title: Control of Arabidopsis lateral root primordium boundaries by MYB36.
abstract: Root branching in plants relies on the de novo formation of lateral roots. These are initiated from founder cells, triggering new formative divisions that generate lateral root primordia (LRP). The LRP size and shape depends on the balance between positive and negative signals that control cell proliferation. The mechanisms controlling proliferation potential of LRP cells remains poorly understood. We found that Arabidopsis thaliana MYB36, which have been previously shown to regulate genes required for Casparian strip formation and the transition from proliferation to differentiation in the primary root, plays a new role in controlling LRP development at later stages. We found that MYB36 is a novel component of LR development at later stages. MYB36 was expressed in the cells surrounding LRP where it controls a set of peroxidase genes, which maintain reactive oxygen species (ROS) balance. This was required to define the transition between proliferating and arrested cells inside the LRP, coinciding with the change from flat to dome-shaped primordia. Reducing the levels of hydrogen peroxide (H2O2) in myb36-5 significantly rescues the mutant phenotype. Our results uncover a role for MYB36 outside the endodermis during LRP development through a mechanism analogous to regulating the proliferation/differentiation transition in the root meristem.
authors.affiliation: Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolas Cabrera 1, 28049, Madrid, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Fernández-Marcos
authors.affiliation: Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolas Cabrera 1, 28049, Madrid, Spain.
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Desvoyes
authors.affiliation: Centro de Biotecnología y Genómica de Plantas, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, Pozuelo de Alarcón, 28223, Madrid, Spain.
authors.forename: Concepción
authors.initials: C
authors.lastname: Manzano
authors.affiliation: Howard Hughes Medical Institute and Department of Biology, Duke University, Durham, NC, 27708, USA.
authors.forename: Louisa M
authors.initials: LM
authors.lastname: Liberman
authors.affiliation: Howard Hughes Medical Institute and Department of Biology, Duke University, Durham, NC, 27708, USA.
authors.forename: Philip N
authors.initials: PN
authors.lastname: Benfey
authors.affiliation: Centro de Biotecnología y Genómica de Plantas, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, Pozuelo de Alarcón, 28223, Madrid, Spain.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Del Pozo
authors.affiliation: Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Nicolas Cabrera 1, 28049, Madrid, Spain.
authors.forename: Crisanto
authors.identifier: 0000-0001-8905-8222
authors.initials: C
authors.lastname: Gutierrez
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D049109:Cell Proliferation; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D006706:Homeostasis; D018517:Plant Roots / Q000033:anatomy & histology / Q000166:cytology / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C000602970:MYB36 protein, Arabidopsis; D017382:Reactive Oxygen Species; D014157:Transcription Factors
keywords: Arabidopsis; Casparian strip; MYB36; cell division; lateral root; peroxidase; plant; transcription factor