30
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Central Cell in Flowering Plants: Specification, Signaling, and Evolution

      review-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          During the reproduction of animals and lower plants, one sperm cell usually outcompetes the rivals to fertilize a single egg cell. But in flowering plants, two sperm cells fertilize the two adjacent dimorphic female gametes, the egg and central cell, respectively, to initiate the embryo and endosperm within a seed. The endosperm nourishes the embryo development and is also the major source of nutrition in cereals for humankind. Central cell as one of the key innovations of flowering plants is the biggest cell in the multicellular haploid female gametophyte (embryo sac). The embryo sac differentiates from the meiotic products through successive events of nuclear divisions, cellularization, and cell specification. Nowadays, accumulating lines of evidence are raveling multiple roles of the central cell rather than only the endosperm precursor. In this review, we summarize the current understanding on its cell fate specification, intercellular communication, and evolution. We also highlight some key unsolved questions for the further studies in this field.

          Related collections

          Most cited references93

          • Record: found
          • Abstract: found
          • Article: not found

          Plants send small RNAs in extracellular vesicles to fungal pathogen to silence virulence genes

          Some pathogens and pests deliver small RNAs (sRNAs) into host cells to suppress host immunity. Conversely, hosts also transfer sRNAs into pathogens and pests to inhibit their virulence. Although sRNA trafficking has been observed in a wide variety of interactions, how sRNAs are transferred, especially from hosts to pathogens/pests, is still unknown. Here we show that host Arabidopsis cells secrete exosome-like extracellular vesicles to deliver sRNAs into fungal pathogen Botrytis cinerea. These sRNA-containing vesicles accumulate at the infection sites and are taken up by the fungal cells. Transferred host sRNAs induce silencing of fungal genes critical for pathogenicity. Thus, Arabidopsis has adapted exosome-mediated cross-kingdom RNA interference as part of its immune responses during the evolutionary arms race with the pathogen.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Active DNA demethylation in plant companion cells reinforces transposon methylation in gametes.

            The Arabidopsis thaliana central cell, the companion cell of the egg, undergoes DNA demethylation before fertilization, but the targeting preferences, mechanism, and biological significance of this process remain unclear. Here, we show that active DNA demethylation mediated by the DEMETER DNA glycosylase accounts for all of the demethylation in the central cell and preferentially targets small, AT-rich, and nucleosome-depleted euchromatic transposable elements. The vegetative cell, the companion cell of sperm, also undergoes DEMETER-dependent demethylation of similar sequences, and lack of DEMETER in vegetative cells causes reduced small RNA-directed DNA methylation of transposons in sperm. Our results demonstrate that demethylation in companion cells reinforces transposon methylation in plant gametes and likely contributes to stable silencing of transposable elements across generations.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Epigenetic reprogramming in plant sexual reproduction.

              Epigenetic reprogramming consists of global changes in DNA methylation and histone modifications. In mammals, epigenetic reprogramming is primarily associated with sexual reproduction and occurs during both gametogenesis and early embryonic development. Such reprogramming is crucial not only to maintain genomic integrity through silencing transposable elements but also to reset the silenced status of imprinted genes. In plants, observations of stable transgenerational inheritance of epialleles have argued against reprogramming. However, emerging evidence supports that epigenetic reprogramming indeed occurs during sexual reproduction in plants and that it has a major role in maintaining genome integrity and a potential contribution to epiallelic variation.
                Bookmark

                Author and article information

                Contributors
                Journal
                Front Plant Sci
                Front Plant Sci
                Front. Plant Sci.
                Frontiers in Plant Science
                Frontiers Media S.A.
                1664-462X
                21 October 2020
                2020
                : 11
                : 590307
                Affiliations
                [1] 1State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences , Beijing, China
                [2] 2College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences , Beijing, China
                Author notes

                Edited by: Daisuke Maruyama, Yokohama City University, Japan

                Reviewed by: Anja Schmidt, Universität Heidelberg, Germany; Ayelen Mariana Distéfano, Universidad Nacional de Mar del Plata Mar del Plata, Argentina

                *Correspondence: Hong-Ju Li, hjli@ 123456genetics.ac.cn

                This article was submitted to Plant Development and EvoDevo, a section of the journal Frontiers in Plant Science

                Article
                10.3389/fpls.2020.590307
                7609669
                33193544
                adf34d61-c581-4301-a584-34bf421591fb
                Copyright © 2020 Li and Yang.

                This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

                History
                : 01 August 2020
                : 28 September 2020
                Page count
                Figures: 2, Tables: 1, Equations: 0, References: 93, Pages: 12, Words: 0
                Funding
                Funded by: National Natural Science Foundation of China 10.13039/501100001809
                Award ID: 31870295
                Award ID: 31991203
                Categories
                Plant Science
                Review

                Plant science & Botany
                central cell,double fertilization,flowering plants,gymnosperm,cell specification,cell-cell communication

                Comments

                Comment on this article