Proprioception as a key control of gravitropic mouvements and plant posture in the aerial organs of plants - Université Paris Cité Accéder directement au contenu
Poster De Conférence Année : 2015

Proprioception as a key control of gravitropic mouvements and plant posture in the aerial organs of plants

Résumé

Gravitropism, the turning movement of plants aligning to the direction of gravity is a salient trait of land plants. If its motors and early signaling have been thoroughly investigated, the control of the overall movement and its capacity to effectively align to the gravity direction has only started to be elucidated recently. This has been achieved by combining i) quantitative records of the kinematics of tropism in 11 plant species sampling angiosperms phylogeny and ii) a heuristic modelling of the dynamics and diversity of the bending and straightening process. It was shown that the sensing of the local inclination angle by statocytes is not sufficient to bring the organ back to the gravity direction after tilting. Alignment to the direction of gravity and proper control of the plant posture can only be achieved through a balanced cross-talk between gravisensing and a proprioceptive control, tending to straighten the organ. This balance is captured by a single dimensionless number B that fully controls the diversity of the movement and of the final posture of the plant. Moreover, our results suggest that the proprioceptive sensitivity has been selectively tuned to avoid the two pitfalls of tropism through differential growth: curvature fixing where growth stops and passive orientation drift. A parsimonious universal model of the graviproprioceptive control of plant gravitropism, the AC model, has been developed, and found valid over the all species sample and two orders of magnitude of organ size. Further investigation has revealed that the proprioception of bending deformations during the tropic movement is consistent with the Sum of Strain-Sensing model (S3m) developed for strain-mechanosensing during bending by external loads. Finally a model-assisted, noncontact phenotyping of the gravi-proprioceptive balance B has been developed and used to screen mutants for graviproprioceptive control so to investigate the molecular genetics of its mechanobiological regulation.
Fichier non déposé

Dates et versions

hal-01269107 , version 1 (05-02-2016)

Identifiants

  • HAL Id : hal-01269107 , version 1
  • PRODINRA : 310456

Citer

Bruno Moulia, Catherine Coutand, Nathalie Leblanc-Fournier, S. Douady, Renaud Bastien. Proprioception as a key control of gravitropic mouvements and plant posture in the aerial organs of plants. 3. International Symposium on Plant, Signaling & Behavior, Jun 2015, Paris, France. Univ. Paris Diderot Publischers, pp.134, 2015, 3. International Symposium on Plant Signaling & Behavior. ⟨hal-01269107⟩
177 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More