title: Organizer-Derived WOX5 Signal Maintains Root Columella Stem Cells through Chromatin-Mediated Repression of CDF4 Expression.
abstract: Stem cells in plants and animals are maintained pluripotent by signals from adjacent niche cells. In plants, WUSCHEL HOMEOBOX (WOX) transcription factors are central regulators of stem cell maintenance in different meristem types, yet their molecular mode of action has remained elusive. Here we show that in the Arabidopsis root meristem, the WOX5 protein moves from the root niche organizer, the quiescent center, into the columella stem cells, where it directly represses the transcription factor gene CDF4. This creates a gradient of CDF4 transcription, which promotes differentiation opposite to the WOX5 gradient, allowing stem cell daughter cells to exit the stem cell state. We further show that WOX5 represses CDF4 transcription by recruiting TPL/TPR co-repressors and the histone deacetylase HDA19, which consequently induces histone deacetylation at the CDF4 regulatory region. Our results show that chromatin-mediated repression of differentiation programs is a common strategy in plant and animal stem cell niches.
authors.affiliation: BIOSS Centre for Biological Signalling Studies, Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany.
authors.forename: Limin
authors.initials: L
authors.lastname: Pi
authors.affiliation: BIOSS Centre for Biological Signalling Studies, Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany.
authors.forename: Ernst
authors.initials: E
authors.lastname: Aichinger
authors.affiliation: BIOSS Centre for Biological Signalling Studies, Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany.
authors.forename: Eric
authors.initials: E
authors.lastname: van der Graaff
authors.affiliation: Laboratory of Biochemistry, Wageningen University, Dreijenlaan 3, 6703HA Wageningen, the Netherlands.
authors.forename: Cristina I
authors.initials: CI
authors.lastname: Llavata-Peris
authors.affiliation: Laboratory of Biochemistry, Wageningen University, Dreijenlaan 3, 6703HA Wageningen, the Netherlands.
authors.forename: Dolf
authors.initials: D
authors.lastname: Weijers
authors.affiliation: Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007 Uppsala, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Hennig
authors.affiliation: BIOSS Centre for Biological Signalling Studies, Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany.
authors.forename: Edwin
authors.initials: E
authors.lastname: Groot
authors.affiliation: BIOSS Centre for Biological Signalling Studies, Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany. Electronic address: laux@biologie.uni-freiburg.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Laux
mesh_terms: D000107:Acetylation; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002454:Cell Differentiation; D002843:Chromatin / Q000235:genetics*; D047369:Chromatin Immunoprecipitation; D056970:Co-Repressor Proteins / Q000235:genetics / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D017403:In Situ Hybridization; D018519:Meristem / Q000166:cytology* / Q000378:metabolism; D046228:Microarray Analysis; D018613:Microscopy, Confocal; D028861:Nuclear Pore Complex Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D015398:Signal Transduction; D055153:Stem Cell Niche; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D002843:Chromatin; D056970:Co-Repressor Proteins; D006655:Histone Deacetylases; D006657:Histones; D018398:Homeodomain Proteins; D028861:Nuclear Pore Complex Proteins; C524167:TPR protein, Arabidopsis; C116421:WUSCHEL protein, Arabidopsis; C511291:At1g15750 protein, Arabidopsis; C507152:HDA19 protein, Arabidopsis