title: Root development: signaling down and around.
abstract: Because of its elegant simplicity, the Arabidopsis root has become a model for studying plant organogenesis. In this review we focus on recent results indicating the importance of signaling in root development. A role for positional information in root cell specification has been demonstrated by ablation analyses. Through mutational analysis, genes have been identified that play a role in radial pattern formation. The embryonic phenotypes of these mutants raised the possibility that division patterns in post-embryonic roots are dependent on signaling that originates during embryonic development. Analysis of expression of the SCARECROW gene indicates that it may play a role in this 'top-down' signaling process. Characterization of root epidermis development has led to the identification of negative regulators of root-hair formation. These appear to set up a prepattern which is reinforced by signaling by plant hormones.
authors.affiliation: Biology Department, New York University, New York 10003, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Wysocka-Diller
authors.forename: P N
authors.initials: PN
authors.lastname: Benfey
mesh_terms: D017360:Arabidopsis / Q000196:embryology / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins; D002454:Cell Differentiation; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D008954:Models, Biological; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics; D018517:Plant Roots / Q000254:growth & development*; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D010940:Plant Proteins; C100978:SCR protein, Arabidopsis