Cell division activity during apical hook development

Plant Physiol. 2001 Jan;125(1):219-26. doi: 10.1104/pp.125.1.219.

Abstract

Growth during plant development is predominantly governed by the combined activities of cell division and cell elongation. The relative contribution of both activities controls the growth of a tissue. A fast change in growth is exhibited at the apical hypocotyl of etiolated seedlings where cells grow at different rates to form a hook-like structure, which is traditionally assumed to result from differential cell elongation. Using new tools we show asymmetric distribution of cell division during early stages of hook development. Cell divisions in the apical hook were predominantly found in subepidermal layers during an early step of hook development, but were absent in mutants exhibiting a hookless phenotype. In addition, during exaggeration of hook curvature, which is mediated by ethylene, a rapid change in the combined activities of cell division and cell elongation was detected. Our results indicate a fast change in cell division activity during apical hook development. We suggest that cell division together with cell elongation contributes to apical hook growth. Our results emphasize the change in the relative contribution of cell division and cell elongation in a fast growing structure like the apical hook.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aphidicolin / pharmacology
  • Cell Division / physiology*
  • Cyclin B / genetics
  • Cyclin B / physiology
  • Darkness
  • Ethylenes / metabolism
  • Glucuronidase / genetics
  • Glucuronidase / metabolism
  • Hydroxyurea / pharmacology
  • Hypocotyl / cytology
  • Hypocotyl / drug effects
  • Light
  • Mitosis
  • Plants, Genetically Modified / cytology*
  • Plants, Genetically Modified / drug effects
  • Plants, Genetically Modified / growth & development
  • Recombinant Fusion Proteins / metabolism
  • Seeds / cytology
  • Seeds / drug effects
  • Seeds / physiology

Substances

  • Cyclin B
  • Ethylenes
  • Recombinant Fusion Proteins
  • Aphidicolin
  • ethylene
  • Glucuronidase
  • Hydroxyurea