The companion of cellulose synthase 1 confers salt tolerance through a Tau-like mechanism in plants


C. Kesten; A. Wallmann; R. Schneider; H.E. McFarlane; A. Diehl; G.A. Khan; B.J. van Rossum; E.R. Lampugnani; W.G. Szymanski; N. Cremer; P. Schmieder; K.L. Ford; F. Seiter; J.L. Heazlewood; C. Sanchez-Rodriguez; H. Oschkinat*; S. Persson*

Nat. Commun. 10, 875 (2019)

Microtubules are filamentous structures necessary for cell division, motility and morphology, with dynamics critically regulated by microtubule-associated proteins (MAPs). Here we outline the molecular mechanism by which the MAP, COMPANION OF CELLULOSE SYNTHASE1 (CC1), controls microtubule bundling and dynamics to sustain plant growth under salt stress. CC1 contains an intrinsically disordered N-terminus that links microtubules at evenly distributed points through four conserved hydrophobic regions. By NMR and live cell analyses we reveal that two neighboring residues in the first hydrophobic binding motif are crucial for the microtubule interaction. The microtubule-binding mechanism of CC1 is reminiscent to that of the prominent neuropathology-related protein Tau, indicating evolutionary convergence of MAP functions across animal and plant cells.

Movie 1: CF488A‐labeled His‐CC1ΔC223 proteins (green) diffuse on surface bound microtubules (magenta) in vitro. Scale bar = 5 μm

Movie 2: Like GFP‐CC1, GFP‐CC1YYAA migrates as foci at the plasma membrane. Scale bar = 5 μm