Open AccessInsights into cortical microtubule nucleation and dynamics in Arabidopsis leaf cells
Author(s) -
Noriyoshi Yagi,
Sachihiro Matsunaga,
Takashi Hashimoto
Publication year - 2017
Publication title -
journal of cell science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.384
H-Index - 278
eISSN - 1477-9137
pISSN - 0021-9533
DOI - 10.1242/jcs.203778
Subject(s) - biology , arabidopsis , microtubule , microtubule nucleation , nucleation , microbiology and biotechnology , dynamics (music) , botany , neuroscience , evolutionary biology , cell , centrosome , genetics , mutant , gene , cell cycle , chemistry , physics , organic chemistry , acoustics
Plant microtubules (MTs) are nucleated from the γ-tubulin-containing ring complex (γTuRC). In cortical MT arrays of interphase plant cells, γTuRC is preferentially recruited to the lattice of preexisting MTs, where it initiates MT nucleation in either a branch- or bundle-forming manner, or dissociates without nucleation. In this study, we analyzed how γTuRCs influence MT nucleation and dynamics in cotyledon pavement cells of Arabidopsis thaliana. We found that γTuRC nucleated MTs at angles of approximately 40 degrees toward the plus-ends of existing MTs, or in predominantly antiparallel bundles. A small fraction of γTuRCs was motile and tracked MT ends. When γTuRCs decorated the depolymerizing MT end, they reduced the depolymerization rate. Non-nucleating γTuRCs associated with the MT lattice promoted rescue events. These results suggest that γTuRCs not only nucleate MT growth but also regulate MT dynamics by stabilizing MT ends. On rare occasions, a non-MT-associated γTuRC was pushed in the direction of the MT minus-end, while nucleating a new MT, suggesting that the polymerizing plus-end is anchored to the plasma membrane.