Synthetic tangled1 auxin-induced-in-roots9 mutant phenotype used to assess TANGLED1 function.

5 years ago

Synthetic tangled1 auxin-induced-in-roots9 mutant phenotype used to assess TANGLED1 function.

Henrik Buschmann, Carolyn Rasmussen, Ricardo Mir, Victoria H Morris

TANGLED1 (TAN1) and AUXIN-INDUCED-IN-ROOTS 9 (AIR9) are microtubule binding proteins with cortical division site localization in plants. Their function in Arabidopsis thaliana remained unclear because neither tan1 nor air9 single mutants have a strong phenotype. We show that tan1 air9 double mutants have a synergistic phenotype consisting of short, twisted roots that are hypersenstive to a microtubule depolymerizing drug. The tan1 air9 double mutants have significant defects in division plane orientation due to failures in placing the new cell wall at the correct division site. Full-length TAN1 fused to yellow-fluorescent-protein TAN1-YFP and several deletion constructs were transformed into the double mutant to assess which regions of TAN1 are required for its function in root growth, root twisting, and division plane orientation. TAN1-YFP expressed in the tan1 air9 significantly rescued the double mutant phenotype in root growth, root twisting, and division plane orientation. Interestingly, TAN1 missing the first 126 amino acids, TAN1-∆I-YFP, failed to rescue the double mutant phenotype, while TAN1 missing a conserved middle region, TAN1-∆II-YFP, significantly rescued the mutant phenotype in terms of root growth and division plane orientation but not root twisting. Root twisting of TAN1-∆II-YFP tan1 air9 plants separated mitotic from putative interphase function. The tan1 air9 double mutant is a powerful tool for understanding TAN1 function in A. thaliana.

Publisher URL: http://doi.org/10.1104/pp.17.01075

DOI: 10.1104/pp.17.01075