Figure 4.

Microtubule organization and dynamics in the adaxial cotyledon epidermis of 5 days after germination (DAG) actin nucleator mutants expressing GFP-MAP4. (A) Representative images of microtubule organization in wt, fh1-1, arpc5-1, and fh1-1 arpc5-1 seedlings. (B) Quantitative estimate of microtubule bundling, measured as skewness of fluorescence intensity distribution among labeled structures. (C) Quantitative estimate of microtubule network density, measured as pixel occupancy of skeletonized meshwork. (D) Microtubule or bundle lifetime, represented by maximum values observed over 120 s in structures crossing a 2 µm transect. (E) Microtubule or bundle lateral mobility, represented by maximum trajectories observed over 120 s in structures crossing a 2 µm transect. Statistical significance of differences is denoted by asterisks (* for p < 0.05, ** for p < 0.01).