Format

Send to

Choose Destination
J Cell Sci. 2018 Jan 29;131(2). pii: jcs203778. doi: 10.1242/jcs.203778.

Insights into cortical microtubule nucleation and dynamics in Arabidopsis leaf cells.

Author information

1
Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
2
Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan.
3
Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan hasimoto@bs.naist.jp.

Abstract

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 mediating 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 ∼40° 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 MT regrowth after a depolymerization phase. 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.

KEYWORDS:

Arabidopsis thaliana; Dynamics; Microtubule; Nucleation

PMID:
28615412
DOI:
10.1242/jcs.203778
Free full text

Conflict of interest statement

Competing interestsThe authors declare no competing or financial interests.

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center