title: The CLE40 and CRN/CLV2 signaling pathways antagonistically control root meristem growth in Arabidopsis.
abstract: Differentiation processes in the primary root meristem are controlled by several signaling pathways that are regulated by phytohormones or by secreted peptides. Long-term maintenance of an active root meristem requires that the generation of new stem cells and the loss of these from the meristem due to differentiation are precisely coordinated. Via phenotypic and large-scale transcriptome analyses of mutants, we show that the signaling peptide CLE40 and the receptor proteins CLV2 and CRN act in two genetically separable pathways that antagonistically regulate cell differentiation in the proximal root meristem. CLE40 inhibits cell differentiation throughout the primary root meristem by controlling genes with roles in abscisic acid, auxin, and cytokinin signaling. CRN and CLV2 jointly control target genes that promote cell differentiation specifically in the transition zone of the proximal root meristem. While CRN and CLV2 are not acting in the CLE40 signaling pathway under normal growth conditions, both proteins are required when the levels of CLE40 or related CLE peptides increase. We show here that two antagonistically acting pathways controlling root meristem differentiation can be activated by the same peptide in a dosage-dependent manner.
authors.affiliation: Institute for Developmental Genetics and Cluster of Excellence on Plant Sciences (CEPLAS), Universitätsstr. 1, Heinrich-Heine University, 40225 Düsseldorf, Germany.
authors.forename: Helge
authors.initials: H
authors.lastname: Pallakies
authors.affiliation: Institute for Developmental Genetics and Cluster of Excellence on Plant Sciences (CEPLAS), Universitätsstr. 1, Heinrich-Heine University, 40225 Düsseldorf, Germany. Electronic address: ruediger.simon@hhu.de.
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Simon
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002454:Cell Differentiation; D003583:Cytokinins / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D018519:Meristem / Q000254:growth & development*; D018517:Plant Roots / Q000254:growth & development*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism; D017423:Sequence Analysis, RNA; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; C506683:CLE40 protein, Arabidopsis; C401621:CLV2 protein, Arabidopsis; D003583:Cytokinins; D007210:Indoleacetic Acids; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; D000040:Abscisic Acid; C548152:CORYNE protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases
keywords: CLE40; CRN/CLV2; phytohormones.; root meristem; signaling peptides; transcriptomics