Forskning ved Københavns Universitet - Københavns Universitet


Mechanical induction of lateral root initiation in Arabidopsis thaliana

Publikation: Bidrag til tidsskriftTidsskriftartikelForskning

  • Franck Anicet Ditengou
  • William D Teale
  • Philip Kochersperger
  • Karl Andreas Flittner
  • Irina Kneuper
  • Eric van der Graaff
  • Hugues Nziengui
  • Francesco Pinosa
  • Xugang Li
  • Roland Nitschke
  • Thomas Laux
  • Klaus Palme
Lateral roots are initiated postembryonically in response to environmental cues, enabling plants to explore efficiently their underground environment. However, the mechanisms by which the environment determines the position of lateral root formation are unknown. In this study, we demonstrate that in Arabidopsis thaliana lateral root initiation can be induced mechanically by either gravitropic curvature or by the transient bending of a root by hand. The plant hormone auxin accumulates at the site of lateral root induction before a primordium starts to form. Here we describe a subcellular relocalization of PIN1, an auxin transport protein, in a single protoxylem cell in response to gravitropic curvature. This relocalization precedes auxin-dependent gene transcription at the site of a new primordium. Auxin-dependent nuclear signaling is necessary for lateral root formation; arf7/19 double knock-out mutants normally form no lateral roots but do so upon bending when the root tip is removed. Signaling through arf7/19 can therefore be bypassed by root bending. These data support a model in which a root-tip-derived signal acts on downstream signaling molecules that specify lateral root identity.
TidsskriftProceedings of the National Academy of Sciences of the United States of America
Udgave nummer48
Sider (fra-til)18818-23
Antal sider6
StatusUdgivet - 2 dec. 2008
Eksternt udgivetJa

ID: 106391267