The Microtubule-Associated Protein END BINDING1 Modulates Membrane Trafficking Pathways in Plant Root Cells

EB1 protein preferentially binds to the fast growing ends of microtubules where it regulates microtubule dynamics. In addition to microtubules, EB1 interacts with several additional proteins, and through these interactions modulates various cellular processes. Arabidopsis thaliana eb1 mutants have roots that exhibit aberrant responses to touch/gravity cues. Columella cells in the centre of the root cap are polarized and play key roles in these responses by functioning as sensors.I examined the cytoarchitecture of mutant columella cells to determine whether there were subcellular defects that might be correlated with aberrant responses to touch/gravity. No structural differences between mutant and wild type were found. However, by applying the lipophilic dye FM4-64 and actin disturbing drugs, I found that EB1 modulates membrane trafficking pathways possibly through an effect on the actin cytoskeleton. My results suggest that EB1 may affect root responses to touch/gravity signals by modulating membrane trafficking pathways in root cells.