title: Active suppression of a leaf meristem orchestrates determinate leaf growth.
abstract: Leaves are flat determinate organs derived from indeterminate shoot apical meristems. The presence of a specific leaf meristem is debated, as anatomical features typical of meristems are not present in leaves. Here we demonstrate that multiple NGATHA (NGA) and CINCINNATA-class-TCP (CIN-TCP) transcription factors act redundantly, shortly after leaf initiation, to gradually restrict the activity of a leaf meristem inArabidopsis thalianato marginal and basal domains, and that their absence confers persistent marginal growth to leaves, cotyledons and floral organs. Following primordia initiation, the restriction of the broadly acting leaf meristem to the margins is mediated by the juxtaposition of adaxial and abaxial domains and maintained by WOX homeobox transcription factors, whereas other marginal elaboration genes are dispensable for its maintenance. This genetic framework parallels the morphogenetic program of shoot apical meristems and may represent a relic of an ancestral shoot system from which seed plant leaves evolved.
authors.affiliation: School of Biological Sciences, Monash University, Melbourne, Australia.
authors.forename: John Paul
authors.initials: JP
authors.lastname: Alvarez
authors.affiliation: School of Biological Sciences, Monash University, Melbourne, Australia.
authors.forename: Chihiro
authors.initials: C
authors.lastname: Furumizu
authors.affiliation: The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel.
authors.forename: Idan
authors.initials: I
authors.lastname: Efroni
authors.affiliation: Department of Plant and environmental Sciences, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Yuval
authors.initials: Y
authors.lastname: Eshed
authors.affiliation: School of Biological Sciences, Monash University, Melbourne, Australia.|Department of Plant Biology, University of California, Davis, Davis, California, United States.
authors.forename: John L
authors.identifier: 0000-0001-7347-3691
authors.initials: JL
authors.lastname: Bowman
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D005075:Biological Evolution; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D018519:Meristem / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D063245:Plant Development / Q000235:genetics*; D018515:Plant Leaves / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D059467:Transcriptome
chemical_list: D029681:Arabidopsis Proteins; D018398:Homeodomain Proteins; C543686:NGA1 protein, Arabidopsis thaliana; D020033:Protein Isoforms; C555805:TCP1 protein, Arabidopsis; D014157:Transcription Factors; C568610:WOX1 protein, Arabidopsis
keywords: A. thaliana; Arabidopsis; evolutionary biology; genomics; leaf development; leaf evolution; meristem; plant biology