Abstract
Microtubule(MT) structure is highly conserved in eukaryotes. Stable heterodimers of α-tubulin and β-tubulin are stacked longitudinally to form a tubulin protofilament and 13 protofilaments are associated laterally to form a hollow MT. Previously, we showed that dominant negative left-handed helical growth mutants lefty1 and lefty2 have a missense mutation in two α-tubulins at the α-β interacting region of intradimer surface and form unstable MTs. In lefty1 and lefty2, cortical MTs(cMTs) of epidermal cells of root elongation zone show right-handed helical arrays. Therefore, we speculated correlation between twisting directions and cMT arrays.
Here, we screened Arabidopsis mutants that have mutations in tubulin genes and show helical growth phenotypes. Consequently, we obtained 24 mutants (14 right-handed mutants and 10 left-handed mutants). Quantitative analysis of MT arrangement demonstrated that all right-handed mutants have left-handed cMT arrays and left-handed mutants have right-handed cMT arrays.
Currentry, we are analyzing cMT dynamics of the mutants.
