title: Chromatin organization and cell fate switch respond to positional information in Arabidopsis.
abstract: Many types of plant cell retain their developmental plasticity and have the capacity to switch fate when exposed to a new source of positional information. In the root epidermis of Arabidopsis, cells differentiate in alternating files of hair cells and non-hair cells, in response to positional information and the activity of the homoeodomain transcription factor GLABRA2 (GL2) in future non-hair cells. Here we show by three-dimensional fluorescence in situ hybridization on intact root epidermal tissue that alternative states of chromatin organization around the GL2 locus are required to control position-dependent cell-type specification. When, as a result of an atypical cell division, a cell is displaced from a hair file into a non-hair file, it switches fate. We show that during this event the chromatin state around the GL2 locus is not inherited, but is reorganized in the G1 phase of the cell cycle in response to local positional information. This ability to remodel chromatin organization may provide the basis for the plasticity in plant cell fate changes.
authors.affiliation: Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK.
authors.forename: Silvia
authors.initials: S
authors.lastname: Costa
authors.forename: Peter
authors.initials: P
authors.lastname: Shaw
mesh_terms: D017360:Arabidopsis / Q000033:anatomy & histology* / Q000166:cytology* / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation; D002455:Cell Division; D019070:Cell Lineage; D002843:Chromatin / Q000235:genetics* / Q000378:metabolism*; D042002:Chromatin Assembly and Disassembly; D004268:DNA-Binding Proteins / Q000235:genetics; D016193:G1 Phase; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D017404:In Situ Hybridization, Fluorescence; D018519:Meristem / Q000166:cytology / Q000378:metabolism; D009928:Organ Specificity; D019441:Plant Epidermis / Q000166:cytology / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics; D018517:Plant Roots / Q000166:cytology; D020598:Proto-Oncogene Proteins c-myb / Q000235:genetics
chemical_list: C511988:ATR1 protein, Arabidopsis; D029681:Arabidopsis Proteins; C511989:CPC protein, Arabidopsis; D002843:Chromatin; D004268:DNA-Binding Proteins; C422044:FAS protein, Arabidopsis; C089991:GL2 protein, Arabidopsis; D018398:Homeodomain Proteins; D010940:Plant Proteins; D020598:Proto-Oncogene Proteins c-myb; C402111:WER protein, Arabidopsis