An Auxin-Mediated Shift toward Growth Isotropy Promotes Organ Formation at the Shoot Meristem in Arabidopsis

Abstract : To control morphogenesis, molecular regulatory networks have to interfere with the mechanical properties of the indi-vidual cells of developing organs and tissues, but how this is achieved is not well known. We study this issue here in the shoot meristem of higher plants, a group of undifferenti-ated cells where complex changes in growth rates and direc-tions lead to the continuous formation of new organs [1, 2]. Here, we show that the plant hormone auxin plays an impor-tant role in this process via a dual, local effect on the extracellular matrix, the cell wall, which determines cell shape. Our study reveals that auxin not only causes a limited reduction in wall stiffness but also directly interferes with wall anisotropy via the regulation of cortical microtubule dy-namics. We further show that to induce growth isotropy and organ outgrowth, auxin somehow interferes with the cortical microtubule-ordering activity of a network of proteins, in-cluding AUXIN BINDING PROTEIN 1 and KATANIN 1. Numer-ical simulations further indicate that the induced isotropy is sufficient to amplify the effects of the relatively minor changes in wall stiffness to promote organogenesis and the establishment of new growth axes in a robust manner.
Type de document :
Article dans une revue
Current Biology - CB, Elsevier, 2014, 24 (19), pp.1 - 8. 〈10.1016/j.cub.2014.08.036〉
Liste complète des métadonnées

Littérature citée [33 références]  Voir  Masquer  Télécharger


https://hal.inria.fr/hal-01074821
Contributeur : Christophe Godin <>
Soumis le : mercredi 7 janvier 2015 - 10:57:46
Dernière modification le : vendredi 19 octobre 2018 - 15:22:02
Document(s) archivé(s) le : samedi 15 avril 2017 - 13:43:08

Fichiers

Sassi2014-2.pdf
Fichiers produits par l'(les) auteur(s)

Licence


Copyright (Tous droits réservés)

Identifiants

Citation

Massimiliano Sassi, Olivier Ali, Frédéric Boudon, Gladys Cloarec, Ursula Abad, et al.. An Auxin-Mediated Shift toward Growth Isotropy Promotes Organ Formation at the Shoot Meristem in Arabidopsis. Current Biology - CB, Elsevier, 2014, 24 (19), pp.1 - 8. 〈10.1016/j.cub.2014.08.036〉. 〈hal-01074821〉

Partager

Métriques

Consultations de la notice

992

Téléchargements de fichiers

469