--- _id: '1852' abstract: - lang: eng text: To control morphogenesis, molecular regulatory networks have to interfere with the mechanical properties of the individual 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 undifferentiated cells where complex changes in growth rates and directions lead to the continuous formation of new organs [1, 2]. Here, we show that the plant hormone auxin plays an important 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 dynamics. 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, including AUXIN BINDING PROTEIN 1 and KATANIN 1. Numerical 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. acknowledgement: 'This work was funded by grants from EraSysBio+ (iSAM) and ERC (Morphodynamics). ' author: - first_name: Massimiliano full_name: Sassi, Massimiliano last_name: Sassi - first_name: Olivier full_name: Ali, Olivier last_name: Ali - first_name: Frédéric full_name: Boudon, Frédéric last_name: Boudon - first_name: Gladys full_name: Cloarec, Gladys last_name: Cloarec - first_name: Ursula full_name: Abad, Ursula last_name: Abad - first_name: Coralie full_name: Cellier, Coralie last_name: Cellier - first_name: Xu full_name: Chen, Xu id: 4E5ADCAA-F248-11E8-B48F-1D18A9856A87 last_name: Chen - first_name: Benjamin full_name: Gilles, Benjamin last_name: Gilles - first_name: Pascale full_name: Milani, Pascale last_name: Milani - first_name: Jirí full_name: Friml, Jirí id: 4159519E-F248-11E8-B48F-1D18A9856A87 last_name: Friml orcid: 0000-0002-8302-7596 - first_name: Teva full_name: Vernoux, Teva last_name: Vernoux - first_name: Christophe full_name: Godin, Christophe last_name: Godin - first_name: Olivier full_name: Hamant, Olivier last_name: Hamant - first_name: Jan full_name: Traas, Jan last_name: Traas citation: ama: Sassi M, Ali O, Boudon F, et al. An auxin-mediated shift toward growth isotropy promotes organ formation at the shoot meristem in Arabidopsis. Current Biology. 2014;24(19):2335-2342. doi:10.1016/j.cub.2014.08.036 apa: Sassi, M., Ali, O., Boudon, F., Cloarec, G., Abad, U., Cellier, C., … Traas, J. (2014). An auxin-mediated shift toward growth isotropy promotes organ formation at the shoot meristem in Arabidopsis. Current Biology. Cell Press. https://doi.org/10.1016/j.cub.2014.08.036 chicago: Sassi, Massimiliano, Olivier Ali, Frédéric Boudon, Gladys Cloarec, Ursula Abad, Coralie Cellier, Xu Chen, et al. “An Auxin-Mediated Shift toward Growth Isotropy Promotes Organ Formation at the Shoot Meristem in Arabidopsis.” Current Biology. Cell Press, 2014. https://doi.org/10.1016/j.cub.2014.08.036. ieee: M. Sassi et al., “An auxin-mediated shift toward growth isotropy promotes organ formation at the shoot meristem in Arabidopsis,” Current Biology, vol. 24, no. 19. Cell Press, pp. 2335–2342, 2014. ista: Sassi M, Ali O, Boudon F, Cloarec G, Abad U, Cellier C, Chen X, Gilles B, Milani P, Friml J, Vernoux T, Godin C, Hamant O, Traas J. 2014. An auxin-mediated shift toward growth isotropy promotes organ formation at the shoot meristem in Arabidopsis. Current Biology. 24(19), 2335–2342. mla: Sassi, Massimiliano, et al. “An Auxin-Mediated Shift toward Growth Isotropy Promotes Organ Formation at the Shoot Meristem in Arabidopsis.” Current Biology, vol. 24, no. 19, Cell Press, 2014, pp. 2335–42, doi:10.1016/j.cub.2014.08.036. short: M. Sassi, O. Ali, F. Boudon, G. Cloarec, U. Abad, C. Cellier, X. Chen, B. Gilles, P. Milani, J. Friml, T. Vernoux, C. Godin, O. Hamant, J. Traas, Current Biology 24 (2014) 2335–2342. date_created: 2018-12-11T11:54:22Z date_published: 2014-10-06T00:00:00Z date_updated: 2021-01-12T06:53:37Z day: '06' department: - _id: JiFr doi: 10.1016/j.cub.2014.08.036 intvolume: ' 24' issue: '19' language: - iso: eng main_file_link: - open_access: '1' url: https://hal.archives-ouvertes.fr/hal-01074821 month: '10' oa: 1 oa_version: Submitted Version page: 2335 - 2342 publication: Current Biology publication_status: published publisher: Cell Press publist_id: '5248' quality_controlled: '1' scopus_import: 1 status: public title: An auxin-mediated shift toward growth isotropy promotes organ formation at the shoot meristem in Arabidopsis type: journal_article user_id: 4435EBFC-F248-11E8-B48F-1D18A9856A87 volume: 24 year: '2014' ...