title: PRC2 represses dedifferentiation of mature somatic cells in Arabidopsis.
abstract: Plant somatic cells are generally acknowledged to retain totipotency, the potential to develop into any cell type within an organism. This astonishing plasticity may contribute to a high regenerative capacity on severe damage, but how plants control this potential during normal post-embryonic development remains largely unknown(1,2). Here we show that POLYCOMB REPRESSIVE COMPLEX 2 (PRC2), a chromatin regulator that maintains gene repression through histone modification, prevents dedifferentiation of mature somatic cells in Arabidopsis thaliana roots. Loss-of-function mutants in PRC2 subunits initially develop unicellular root hairs indistinguishable from those in wild type but fail to retain the differentiated state, ultimately resulting in the generation of an unorganized cell mass and somatic embryos from a single root hair. Strikingly, mutant root hairs complete the normal endoreduplication programme, increasing their nuclear ploidy, but subsequently reinitiate mitotic division coupled with successive DNA replication. Our data show that the WOUND INDUCED DEDIFFERENTIATION3 (WIND3) and LEAFY COTYLEDON2 (LEC2) genes are among the PRC2 targets involved in this reprogramming, as their ectopic overexpression partly phenocopies the dedifferentiation phenotype of PRC2 mutants. These findings unveil the pivotal role of PRC2-mediated gene repression in preventing unscheduled reprogramming of fully differentiated plant cells.
authors.affiliation: RIKEN Centre for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Momoko
authors.initials: M
authors.lastname: Ikeuchi
authors.affiliation: RIKEN Centre for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Iwase
authors.affiliation: RIKEN Centre for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Bart
authors.initials: B
authors.lastname: Rymen
authors.affiliation: RIKEN Centre for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Harashima
authors.affiliation: RIKEN Centre for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Michitaro
authors.initials: M
authors.lastname: Shibata
authors.affiliation: RIKEN Centre for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Ohnuma
authors.affiliation: RIKEN Centre for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Christian
authors.initials: C
authors.lastname: Breuer
authors.affiliation: Institut de Biologie de l'Ecole Normale Supérieure, CNRS UMR8197, INSERM U1024, 46 rue d'Ulm, Paris Cedex 05 75230, France.
authors.forename: Ana Karina
authors.initials: AK
authors.lastname: Morao
authors.affiliation: Department of Plant Biology and Genome Center, University of California, Davis, 1002 Life Sciences, One Shields Avenue, Davis, California 95616, USA.
authors.forename: Miguel
authors.initials: M
authors.lastname: de Lucas
authors.affiliation: Department of Plant Systems Biology, VIB, Gent B-9052, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, Gent B-9052, Belgium.
authors.forename: Lieven
authors.initials: L
authors.lastname: De Veylder
authors.affiliation: Institute of Molecular Plant Sciences, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JR, UK.
authors.forename: Justin
authors.initials: J
authors.lastname: Goodrich
authors.affiliation: Department of Plant Biology and Genome Center, University of California, Davis, 1002 Life Sciences, One Shields Avenue, Davis, California 95616, USA.
authors.forename: Siobhan M
authors.initials: SM
authors.lastname: Brady
authors.affiliation: Institut de Biologie de l'Ecole Normale Supérieure, CNRS UMR8197, INSERM U1024, 46 rue d'Ulm, Paris Cedex 05 75230, France.
authors.forename: François
authors.identifier: http://orcid.org/0000-0002-1757-6386
authors.initials: F
authors.lastname: Roudier
authors.affiliation: RIKEN Centre for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Sugimoto