Microtubule reassembly mediated by ethylene in response to salt stress (Plant Physiol.)

It has been shown previously that cortical microtubule reorganization contributes to adaptation to salt stress; however, the upstream factors that signal this response are not know. Ethylene has been shown to regulate microtubule stability and organization in roots and etiolated hypocotyls. Ethylene signaling can be blocked using Ag+ in presence of NaCl; Dou et al. observed cortical microtubule reassembly in pavement cells of plants expressing YFP-tubulin, after 36 and 48 hours of NaCl treatment. The seedlings treated with Ag+ and NaCl showed microtubule reassembly suppression. Further studies using only NaCl with the double mutant ein3eil1, showed a similar reduced microtubule reassembly. WDL5 is a microtubule stabilizing protein, which has been shown to be induced by EIN3. The knockout mutant of WDL5 wdl5-1 also showed a reduced microtubule reassembly after 30 hours. In the WDL5 overexpressor, cortical microtubules depolymerized less and recover faster than the WT; showing that WDL5 is a positive effector in ethylene mediated tolerance to salt stress. (Summary by Cecilia Vasquez) Plant Physiol. 10.1104/pp.17.01124