO (n = 63), BTB-1 (n = 78), n from 10 cells for each treatment. f The frequency distribution of the distance of VN to the tip of DMSO and BTB-1 treatment. g, h Time-lapse images of H2B-GFP in WT (g) or kin14g kin14h double mutant growing pollen tubes (h). Bar, 30 μm. i, j Kymograph analysis of (g) and (h). k Quantification of VN’s movement velocity in WT and kinesin mutants. Velocity of VN forward movement, WT (n = 402), kin14g (n = 393), kin14h (n = 416) from 10 cells for each genotype, kin14g kin14h (n = 521) from 14 cells. Velocity of VN backward movement, WT (n = 66), kin14g (n = 49), kin14h (n = 45) from 10 cells for each genotype, kin14g kin14h (n = 66) from 14 cells. l The distance of the VN to the tip of WT and kinesin mutants. WT (n = 795), kin14g (n = 645), kin14h (n = 778), kin14g kin14h (n = 745) from 10 cells for each genotype. m Time-lapse images of mCherry-MBD and H2B-GFP in pollen tubes after oryzalin and BTB-1 co-treatment and followed by oryzalin washout. The region marked with white dotted squares is enlarged in the right panels. Arrow indicates the reassembly site of microtubules. Arrowheads indicate the contact sites of VN tips and microtubules. Bar in the left panel, 10 μm; bar in the right panel, 5 μm. n Kymograph analysis of (m). Values are mean ± SD; *P < 0.05, **P < 0.01, ***P < 0.001, ns, not significant; two-tailed Student’s t-test in (e), (k), (l). Source data are provided as a Source Data file.