Microtubule dynamics and organization in the plant cortical array.
Live-cell studies have brought fresh insight into the organizational activities of the plant cortical array. Plant interphase arrays organize in the absence of a discrete microtubule organizing center, having plus and minus ends distributed throughout the cell cortex. Microtubule nucleation occurs at the cell cortex, frequently followed by minus-end detachment from origin sites. Microtubules associate tightly with the cell cortex, resisting lateral and axial translocation. Slow, intermitant loss of dimers from minus ends, coupled with growth-biased dynamic instability at the plus ends, results in the migration of cortically attached microtubules across the cell via polymer treadmilling. Microtubule-microtubule interactions, a direct consequence of treadmilling, result in polymer reorientation and creation of polymer bundles. The combined properties of microtubule dynamics and interactions among polymers constitute a system with predicted properties of self-organization.
Ehrhardt
David W
DW
Department of Plant Biology, Carnegie Institution, Stanford, California 94020, USA. ehrhardt@stanford.edu
Shaw
Sidney L
SL