title: Quiescent center initiation in the Arabidopsis lateral root primordia is dependent on the SCARECROW transcription factor.
abstract: Lateral root formation is an important determinant of root system architecture. In Arabidopsis, lateral roots originate from pericycle cells, which undergo a program of morphogenesis to generate a new lateral root meristem. Despite its importance for root meristem organization, the onset of quiescent center (QC) formation during lateral root morphogenesis remains unclear. Here, we used live 3D confocal imaging to monitor cell organization and identity acquisition during lateral root development. Our dynamic observations revealed an early morphogenesis phase and a late meristem formation phase as proposed in the bi-phasic growth model. Establishment of lateral root QCs coincided with this developmental phase transition. QC precursor cells originated from the outer layer of stage II lateral root primordia, within which the SCARECROW (SCR) transcription factor was specifically expressed. Disrupting SCR function abolished periclinal divisions in this lateral root primordia cell layer and perturbed the formation of QC precursor cells. We conclude that de novo QC establishment in lateral root primordia operates via SCR-mediated formative cell division and coincides with the developmental phase transition.
authors: Department of Biology, Graduate School of Science, Kobe University, Kobe 657-8501, Japan Centre for Plant Integrative Biology, School of Biosciences, University of Nottingham, Nottingham LE12 5RD, UK goh@bs.naist.jp soazig.guyomarch@ird.fr.
authors: Tatsuaki
authors: 0000-0002-1064-5801
authors: T
authors: Goh
authors: Department of Biology, Graduate School of Science, Kobe University, Kobe 657-8501, Japan.
authors: Koichi
authors: K
authors: Toyokura
authors: Centre for Plant Integrative Biology, School of Biosciences, University of Nottingham, Nottingham LE12 5RD, UK.
authors: Darren M
authors: DM
authors: Wells
authors: Centre for Plant Integrative Biology, School of Biosciences, University of Nottingham, Nottingham LE12 5RD, UK.
authors: Kamal
authors: K
authors: Swarup
authors: Department of Biology, Graduate School of Science, Kobe University, Kobe 657-8501, Japan.
authors: Mayuko
authors: M
authors: Yamamoto
authors: Department of Biology, Graduate School of Science, Kobe University, Kobe 657-8501, Japan.
authors: Tetsuro
authors: T
authors: Mimura
authors: Laboratory of Biochemistry, Wageningen University, 6703 HA Wageningen, The Netherlands.
authors: Dolf
authors: D
authors: Weijers
authors: Department of Biology, Graduate School of Science, Kobe University, Kobe 657-8501, Japan.
authors: Hidehiro
authors: H
authors: Fukaki
authors: Institut de Recherche pour le Développement, Unité Mixte de Recherche (UMR) Diversité Adaptation et Développement des plantes (DIADE), Montpellier 34394 Cedex 5, France.
authors: Laurent
authors: L
authors: Laplaze
authors: Centre for Plant Integrative Biology, School of Biosciences, University of Nottingham, Nottingham LE12 5RD, UK.
authors: Malcolm J
authors: MJ
authors: Bennett
authors: Université de Montpellier, Unité Mixte de Recherche (UMR) Diversité Adaptation et Développement des plantes (DIADE), Montpellier 34394 Cedex 5, France goh@bs.naist.jp soazig.guyomarch@ird.fr.
authors: Soazig
authors: S
authors: Guyomarc'h
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018519:Meristem / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C100978:SCR protein, Arabidopsis
keywords: 3D live imaging; Arabidopsis thaliana; Lateral root organogenesis; Quiescent center; SCARECROW