Cortical microtubule patterning in roots of Arabidopsis thaliana primary cell wall mutants reveals the bidirectional interplay with cell expansion

The MATH-BTB Protein TaMAB2 Accumulates in Ubiquitin-Containing Foci and Interacts With the Translation Initiation Machinery in Arabidopsis

“…Different types of MT arrays were detected in marker line including cortical MTs, preprophase band, mitotic spindle, and phragmoplast MTs. MTs of different lengths were oriented in various angles relative to the root axis from longitudinal to transversal ( Figure 3E , upper) as previously described (Sugimoto et al, 2000; Panteris et al, 2015). By contrast, MTs of TaMAB2- overexpressing plants of both crossbreeds displayed extensive bundling and oblique positioning relative to the root axis ( Figure 3E , lower, represented by EM4) indicating a role of TaMAB2 in mediating microtubule bundling and orientation during cell elongation.…”

Update: Plant Cortical Microtubule Arrays

“…Treatment with inhibitors of cellulose synthesis, including isoxaben or 2,6-dichlorobenzonitrile, led to a wider range of microtubule orientations in root tip cells (Himmelspach et al, 2003;Peng et al, 2013) and a reorientation of cortical microtubule arrays from a transverse to a longitudinal coalignment in cells at the root elongation zone (Paredez et al, 2008;Panteris et al, 2013). Disruption of normal microtubule organization also was observed in cases where mutations affected cellulose biosynthesis genes, including CESA1, CESA3, CESA6, CSI1, and KORRIGAN (Paredez et al, 2008;Panteris et al, 2013Panteris et al, , 2014. The notion of cell wall feedback is further supported by chemical and genetic perturbation of other cell wall components, including xyloglucans and arabinogalactans, that led to disorganization and reduced stability of cortical microtubules (Nguema-Ona et al, 2007;Driouich and Baskin, 2008;Xiao et al, 2016).…”

“CLASPing” tungsten's effects on microtubules with “PINs”

“…It has been stated that reduced root growth of A. thaliana is probably due to defective cell expansion in the elongation zone, resulting in the dwarfish appearance of tungsten-treated plants. 7 As cell expansion and cortical microtubule orientation are interconnected, 10,11 tungsten's effects on cortical microtubule orientation in A. thaliana roots were investigated in further detail. In untreated roots, cortical microtubules followed distinct orientation patterns, as already described.…”

“…18 Arrest of elongation in transition zone cells may result in microtubule reorientation, as generally occurs by cessation of expansion. 10,11 As a second step, tungsten affects CLASP expression ( Fig. 3B and C).…”