title: Plant development. Arabidopsis NAC45/86 direct sieve element morphogenesis culminating in enucleation.
abstract: Photoassimilates such as sugars are transported through phloem sieve element cells in plants. Adapted for effective transport, sieve elements develop as enucleated living cells. We used electron microscope imaging and three-dimensional reconstruction to follow sieve element morphogenesis in Arabidopsis. We show that sieve element differentiation involves enucleation, in which the nuclear contents are released and degraded in the cytoplasm at the same time as other organelles are rearranged and the cytosol is degraded. These cellular reorganizations are orchestrated by the genetically redundant NAC domain-containing transcription factors, NAC45 and NAC86 (NAC45/86). Among the NAC45/86 targets, we identified a family of genes required for enucleation that encode proteins with nuclease domains. Thus, sieve elements differentiate through a specialized autolysis mechanism.
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Kaori Miyashima
authors: KM
authors: Furuta
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Shri Ram
authors: SR
authors: Yadav
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Satu
authors: S
authors: Lehesranta
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Ilya
authors: I
authors: Belevich
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Shunsuke
authors: S
authors: Miyashima
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Jung-ok
authors: JO
authors: Heo
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Anne
authors: A
authors: Vatén
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Ove
authors: O
authors: Lindgren
authors: Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium. Department of Plant System Biology, VIB, Technologiepark 927, B-9052 Gent, Belgium.
authors: Bert
authors: B
authors: De Rybel
authors: Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium. Department of Plant System Biology, VIB, Technologiepark 927, B-9052 Gent, Belgium.
authors: Gert
authors: G
authors: Van Isterdael
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Panu
authors: P
authors: Somervuo
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Raffael
authors: R
authors: Lichtenberger
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Raquel
authors: R
authors: Rocha
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Siripong
authors: S
authors: Thitamadee
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Sari
authors: S
authors: Tähtiharju
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland.
authors: Petri
authors: P
authors: Auvinen
authors: Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052 Gent, Belgium. Department of Plant System Biology, VIB, Technologiepark 927, B-9052 Gent, Belgium.
authors: Tom
authors: T
authors: Beeckman
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland. yrjo.helariutta@slcu.cam.ac.uk eija.jokitalo@helsinki.fi.
authors: Eija
authors: E
authors: Jokitalo
authors: Institute of Biotechnology, Department of Biological and Environmental Sciences, University of Helsinki, FIN-00014, Finland. Cardiff University Cardiff School of Biosciences, The Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK. The Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge CB2 1LR, UK. yrjo.helariutta@slcu.cam.ac.uk eija.jokitalo@helsinki.fi.
authors: Ykä
authors: Y
authors: Helariutta
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000648:ultrastructure; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology*; D002467:Cell Nucleus / Q000378:metabolism* / Q000648:ultrastructure; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D021621:Imaging, Three-Dimensional; D008854:Microscopy, Electron; D009024:Morphogenesis / Q000235:genetics / Q000502:physiology*; D052585:Phloem / Q000254:growth & development* / Q000648:ultrastructure; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*
chemical_list: D029681:Arabidopsis Proteins; D014157:Transcription Factors