Planta

, Volume 214, Issue 1, pp 30–36 | Cite as

Early primordium morphogenesis during lateral root initiation in Arabidopsis thaliana

  • Joseph G. Dubrovsky
  • Thomas L. Rost
  • Adán Colón-Carmona
  • Peter Doerner
Original Article

Abstract.

The first morphogenetic events of lateral root primordium (LRP) formation in the Arabidopsis thaliana (L.) Heynh. pericycle occur soon after cells of the primary root complete elongation. Pericycle cells in direct contact with underlying protoxylem cells participate in LRP formation. Two types of LRP initiation were found, longitudinal uni- and bi-cellular. These occur when a single or two pericycle cells within a file, respectively, become founder cells for the entire longitudinal extent of the LRP. Histochemical and cytological analysis suggests that three is the minimum number of cells required to initiate an LRP. In young primordia comprising less than 32 cells, the average cell-doubling time was 3.7 h, indicating a drastic acceleration of cell cycle progression after lateral root initiation. Early in LRP development, cell growth is limited and therefore cytokinesis leads to a reduction of cell volume, similar to cleavage division cycles during animal and plant embryogenesis. The striking coordination of proliferation between pericycle cells in adjacent files in direct contact with the underlying protoxylem implies that inter-cellular signaling mechanisms act in the root apical meristem or later in development.

Arabidopsis (root initiation) Development Cell cycle Lateral root initiation Meristem Pericycle 

Copyright information

© Springer-Verlag 2001

Authors and Affiliations

  • Joseph G. Dubrovsky
    • 1
  • Thomas L. Rost
    • 2
  • Adán Colón-Carmona
    • 3
  • Peter Doerner
    • 3
  1. 1.Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz B.C.S., A. P. 128, México 23000
  2. 2.Section of Plant Biology, Division of Biological Sciences, University of California, Davis, CA 95616, USA
  3. 3.Plant Biology Laboratory, Salk Institute for Biological Studies, P.O. Box 85800, San Diego, CA 92186-5800, USA
  4. 4.Institute for Cell and Molecular Biology, University of Edinburgh, Edinburgh EH9 3JR, Scotland, UK
  5. 5.Present address: Department of Biology, University of Massachusetts, Boston, MA 02125-3393, USA
  6. 6.Present address: Departamento de Bioligía Molecular de Plantas, Instituto de Biotecnología, UNAM, A. P. 510-3, Cuernavaca Morelos 62271, México

Personalised recommendations