Figure 6.

ark1-1 Microtubule Phenotype Is Restricted to Root Hair-Forming Cells.

(A) Microtubule plus-end growth velocities are not significantly different in the pavement cells of wild-type (3.7 ± 0.6 μm/min, n = 409) and ark1-1 (3.7 ± 0.6 μm/min, n = 153) cotyledons. Four wild-type and ark1-1 plants each were imaged.

(B) Microtubule catastrophe frequencies in ark1-1 (0.020 ± 0.013 events/second) and wild-type cotyledon pavement cells (0.020 ± 0.011 events/second) are not significantly different. Catastrophe frequencies of microtubules were measured in the same cells as in (A).

(C) Microtubule growth and shrinkage velocities in wild-type (growth, 5.0 ± 2.8 μm/min, n = 371; shrinkage, 15.3 ± 9.2 μm/min, n = 37) and ark1-1 (growth, 5.3 ± 2.8 μm/min, n = 286; shrinkage, 13.6 ± 6.3 μm/min, n = 34) elongating hypocotyls are not significantly different from each other. Two (wild-type) and seven (ark1-1) plants were imaged.

Data and bars are represented as mean ± sd, respectively.