Microtubule dynamics in root hairs of Medicago truncatula.
The microtubular cytoskeleton plays an important role in the development of tip-growing plant cells, but knowledge about its dynamics is incomplete. In this study, root hairs of the legume Medicago truncatula have been chosen for a detailed analysis of microtubular cytoskeleton dynamics using GFP-MBD and EB1-YFP as markers and 4D imaging. The microtubular cytoskeleton appears mainly to be composed of bundles which form tracks along which new microtubules polymerise. Polymerisation rates of microtubules are highest in the tip of growing root hairs. Treatment of root hairs with Nod factor and latrunculin B result in a twofold decrease in polymerisation rate. Nonetheless, no direct, physical interaction between the actin filament cytoskeleton and microtubules could be observed. A new picture of how the plant cytoskeleton is organised in apically growing root hairs emerges from these observations, revealing similarities with the organisation in other, non-plant, tip-growing cells.
Timmers
Antonius C J
AC
Laboratory of Plant-Microorganism Interactions, CNRS INRA, UMR2594, 24 Chemin de Borde Rouge, BP 52627, F-31326 Castanet-Tolosan, France. timmers@toulouse.inra.fr
Vallotton
Pascal
P
Heym
Claudia
C
Menzel
Diedrik
D
D000199:Actins / Q000502:physiology; D003599:Cytoskeleton / Q000187:drug effects / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000494:pharmacology; D046913:Medicago truncatula / Q000502:physiology*; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000187:drug effects / Q000502:physiology*; D018517:Plant Roots / Q000254:growth & development*; D012231:Rhizobium / Q000502:physiology; D050257:Tubulin Modulators / Q000494:pharmacology
D000199:Actins; D008070:Lipopolysaccharides; C092082:Nod factor IV, Rhizobium meliloti; D050257:Tubulin Modulators; D049452:Green Fluorescent Proteins