title: Divide et impera: boundaries shape the plant body and initiate new meristems.
abstract: 485 I. 485 II. 486 III. 491 IV. 491 V. 495 495 References 495 SUMMARY: Boundaries, established and maintained in different regions of the plant body, have diverse functions in development. One role is to separate different cell groups, for example the differentiating cells of a leaf primordium from the pluripotent cells of the apical meristem. Boundary zones are also established during compound leaf development, to separate young leaflets from each other, and in many other positions of the plant body. Recent studies have demonstrated that different boundary zones share similar properties. They are characterized by a low rate of cell divisions and specific patterns of gene expression. In addition, the levels of the plant hormones auxin and brassinosteroids are down-regulated in boundary zones, resulting in a low differentiation level of boundary cells. This feature seems to be crucial for a second important role of boundary zones, the formation of new meristems. The primary shoot meristem, as well as secondary and ectopic shoot meristems, initiate from boundary cells that exhibit competence for meristem formation.
authors.affiliation: Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829, Cologne, Germany.
authors.forename: Quan
authors.identifier: http://orcid.org/0000-0003-2912-1263
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829, Cologne, Germany.
authors.forename: Alice
authors.initials: A
authors.lastname: Hasson
authors.affiliation: Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829, Cologne, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Rossmann
authors.affiliation: Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829, Cologne, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Theres
mesh_terms: D060406:Brassinosteroids / Q000378:metabolism*; D002455:Cell Division; D018507:Gene Expression Regulation, Developmental; D007210:Indoleacetic Acids / Q000378:metabolism*; D018519:Meristem / Q000166:cytology / Q000235:genetics / Q000254:growth & development*; D018515:Plant Leaves / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D018520:Plant Shoots / Q000254:growth & development
chemical_list: D060406:Brassinosteroids; D007210:Indoleacetic Acids
keywords: Arabidopsis; axillary meristem; boundary zone; compound leaf; ectopic meristem; tomato (Solanum lycopersicum)