Objective We propose a combined biological, geometrical and physical study of shape formation during the development of leaves. We will test our hypothesis that the formation of complex structures during leaf patterning involves theinterplay between genetic properti es of the plant and mechanical instabilities. We show, based on geometrical principles, that simple growth profiles can generate mechanical stresses within the tissue and induce mechanical instabilities, such as buckling, wrinkling and strain focusing. The se instabilities break the spatial symmetry by setting length scales and by "marking sites" on the leaf, where stresses are concentrated. Stress concentration, then, could affect further patterning of the tissue through differential growth and differentiat ion, leading to the observed complex structures. According to the new view we propose, genes involved in patterning are not, necessarily, responsible for a direct "shaping" of the leaf. Instead, they may control leaf shape and veins formation by generating simple "growth laws" and by controlling the tissue sensitivity to mechanical stresses, partially through the control of biosynthesis and activity of plant hormones. The proposed principles can be extended to include a wider class of developing systems. T he proposed work is intrinsically interdisciplinary. It will combine novel ideas and experimental techniques from both biological and physical disciplines and will integrate the specialties of several laboratories, located at different EU member/associated states. We expect the research to impact the way the development of organisms, and plants in particular, is understood. The tools developed in the proposed research will potentially be applicable to other scientific and technological fields, such as the d evelopment of industrial, highly deformable materials and the study of cancer tumors. The research is not compatible with any FP6 thematic priority, but fits well within ADVENTURE's spirit. Fields of science medical and health sciencesclinical medicineoncologysocial scienceslaw Keywords Gaussian curvature buckling differential growth fracture knox genes leaf patterning leaf venation meristem metric nonlinear physics symmetry breaking thin sheets elasticity wrinkling Programme(s) FP6-POLICIES - Policy support: Specific activities covering wider field of research under the Focusing and Integrating Community Research programme 2002-2006. Topic(s) NEST-2003-1 - Adventure activities Call for proposal FP6-2003-NEST-B-1 See other projects for this call Funding Scheme STREP - Specific Targeted Research Project Coordinator THE HEBREW UNIVERSITY OF JERUSALEM Address The hebrew university, mt scopus Jerusalem Israel See on map Links Website Opens in new window EU contribution € 0,00 Participants (4) Sort alphabetically Sort by EU Contribution Expand all Collapse all CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE (CNRS) France EU contribution € 0,00 Address 3, rue michel-ange Paris See on map Links Website Opens in new window THE CHANCELLOR, MASTERS AND SCHOLARS OF THE UNIVERSITY OF OXFORD United Kingdom EU contribution € 0,00 Address University offices, wellington square Oxford See on map Links Website Opens in new window UNIVERSITAET BERN Switzerland EU contribution € 0,00 Address Hochschulstrasse 4 Bern See on map Links Website Opens in new window UNIVERSITE PARIS 7 DENIS DIDEROT France EU contribution € 0,00 Address Place jussieu 2 Paris See on map Links Website Opens in new window
