{"id":2223,"date":"2017-03-09T21:23:36","date_gmt":"2017-03-09T20:23:36","guid":{"rendered":"http:\/\/ist.blogs.inra.fr\/afs\/?p=2223"},"modified":"2017-03-09T21:23:36","modified_gmt":"2017-03-09T20:23:36","slug":"modelling-wood-formation-and-structure-power-and-limits-of-a-morphogenetic-gradient-in-controlling-xylem-cell-proliferation-and-growth","status":"publish","type":"post","link":"https:\/\/ist.blogs.inrae.fr\/afs\/2017\/03\/09\/modelling-wood-formation-and-structure-power-and-limits-of-a-morphogenetic-gradient-in-controlling-xylem-cell-proliferation-and-growth\/","title":{"rendered":"Modelling wood formation and structure: power and limits of a morphogenetic gradient in controlling xylem cell proliferation and growth"},"content":{"rendered":"<script type='text\/javascript' src='https:\/\/d1bxh8uas1mnw7.cloudfront.net\/assets\/embed.js'><\/script><div id=\"ASec1\" class=\"AbstractSection\">\n<p class=\"Para\"><strong class=\"EmphasisTypeBold \">The emergence of the characteristic tree-ring pattern during xylogenesis is commonly thought to be controlled by a gradient of morphogen (auxin, TDIF peptide&#8230;). We show that this hypothesis accounts for several developmental aspects of wood formation, but not for the final anatomical structure.<\/strong><\/p>\n<\/div>\n<div id=\"ASec2\" class=\"AbstractSection\">\n<h3 class=\"Heading\"><strong class=\"EmphasisTypeBold \">Abstract<\/strong><\/h3>\n<p class=\"Para\">Wood formation is a dynamic cellular process displaying three generic features: (i) meristematic cell proliferation is restricted to the small cambial zone, preventing exponential xylem radial growth along the growing season; (ii) developmental processes result in a stable zonation of the developing xylem; (iii) the resulting mature wood cells form the typical tree-ring structure made of early and late wood with a gradient of cell sizes, an important trait for wood functioning in trees and for lumber quality. The mechanisms producing these spatial-temporal patterns remain largely unknown. According to the often-cited morphogenetic-gradient hypothesis, a graded concentration profile of a signalling molecule (e.g. auxin, TDIF) controls xylogenesis by providing positional information to differentiating cells. We assessed the predictions of the morphogenetic-gradient theory. We developed a computational model of wood formation implementing hypotheses on how a morphogen flows through the developing xylem and controls cell division and growth and we tested it against data produced by studies monitoring wood formation in conifers. We demonstrated that a morphogenetic gradient could indeed control xylem radial growth and wood-forming tissue zonation. However, it failed to explain the pattern of final cell sizes observed in tree-rings. We discussed the features that candidate additional regulatory mechanisms should meet.<\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<div id=\"ASec2\" class=\"AbstractSection\">\n<p class=\"Para\" style=\"text-align: justify\"><div class='altmetric-embed' data-badge-type='donut' data-doi='10.1007\/s13595-016-0613-y'  style='float: right; ' ><\/div><\/p>\n<\/div>\n<p style=\"text-align: justify\"><span style=\"color: #ff6600\"><a style=\"color: #ff6600\" href=\"http:\/\/link.springer.com\/article\/10.1007\/s13595-016-0613-y\"><strong>Read the full paper <\/strong><\/a><\/span><\/p>\n<hr \/>\n<p style=\"text-align: justify\"><span style=\"color: #808000\"><strong>Publication<\/strong><\/span><\/p>\n<p style=\"text-align: justify\">Hartmann FP, K. Rathgeber CB, Fournier M, Moulia B 2017. Modelling wood formation and structure: power and limits of a morphogenetic gradient in controlling xylem cell proliferation and growth. Ann. For. Sci. 74: 14. 10.1007\/s13595-016-0613-y.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The emergence of the characteristic tree-ring pattern during xylogenesis is commonly thought to be controlled by a gradient of morphogen (auxin, TDIF peptide&#8230;). We show that this hypothesis accounts for several developmental aspects of wood formation, but not for the final anatomical structure. Abstract Wood formation is a dynamic cellular process displaying three generic features: [&hellip;]<\/p>\n","protected":false},"author":35,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[15],"tags":[],"class_list":["post-2223","post","type-post","status-publish","format-standard","hentry","category-research-paper","cat-15-id"],"_links":{"self":[{"href":"https:\/\/ist.blogs.inrae.fr\/afs\/wp-json\/wp\/v2\/posts\/2223","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ist.blogs.inrae.fr\/afs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ist.blogs.inrae.fr\/afs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ist.blogs.inrae.fr\/afs\/wp-json\/wp\/v2\/users\/35"}],"replies":[{"embeddable":true,"href":"https:\/\/ist.blogs.inrae.fr\/afs\/wp-json\/wp\/v2\/comments?post=2223"}],"version-history":[{"count":0,"href":"https:\/\/ist.blogs.inrae.fr\/afs\/wp-json\/wp\/v2\/posts\/2223\/revisions"}],"wp:attachment":[{"href":"https:\/\/ist.blogs.inrae.fr\/afs\/wp-json\/wp\/v2\/media?parent=2223"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ist.blogs.inrae.fr\/afs\/wp-json\/wp\/v2\/categories?post=2223"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ist.blogs.inrae.fr\/afs\/wp-json\/wp\/v2\/tags?post=2223"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}