1
|
Rolletschek H, Muszynska A, Schwender J, Radchuk V, Heinemann B, Hilo A, Plutenko I, Keil P, Ortleb S, Wagner S, Kalms L, Gündel A, Shi H, Fuchs J, Szymanski JJ, Braun HP, Borisjuk L. Mechanical forces orchestrate the metabolism of the developing oilseed rape embryo. THE NEW PHYTOLOGIST 2024. [PMID: 39044722 DOI: 10.1111/nph.19990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Accepted: 06/18/2024] [Indexed: 07/25/2024]
Abstract
The initial free expansion of the embryo within a seed is at some point inhibited by its contact with the testa, resulting in its formation of folds and borders. Although less obvious, mechanical forces appear to trigger and accelerate seed maturation. However, the mechanistic basis for this effect remains unclear. Manipulation of the mechanical constraints affecting either the in vivo or in vitro growth of oilseed rape embryos was combined with analytical approaches, including magnetic resonance imaging and computer graphic reconstruction, immunolabelling, flow cytometry, transcriptomic, proteomic, lipidomic and metabolomic profiling. Our data implied that, in vivo, the imposition of mechanical restraints impeded the expansion of testa and endosperm, resulting in the embryo's deformation. An acceleration in embryonic development was implied by the cessation of cell proliferation and the stimulation of lipid and protein storage, characteristic of embryo maturation. The underlying molecular signature included elements of cell cycle control, reactive oxygen species metabolism and transcriptional reprogramming, along with allosteric control of glycolytic flux. Constricting the space allowed for the expansion of in vitro grown embryos induced a similar response. The conclusion is that the imposition of mechanical constraints over the growth of the developing oilseed rape embryo provides an important trigger for its maturation.
Collapse
Affiliation(s)
- Hardy Rolletschek
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| | - Aleksandra Muszynska
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
- Amatera Biosciences, 4 rue Pierre Fontaine, Evry, 91000, France
| | - Jörg Schwender
- Biology Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Volodymyr Radchuk
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| | - Björn Heinemann
- Institut für Pflanzengenetik, Universität Hannover, Herrenhäuser Strasse, Hannover, 30419, Germany
| | - Alexander Hilo
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| | - Iaroslav Plutenko
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| | - Peter Keil
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| | - Stefan Ortleb
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| | - Steffen Wagner
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| | - Laura Kalms
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| | - André Gündel
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
- Department of Ecology, Environment and Plant Sciences, University of Stockholm, Stockholm, 10691, Sweden
| | - Hai Shi
- Biology Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Jörg Fuchs
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| | - Jedrzej Jakub Szymanski
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
- Institute of Bio- and Geosciences, IBG-4: Bioinformatics, Forschungszentrum Jülich, Jülich, D-52428, Germany
- Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich-Heine-Universität Düsseldorf, Düsseldorf, 40225, Germany
| | - Hans-Peter Braun
- Institut für Pflanzengenetik, Universität Hannover, Herrenhäuser Strasse, Hannover, 30419, Germany
| | - Ljudmilla Borisjuk
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland, OT Gatersleben, 06466, Germany
| |
Collapse
|
2
|
Harnvanichvech Y, Borassi C, Daghma DES, van der Kooij HM, Sprakel J, Weijers D. An elastic proteinaceous envelope encapsulates the early Arabidopsis embryo. Development 2023; 150:dev201943. [PMID: 37869985 PMCID: PMC10651100 DOI: 10.1242/dev.201943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 10/09/2023] [Indexed: 10/24/2023]
Abstract
Plant external surfaces are often covered by barriers that control the exchange of molecules, protect from pathogens and offer mechanical integrity. A key question is when and how such surface barriers are generated. Post-embryonic surfaces have well-studied barriers, including the cuticle, and it has been previously shown that the late Arabidopsis thaliana embryo is protected by an endosperm-derived sheath deposited onto a primordial cuticle. Here, we show that both cuticle and sheath are preceded by another structure during the earliest stages of embryogenesis. This structure, which we named the embryonic envelope, is tightly wrapped around the embryonic surface but can be physically detached by cell wall digestion. We show that this structure is composed primarily of extensin and arabinogalactan O-glycoproteins and lipids, which appear to form a dense and elastic crosslinked embryonic envelope. The envelope forms in cuticle-deficient mutants and in a mutant that lacks endosperm. This embryo-derived envelope is therefore distinct from previously described cuticle and sheath structures. We propose that it acts as an expandable diffusion barrier, as well as a means to mechanically confine the embryo to maintain its tensegrity during early embryogenesis.
Collapse
Affiliation(s)
- Yosapol Harnvanichvech
- Laboratory of Biochemistry, Wageningen University and Research, Wageningen 6708 WE, The Netherlands
- Physical Chemistry and Soft Matter, Wageningen University and Research, Wageningen 6708 WE, The Netherlands
| | - Cecilia Borassi
- Laboratory of Biochemistry, Wageningen University and Research, Wageningen 6708 WE, The Netherlands
| | - Diaa Eldin S. Daghma
- Laboratory of Biochemistry, Wageningen University and Research, Wageningen 6708 WE, The Netherlands
| | - Hanne M. van der Kooij
- Physical Chemistry and Soft Matter, Wageningen University and Research, Wageningen 6708 WE, The Netherlands
| | - Joris Sprakel
- Laboratory of Biochemistry, Wageningen University and Research, Wageningen 6708 WE, The Netherlands
| | - Dolf Weijers
- Laboratory of Biochemistry, Wageningen University and Research, Wageningen 6708 WE, The Netherlands
| |
Collapse
|
3
|
Doll NM, Truskina J, Ingram G. Functional and developmental convergence in the reproductive "nurse cells" of flowering plants. C R Biol 2023; 346:45-54. [PMID: 37254742 DOI: 10.5802/crbiol.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 04/13/2023] [Accepted: 04/13/2023] [Indexed: 06/01/2023]
Abstract
The successful sexual reproduction of flowering plants depends upon double fertilisation, during which pollen grains, produced within the male floral organ (the anther) deliver two sperm cells to the ovule, buried deep within the ovary, triggering the development of the embryo and the surrounding tissues of the seed. Although much attention has been given to pollen and embryo development, less has been focused on the supporting tissues surrounding these organisms as they develop, the tapetum and the endosperm. Intriguingly, despite their very different origins, these tissues appear to have converged functionally and developmentally. Here we will discuss this apparent convergence and its molecular and physiological basis.
Collapse
|
4
|
Ali O, Cheddadi I, Landrein B, Long Y. Revisiting the relationship between turgor pressure and plant cell growth. THE NEW PHYTOLOGIST 2023; 238:62-69. [PMID: 36527246 DOI: 10.1111/nph.18683] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
Growth is central to plant morphogenesis. Plant cells are encased in rigid cell walls, and they must overcome physical confinement to grow to specific sizes and shapes. Cell wall tension and turgor pressure are the main mechanical components impacting plant cell growth. Cell wall mechanics has been the focus of most plant biomechanical studies, and turgor pressure was often considered as a constant and largely passive component. Nevertheless, it is increasingly accepted that turgor pressure plays a significant role in plant growth. Numerous theoretical and experimental studies suggest that turgor pressure can be both spatially inhomogeneous and actively modulated during morphogenesis. Here, we revisit the pressure-growth relationship by reviewing recent advances in investigating the interactions between cellular/tissular pressure and growth.
Collapse
Affiliation(s)
- Olivier Ali
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Lyon Cedex 07, 69364, France
| | - Ibrahim Cheddadi
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Lyon Cedex 07, 69364, France
- Univ. Grenoble Alpes, CNRS, UMR 5525, VetAgro Sup, Grenoble INP, TIMC, 38000, Grenoble, France
| | - Benoit Landrein
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Lyon Cedex 07, 69364, France
| | - Yuchen Long
- Department of Biological Sciences, The National University of Singapore, Singapore, 117543, Singapore
- Mechanobiology Institute, The National University of Singapore, Singapore, 117411, Singapore
| |
Collapse
|
5
|
Li C, Hu F, Chen H, Zhao J. Transcriptome characteristics during cell wall formation of endosperm cellularization and embryo differentiation in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2022; 13:998664. [PMID: 36262665 PMCID: PMC9575994 DOI: 10.3389/fpls.2022.998664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Embryonic and endosperm development are important biological events during Arabidopsis seed development, and are controlled by dynamic changes in a range of gene expression. Nevertheless, the regulatory mechanisms of endosperm cellularization and embryo differentiation remain unclear. Here, we characterized the early embryo and endosperm development of the naa15 mutant that had abnormal embryo differentiation and incomplete endosperm cellularization compared to WT of Arabidopsis, and comparatively investigated the changes of gene expressions in WT seeds at 3, 4, and 5 days after pollination (3W, 4W, and 5W) and the white homozygous aborted naa15 seeds at 5, 6, and 7 DAP (5M, 6M, and 7M) from naa15-1/+ siliques using RNA sequencing and qPCR assays. The transcriptome analyses showed that there were 2040 and 3630 differentially expressed genes (DEGs) in 4W (at endosperm cellularization initiation stage and heart embryo stage) vs 3W (at syncytium stage and globular embryo stage), and 5W (at end of endosperm cellularization stage and torpedo embryo stage) vs 4W, respectively. The KEGG and GO analyses showed that lipid metabolic processes and transmembrane transport related to cell wall biogenesis, cell division and differentiation, the plant hormone signaling pathway, photosynthesis, and transcription regulator activity were evidently enriched in WT and naa15. The heatmap and qPCR analyses showed that auxin response genes (ARFs), auxin transport genes (PINs) cytokinin synthesis genes (LOGs), cytokinin dehydrogenase genes (CKXs), cytokinin receptor, transcription factors (MYB, bHLH, MADS-box, and ERF) were significantly downregulated in naa15 compared to WT. A series of cell wall genes annotated to xyloglucan endotransglycosylase/hydrolase, pectin methyl esterase, and pectin methyl esterase inhibitor were also identified in these DEGs. Moreover, using an immunofluorescent assay, the features of cell walls displayed that cellulose fluorescence signals in the embryo and endosperm of naa15 were significantly decreased, and the signals of low- and high- methyl esterification of pectin were also obviously decreased in the endosperm of naa15. In summary, we identified a large number of DEGs and investigated the features of cell walls during endosperm cellularization and embryonic differentiation, which provided important information on transcription and gene expression to reveal their regulatory mechanisms.
Collapse
|
6
|
Zhang H, Li X, Wang W, Li H, Cui Y, Zhu Y, Kui H, Yi J, Li J, Gou X. SERKs regulate embryonic cuticle integrity through the TWS1-GSO1/2 signaling pathway in Arabidopsis. THE NEW PHYTOLOGIST 2022; 233:313-328. [PMID: 34614228 DOI: 10.1111/nph.17775] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 09/25/2021] [Indexed: 06/13/2023]
Abstract
The embryonic cuticle integrity is critical for the embryo to separate from the neighboring endosperm. The sulfated TWISTED SEED1 (TWS1) peptide precursor generated in the embryo diffuses through gaps of the nascent cuticle to the surrounding endosperm, where it is cleaved by ABNORMAL LEAF SHAPE1 (ALE1) and becomes an active mature form. The active TWS1 is perceived by receptor-like protein kinases GASSHO1 (GSO1) and GSO2 in the embryonic epidermal cells to start the downstream signaling and guide the formation of an intact embryonic cuticle. However, the early signaling events after TWS1 is perceived by GSO1/2 are still unknown. Here, we report that serk1/2/3 embryos show cuticle defects similar to ale1, tws1, and gso1/2. Genetic and biochemical analyses were performed to dissect the signaling pathway mediated by SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASEs (SERKs) during cuticle development. SERKs function with GSO1/2 in a common pathway to monitor the integrity of the embryonic cuticle. SERKs interact with GSO1/2, which can be enhanced dramatically by TWS1. The phosphorylation levels of SERKs and GSO1/2 rely on each other and can respond to and be elevated by TWS1. Our results demonstrate that SERKs may function as coreceptors of GSO1/2 to transduce the TWS1 signal and ultimately regulate embryonic cuticle integrity.
Collapse
Affiliation(s)
- Hong Zhang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Xiaonan Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Wenping Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Huiqiang Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Yanwei Cui
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Yafen Zhu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Hong Kui
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Jing Yi
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Jia Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Xiaoping Gou
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| |
Collapse
|
7
|
Song J, Xie X, Cui Y, Zou J. Endosperm-Embryo Communications: Recent Advances and Perspectives. PLANTS (BASEL, SWITZERLAND) 2021; 10:plants10112511. [PMID: 34834874 PMCID: PMC8625250 DOI: 10.3390/plants10112511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 05/22/2023]
Abstract
Seed maturation depends on well-coordinated communications between the processes of endosperm and embryo development. The endosperm is considered to be destined to support embryo development and the timing of endosperm cellularization is critical for embryo growth. Recent findings suggest that the endosperm development and the onset of embryo maturation are two independent processes during seed development. Meanwhile, it is lately reported that several mobile regulators originating from the endosperm are needed to ensure proper embryo growth and seed maturation. In this opinion article, we highlight processes on how endosperm communicates with embryo during seed development and discuss some intriguing questions in light of the latest advancements.
Collapse
Affiliation(s)
- Jingpu Song
- Aquatic and Crop Resource Development Research Centre, National Research Council of Canada, Saskatoon, SK S7N 0W9, Canada;
- Correspondence:
| | - Xin Xie
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON N5V 4T3, Canada; (X.X.); (Y.C.)
- Department of Biology, Western University, London, ON N6A 3K7, Canada
| | - Yuhai Cui
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON N5V 4T3, Canada; (X.X.); (Y.C.)
- Department of Biology, Western University, London, ON N6A 3K7, Canada
| | - Jitao Zou
- Aquatic and Crop Resource Development Research Centre, National Research Council of Canada, Saskatoon, SK S7N 0W9, Canada;
| |
Collapse
|
8
|
Sharma P, Gayen D. Plant protease as regulator and signaling molecule for enhancing environmental stress-tolerance. PLANT CELL REPORTS 2021; 40:2081-2095. [PMID: 34173047 DOI: 10.1007/s00299-021-02739-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
Proteases are ubiquitous in prokaryotes and eukaryotes. Plant proteases are key regulators of various physiological processes, including protein homeostasis, organelle development, senescence, seed germination, protein processing, environmental stress response, and programmed cell death. Proteases are involved in the breakdown of peptide bonds resulting in irreversible posttranslational modification of the protein. Proteases act as signaling molecules that specifically regulate cellular function by cleaving and triggering receptor molecules. Peptides derived from proteolysis regulate ROS signaling under oxidative stress in the plant. It degrades misfolded and abnormal proteins into amino acids to repair the cell damage and regulates the biological process in response to environmental stress. Proteases modulate the biogenesis of phytohormones which control plant growth, development, and environmental stresses. Protein homeostasis, the overall balance between protein synthesis and proteolysis, is required for plant growth and development. Abiotic and biotic stresses are major factors that negatively impact cellular survivability, biomass production, and reduced crop yield potentials. Therefore, the identification of various stress-responsive proteases and their molecular functions may elucidate valuable information for the development of stress-resilient crops with higher yield potentials. However, the understanding of molecular mechanisms of plant protease remains unexplored. This review provides an overview of proteases related to development, signaling, and growth regulation to acclimatize environmental stress in plants.
Collapse
Affiliation(s)
- Punam Sharma
- Department of Biochemistry, Central University of Rajasthan, Ajmer, 305817, Rajasthan, India
| | - Dipak Gayen
- Department of Biochemistry, Central University of Rajasthan, Ajmer, 305817, Rajasthan, India.
| |
Collapse
|
9
|
Shevtsov-Tal S, Best C, Matan R, Chandran SA, Brown GG, Ostersetzer-Biran O. nMAT3 is an essential maturase splicing factor required for holo-complex I biogenesis and embryo development in Arabidopsis thaliana plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:1128-1147. [PMID: 33683754 DOI: 10.1111/tpj.15225] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 02/25/2021] [Accepted: 03/01/2021] [Indexed: 05/21/2023]
Abstract
Group-II introns are self-splicing mobile genetic elements consisting of catalytic intron-RNA and its related intron-encoded splicing maturase protein cofactor. Group-II sequences are particularly plentiful within the mitochondria of land plants, where they reside within many critical gene loci. During evolution, the plant organellar introns have degenerated, such as they lack regions that are are required for splicing, and also lost their evolutionary related maturase proteins. Instead, for their splicing the organellar introns in plants rely on different host-acting protein cofactors, which may also provide a means to link cellular signals with respiratory functions. The nuclear genome of Arabidopsis thaliana encodes four maturase-related factors. Previously, we showed that three of the maturases, nMAT1, nMAT2 and nMAT4, function in the excision of different group-II introns in Arabidopsis mitochondria. The function of nMAT3 (encoded by the At5g04050 gene locus) was found to be essential during early embryogenesis. Using a modified embryo-rescue method, we show that nMAT3-knockout plants are strongly affected in the splicing of nad1 introns 1, 3 and 4 in Arabidopsis mitochondria, resulting in complex-I biogenesis defects and altered respiratory activities. Functional complementation of nMAT3 restored the organellar defects and embryo-arrested phenotypes associated with the nmat3 mutant line. Notably, nMAT3 and nMA4 were found to act on the same RNA targets but have no redundant functions in the splicing of nad1 transcripts. The two maturases, nMAT3 and nMAT4 are likely to cooperate together in the maturation of nad1 pre-RNAs. Our results provide important insights into the roles of maturases in mitochondria gene expression and the biogenesis of the respiratory system during early plant life.
Collapse
Affiliation(s)
- Sofia Shevtsov-Tal
- Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Givat-Ram, Jerusalem, 91904, Israel
| | - Corinne Best
- Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Givat-Ram, Jerusalem, 91904, Israel
| | - Roei Matan
- Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Givat-Ram, Jerusalem, 91904, Israel
| | - Sam A Chandran
- School of Chemical and Biotechnology, SASTRA University, Thanjavur, 613 401, India
| | - Gregory G Brown
- Department of Biology, McGill University, Montreal, Quebec, H3A 1B1, Canada
| | - Oren Ostersetzer-Biran
- Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Givat-Ram, Jerusalem, 91904, Israel
| |
Collapse
|
10
|
Dai D, Ma Z, Song R. Maize endosperm development. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:613-627. [PMID: 33448626 DOI: 10.1111/jipb.13069] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 01/12/2021] [Indexed: 05/22/2023]
Abstract
Recent breakthroughs in transcriptome analysis and gene characterization have provided valuable resources and information about the maize endosperm developmental program. The high temporal-resolution transcriptome analysis has yielded unprecedented access to information about the genetic control of seed development. Detailed spatial transcriptome analysis using laser-capture microdissection has revealed the expression patterns of specific populations of genes in the four major endosperm compartments: the basal endosperm transfer layer (BETL), aleurone layer (AL), starchy endosperm (SE), and embryo-surrounding region (ESR). Although the overall picture of the transcriptional regulatory network of endosperm development remains fragmentary, there have been some exciting advances, such as the identification of OPAQUE11 (O11) as a central hub of the maize endosperm regulatory network connecting endosperm development, nutrient metabolism, and stress responses, and the discovery that the endosperm adjacent to scutellum (EAS) serves as a dynamic interface for endosperm-embryo crosstalk. In addition, several genes that function in BETL development, AL differentiation, and the endosperm cell cycle have been identified, such as ZmSWEET4c, Thk1, and Dek15, respectively. Here, we focus on current advances in understanding the molecular factors involved in BETL, AL, SE, ESR, and EAS development, including the specific transcriptional regulatory networks that function in each compartment during endosperm development.
Collapse
Affiliation(s)
- Dawei Dai
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
- Shanghai Key Laboratory of Bio-Energy Crops, Plant Science Center, School of Life Sciences, Shanghai University, Shanghai, 200444, China
| | - Zeyang Ma
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Rentao Song
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| |
Collapse
|
11
|
Sheldrake AR. The production of auxin by dying cells. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:2288-2300. [PMID: 33460445 DOI: 10.1093/jxb/erab009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 01/13/2021] [Indexed: 05/12/2023]
Abstract
In this review, I discuss the possibility that dying cells produce much of the auxin in vascular plants. The natural auxin, indole-3-acetic acid (IAA), is derived from tryptophan by a two-step pathway via indole pyruvic acid. The first enzymes in the pathway, tryptophan aminotransferases, have a low affinity for tryptophan and break it down only when tryptophan levels rise far above normal intracellular concentrations. Such increases occur when tryptophan is released from proteins by hydrolytic enzymes as cells autolyse and die. Many sites of auxin production are in and around dying cells: in differentiating tracheary elements; in root cap cells; in nutritive tissues that break down in developing flowers and seeds; in senescent leaves; and in wounds. Living cells also produce auxin, such as those transformed genetically by the crown gall pathogen. IAA may first have served as an exogenous indicator of the presence of nutrient-rich decomposing organic matter, stimulating the production of rhizoids in bryophytes. As cell death was internalized in bryophytes and in vascular plants, IAA may have taken on a new role as an endogenous hormone.
Collapse
|
12
|
Rolletschek H, Muszynska A, Borisjuk L. The process of seed maturation is influenced by mechanical constraints. THE NEW PHYTOLOGIST 2021; 229:19-23. [PMID: 32735708 DOI: 10.1111/nph.16815] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Accepted: 07/09/2020] [Indexed: 06/11/2023]
Affiliation(s)
- Hardy Rolletschek
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland-Gatersleben, 06466, Germany
| | - Aleksandra Muszynska
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland-Gatersleben, 06466, Germany
| | - Ljudmilla Borisjuk
- Leibniz-Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, Seeland-Gatersleben, 06466, Germany
| |
Collapse
|
13
|
Escamez S, André D, Sztojka B, Bollhöner B, Hall H, Berthet B, Voß U, Lers A, Maizel A, Andersson M, Bennett M, Tuominen H. Cell Death in Cells Overlying Lateral Root Primordia Facilitates Organ Growth in Arabidopsis. Curr Biol 2020; 30:455-464.e7. [PMID: 31956028 DOI: 10.1016/j.cub.2019.11.078] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/22/2019] [Accepted: 11/26/2019] [Indexed: 02/06/2023]
Abstract
Plant organ growth is widely accepted to be determined by cell division and cell expansion, but, unlike that in animals, the contribution of cell elimination has rarely been recognized. We investigated this paradigm during Arabidopsis lateral root formation, when the lateral root primordia (LRP) must traverse three overlying cell layers within the parent root. A subset of LRP-overlying cells displayed the induction of marker genes for cell types undergoing developmental cell death, and their cell death was detected by electron, confocal, and light sheet microscopy techniques. LRP growth was delayed in cell-death-deficient mutants lacking the positive cell death regulator ORESARA1/ANAC092 (ORE1). LRP growth was restored in ore1-2 knockout plants by genetically inducing cell elimination in cells overlying the LRP or by physically killing LRP-overlying cells by ablation with optical tweezers. Our results support that, in addition to previously discovered mechanisms, cell elimination contributes to regulating lateral root emergence.
Collapse
Affiliation(s)
- Sacha Escamez
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, 901 87 Umeå, Sweden
| | - Domenique André
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, 901 87 Umeå, Sweden
| | - Bernadette Sztojka
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, 901 87 Umeå, Sweden
| | - Benjamin Bollhöner
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, 901 87 Umeå, Sweden
| | - Hardy Hall
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, 901 87 Umeå, Sweden
| | - Béatrice Berthet
- Center for Organismal Studies (COS), University of Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany
| | - Ute Voß
- Centre for Plant Integrative Biology, University of Nottingham, Nottingham LE12 SRD, UK
| | - Amnon Lers
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, Volcani Center, Rishon LeZion, 7528809, Israel
| | - Alexis Maizel
- Center for Organismal Studies (COS), University of Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany
| | | | - Malcolm Bennett
- Centre for Plant Integrative Biology, University of Nottingham, Nottingham LE12 SRD, UK
| | - Hannele Tuominen
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, 901 87 Umeå, Sweden.
| |
Collapse
|
14
|
Ingram GC. Family plot: the impact of the endosperm and other extra-embryonic seed tissues on angiosperm zygotic embryogenesis. F1000Res 2020; 9. [PMID: 32055398 PMCID: PMC6961419 DOI: 10.12688/f1000research.21527.1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/10/2020] [Indexed: 12/22/2022] Open
Abstract
The zygotic embryos of angiosperms develop buried deep within seeds and surrounded by two main extra-embryonic tissues: the maternally derived seed coat tissues and the zygotic endosperm. Generally, these tissues are considered to play an important role in nurturing the developing embryo by acting as conduits for maternally derived nutrients. They are also critical for key seed traits (dormancy establishment and control, longevity, and physical resistance) and thus for seed and seedling survival. However, recent studies have highlighted the fact that extra-embryonic tissues in the seed also physically and metabolically limit embryonic development and that unique mechanisms may have evolved to overcome specific developmental and genetic constraints associated with the seed habit in angiosperms. The aim of this review is to illustrate how these studies have begun to reveal the highly complex physical and physiological relationship between extra-embryonic tissues and the developing embryo. Where possible I focus on Arabidopsis because of space constraints, but other systems will be cited where relevant.
Collapse
Affiliation(s)
- Gwyneth C Ingram
- Laboratoire Reproduction et Développement des Plantes, University of Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, Lyon, France
| |
Collapse
|
15
|
Landrein B, Ingram G. Connected through the force: mechanical signals in plant development. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:3507-3519. [PMID: 30821332 DOI: 10.1093/jxb/erz103] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 02/12/2019] [Indexed: 05/12/2023]
Abstract
As multicellular organisms, plants acquire characteristic shapes through a complex set of biological processes known as morphogenesis. Biochemical signalling underlies much of development, as it allows cells to acquire specific identities based on their position within tissues and organs. However, as growing physical structures, plants, and their constituent cells, also experience internal and external physical forces that can be perceived and can influence key processes such as growth, polarity, and gene expression. This process, which adds another layer of control to growth and development, has important implications for plant morphogenesis. This review provides an overview of recent research into the role of mechanical signals in plant development and aims to show how mechanical signalling can be used, in concert with biochemical signals, as a cue allowing cells and tissues to coordinate their behaviour and to add robustness to developmental processes.
Collapse
Affiliation(s)
- Benoit Landrein
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, Ecole Normale Supérieure de Lyon, UCB Lyon 1, CNRS, INRA, Lyon Cedex, France
| | - Gwyneth Ingram
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, Ecole Normale Supérieure de Lyon, UCB Lyon 1, CNRS, INRA, Lyon Cedex, France
| |
Collapse
|
16
|
Cruz-Valderrama JE, Gómez-Maqueo X, Salazar-Iribe A, Zúñiga-Sánchez E, Hernández-Barrera A, Quezada-Rodríguez E, Gamboa-deBuen A. Overview of the Role of Cell Wall DUF642 Proteins in Plant Development. Int J Mol Sci 2019; 20:E3333. [PMID: 31284602 PMCID: PMC6651502 DOI: 10.3390/ijms20133333] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/02/2019] [Accepted: 07/04/2019] [Indexed: 02/06/2023] Open
Abstract
The DUF642 protein family is found exclusively in spermatophytes and is represented by 10 genes in Arabidopsis and in most of the 24 plant species analyzed to date. Even though the primary structure of DUF642 proteins is highly conserved in different spermatophyte species, studies of their expression patterns in Arabidopsis have shown that the spatial-temporal expression pattern for each gene is specific and consistent with the phenotypes of the mutant plants studied so far. Additionally, the regulation of DUF642 gene expression by hormones and environmental stimuli was specific for each gene, showing both up- and down-regulation depending of the analyzed tissue and the intensity or duration of the stimuli. These expression patterns suggest that the DUF642 genes are involved throughout the development and growth of plants. In general, changes in the expression patterns of DUF642 genes can be related to changes in pectin methyl esterase activity and/or to changes in the degree of methyl-esterified homogalacturonans during plant development in different cell types. Thus, the regulation of pectin methyl esterases mediated by DUF642 genes could contribute to the regulation of the cell wall properties during plant growth.
Collapse
Affiliation(s)
| | - Ximena Gómez-Maqueo
- Instituto de Ecología, Universidad Nacional Autónoma de México. Mexico City 04510, Mexico
| | - Alexis Salazar-Iribe
- Instituto de Ecología, Universidad Nacional Autónoma de México. Mexico City 04510, Mexico
| | - Esther Zúñiga-Sánchez
- Instituto de Ecología, Universidad Nacional Autónoma de México. Mexico City 04510, Mexico
| | | | - Elsa Quezada-Rodríguez
- Instituto de Ecología, Universidad Nacional Autónoma de México. Mexico City 04510, Mexico
| | | |
Collapse
|
17
|
Buono RA, Hudecek R, Nowack MK. Plant proteases during developmental programmed cell death. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2097-2112. [PMID: 30793182 PMCID: PMC7612330 DOI: 10.1093/jxb/erz072] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 02/12/2019] [Indexed: 05/08/2023]
Abstract
Proteases are among the key regulators of most forms of programmed cell death (PCD) in animals. Many PCD processes have also been associated with protease expression or activation in plants, However, functional evidence for the roles and actual modes of action of plant proteases in PCD remains surprisingly limited. In this review, we provide an update on protease involvement in the context of developmentally regulated plant PCD. To illustrate the diversity of protease functions, we focus on several prominent developmental PCD processes, including xylem and tapetum maturation, suspensor elimination, endosperm degradation, and seed coat formation, as well as plant senescence processes. Despite the substantial advances in the field, protease functions are often only correlatively linked to developmental PCD, and the specific molecular roles of proteases in many developmental PCD processes remain to be elucidated.
Collapse
Affiliation(s)
- Rafael Andrade Buono
- Department of Plant Biotechnology and Genetics, Ghent University, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Ghent, Belgium
| | - Roman Hudecek
- Department of Plant Biotechnology and Genetics, Ghent University, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Ghent, Belgium
| | - Moritz K. Nowack
- Department of Plant Biotechnology and Genetics, Ghent University, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Ghent, Belgium
| |
Collapse
|
18
|
MacGregor DR, Zhang N, Iwasaki M, Chen M, Dave A, Lopez‐Molina L, Penfield S. ICE1 and ZOU determine the depth of primary seed dormancy in Arabidopsis independently of their role in endosperm development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 98:277-290. [PMID: 30570804 PMCID: PMC6900779 DOI: 10.1111/tpj.14211] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 11/20/2018] [Accepted: 12/12/2018] [Indexed: 05/06/2023]
Abstract
Seed dormancy is a widespread and key adaptive trait that is essential for the establishment of soil seed banks and prevention of pre-harvest sprouting. Herein we demonstrate that the endosperm-expressed transcription factors ZHOUPI (ZOU) and INDUCER OF CBF EXPRESSION1 (ICE1) play a role in determining the depth of primary dormancy in Arabidopsis. We show that ice1 or zou increases seed dormancy and the double mutant has an additive phenotype. This increased dormancy is associated with increased ABA levels, and can be separated genetically from any role in endosperm maturation because loss of ABA biosynthesis or DELAY OF GERMINATION 1 reverses the dormancy phenotype without affecting the aberrant seed morphology. Consistent with these results, ice1 endosperms had an increased capacity for preventing embryo greening, a phenotype previously associated with an increase in endospermic ABA levels. Although ice1 changes the expression of many genes, including some in ABA biosynthesis, catabolism and/or signalling, only ABA INSENSITIVE 3 is significantly misregulated in ice1 mutants. We also demonstrate that ICE1 binds to and inhibits expression of ABA INSENSITIVE 3. Our data demonstrate that Arabidopsis ICE1 and ZOU determine the depth of primary dormancy during maturation independently of their effect on endosperm development.
Collapse
Affiliation(s)
- Dana R. MacGregor
- Department of Crop GeneticsJohn Innes CentreNorwich Research ParkNorwichNR4 7UHUK
- Present address:
Department of Biointeractions and Crop ProtectionRothamsted ResearchHarpenden, HertfordshireAL5 2JQUK
| | - Naichao Zhang
- Department of Crop GeneticsJohn Innes CentreNorwich Research ParkNorwichNR4 7UHUK
| | - Mayumi Iwasaki
- Department of Plant Biology and Institute for Genetics and Genomics in Geneva (iGE3)University of Geneva30, Quai Ernest‐Ansermet CH‐1211Geneva4Switzerland
| | - Min Chen
- Department of Crop GeneticsJohn Innes CentreNorwich Research ParkNorwichNR4 7UHUK
- Present address:
College of Life Science and TechnologyHuazhong Agricultural UniversityWuhan430070China
| | - Anuja Dave
- Department of Crop GeneticsJohn Innes CentreNorwich Research ParkNorwichNR4 7UHUK
| | - Luis Lopez‐Molina
- Department of Plant Biology and Institute for Genetics and Genomics in Geneva (iGE3)University of Geneva30, Quai Ernest‐Ansermet CH‐1211Geneva4Switzerland
| | - Steven Penfield
- Department of Crop GeneticsJohn Innes CentreNorwich Research ParkNorwichNR4 7UHUK
| |
Collapse
|
19
|
Marsollier AC, Ingram G. Getting physical: invasive growth events during plant development. CURRENT OPINION IN PLANT BIOLOGY 2018; 46:8-17. [PMID: 29981931 DOI: 10.1016/j.pbi.2018.06.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 06/04/2018] [Accepted: 06/07/2018] [Indexed: 05/10/2023]
Abstract
Plant cells are enclosed in cell walls that weld them together, meaning that cells rarely change neighbours. Nonetheless, invasive growth events play critical roles in plant development and are often key hubs for the integration of environmental and/or developmental signalling. Here we review cellular processes involved in three such events: lateral root emergence, pollen tube growth through stigma and style tissues, and embryo expansion through the endosperm (Figures 1-3). We consider processes such as regulation of water fluxes and cell turgor (driving growth), cell wall modifications (e.g. cell separation) and cell death (for creating space) within these three contexts with the aim of identifying key mechanisms implicated in providing a chemical and biophysical environments permitting invasive growth events.
Collapse
Affiliation(s)
- Anne-Charlotte Marsollier
- Université de Lyon, Laboratoire Reproduction et Développement des Plantes, ENS de lyon, CNRS, INRA, 46 Allée d'Italie, 69007 Lyon, France
| | - Gwyneth Ingram
- Université de Lyon, Laboratoire Reproduction et Développement des Plantes, ENS de lyon, CNRS, INRA, 46 Allée d'Italie, 69007 Lyon, France.
| |
Collapse
|
20
|
Cubría-Radío M, Nowack MK. Transcriptional networks orchestrating programmed cell death during plant development. Curr Top Dev Biol 2018; 131:161-184. [PMID: 30612616 PMCID: PMC7116394 DOI: 10.1016/bs.ctdb.2018.10.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
Transcriptional gene regulation is a fundamental biological principle in the development of eukaryotes. It does control not only cell proliferation, specification, and differentiation, but also cell death processes as an integral feature of an organism's developmental program. As in animals, developmentally regulated cell death in plants occurs in numerous contexts and is of vital importance for plant vegetative and reproductive development. In comparison with the information available on the molecular regulation of programmed cell death (PCD) in animals, however, our knowledge on plant PCD still remains scarce. Here, we discuss the functions of different classes of transcription factors that have been implicated in the control of developmentally regulated cell death. Though doubtlessly representing but a first layer of PCD regulation, information on PCD-regulating transcription factors and their targets represents a promising strategy to understand the complex machinery that ensures the precise and failsafe execution of PCD processes in plant development.
Collapse
Affiliation(s)
- Marta Cubría-Radío
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Moritz K Nowack
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; VIB Center for Plant Systems Biology, Ghent, Belgium.
| |
Collapse
|
21
|
Sechet J, Marion-Poll A, North HM. Emerging Functions for Cell Wall Polysaccharides Accumulated during Eudicot Seed Development. PLANTS (BASEL, SWITZERLAND) 2018; 7:E81. [PMID: 30274256 PMCID: PMC6313846 DOI: 10.3390/plants7040081] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/23/2018] [Accepted: 09/27/2018] [Indexed: 01/17/2023]
Abstract
The formation of seeds is a reproductive strategy in higher plants that enables the dispersal of offspring through time and space. Eudicot seeds comprise three main components, the embryo, the endosperm and the seed coat, where the coordinated development of each is important for the correct formation of the mature seed. In addition, the seed coat protects the quiescent progeny and can provide transport mechanisms. A key underlying process in the production of seed tissues is the formation of an extracellular matrix termed the cell wall, which is well known for its essential function in cytokinesis, directional growth and morphogenesis. The cell wall is composed of a macromolecular network of polymers where the major component is polysaccharides. The attributes of polysaccharides differ with their composition and charge, which enables dynamic remodeling of the mechanical and physical properties of the matrix by adjusting their production, modification or turnover. Accordingly, the importance of specific polysaccharides or modifications is increasingly being associated with specialized functions within seed tissues, often through the spatio-temporal accumulation or remodeling of particular polymers. Here, we review the evolution and accumulation of polysaccharides during eudicot seed development, what is known of their impact on wall architecture and the diverse roles associated with these in different seed tissues.
Collapse
Affiliation(s)
- Julien Sechet
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000 Versailles, France.
| | - Annie Marion-Poll
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000 Versailles, France.
| | - Helen M North
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000 Versailles, France.
| |
Collapse
|
22
|
Feng F, Song R. O11 is multi-functional regulator in maize endosperm. PLANT SIGNALING & BEHAVIOR 2018; 13:e1451709. [PMID: 29533128 PMCID: PMC5933909 DOI: 10.1080/15592324.2018.1451709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 03/06/2018] [Indexed: 05/30/2023]
Abstract
As a highly developed tissue, maize endosperm accumulates nutrients abundantly and supports embryo development. In a recent study, we constructed a regulatory network centered around Opaque11 (O11). This network unified cellular development, nutrient metabolism and stress responses during endosperm development. Here we discuss the evidences that O11 might have a regulatory role in cold stress response during seed development. Furthermore, we discuss the functional divergence between maize O11 and its Arabidopsis orthologue ZHOUPI, which might explain some of the differences in endosperm development between monocotyledonous and dicotyledonous seeds.
Collapse
Affiliation(s)
- Fan Feng
- Shanghai Key Laboratory of Bio-Energy Crops, Plant Science Center, School of Life Sciences, Shanghai University, Shanghai, China
| | - Rentao Song
- Shanghai Key Laboratory of Bio-Energy Crops, Plant Science Center, School of Life Sciences, Shanghai University, Shanghai, China
- National Maize Improvement Center of China, China Agricultural University, Beijing, China
| |
Collapse
|
23
|
Steinbrecher T, Leubner-Metzger G. Tissue and cellular mechanics of seeds. Curr Opin Genet Dev 2018; 51:1-10. [PMID: 29571069 DOI: 10.1016/j.gde.2018.03.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 02/27/2018] [Accepted: 03/01/2018] [Indexed: 01/17/2023]
Abstract
Distinct plant seed/fruit structures evolved to support reproduction and dispersal in distinct environments. Appropriate biomechanical properties and interactions of the various seed compartments are indispensable to plant survival. Most seeds are dispersed in a dry state generated during seed development/maturation for which novel aspects of endosperm-embryo interaction were discovered. The various layers covering the embryo of a mature seed define the patterns of water uptake during germination. Their biomechanical weakening together with embryo cell expansion is mediated by cell wall remodelling to facilitate radicle protrusion. Recent work with different species has revealed mechanisms underpinning specific embryo growth zones. Abiotic and biotic factors were shown to release different types of seed and fruit coat-mediated constraints to water uptake and germination.
Collapse
Affiliation(s)
- Tina Steinbrecher
- School of Biological Sciences, Plant Molecular Science and Centre for Systems and Synthetic Biology, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK(1).
| | - Gerhard Leubner-Metzger
- School of Biological Sciences, Plant Molecular Science and Centre for Systems and Synthetic Biology, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK(1).
| |
Collapse
|
24
|
Dou M, Zhang Y, Yang S, Feng X. Identification of ZHOUPI Orthologs in Rice Involved in Endosperm Development and Cuticle Formation. FRONTIERS IN PLANT SCIENCE 2018. [PMID: 29541083 PMCID: PMC5835929 DOI: 10.3389/fpls.2018.00223] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The endosperm occupies most of the available space within mature rice seeds, contains abundant nutrients, and directly influences both the quality and quantity of rice production. Initial reports noted that AtZHOUPI (AtZOU) coordinates endosperm breakdown and the concomitant separation of the embryo from this structure in Arabidopsis. The results of this study show that rice genomes contain two most closely related homologs of AtZOU, OsZOU-1 and OsZOU-2; of these, OsZOU-1 expression is limited to within the endosperm where it can be detected throughout this structure 5 days after pollination (DAP). Its expression gradually decreases from seven DAP to nine DAP. The second of the two most closely related homologs, OsZOU-2, is highly expressed in leaves and stem, but is not detected in developing seeds. Heterologous expression of OsZOU-1 and OsZOU-2 in Atzou-4 mutants also revealed that OsZOU-1 partially complements the seed phenotypes of these individuals, while its counterpart, OsZOU-2, was unable to recover these phenotypes. The over-expression of OsZOU-1 severely disrupts both seed development and plant growth in transgenic rice lines, as plants in which this gene has been knocked down failed in the separation of endosperm from embryo and cuticle formation during seed development. The results of this study therefore suggest that OsZOU-1 is orthologous to the AtZOU, and regulates both endosperm development and cuticle formation in rice.
Collapse
Affiliation(s)
- Mingzhu Dou
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology (CAS), Changchun, China
- College of Life Sciences, Liaocheng University, Liaocheng, China
| | - Yaohua Zhang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology (CAS), Changchun, China
| | - Suxin Yang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology (CAS), Changchun, China
- *Correspondence: Suxin Yang, Xianzhong Feng,
| | - Xianzhong Feng
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology (CAS), Changchun, China
- *Correspondence: Suxin Yang, Xianzhong Feng,
| |
Collapse
|
25
|
Inácio V, Martins MT, Graça J, Morais-Cecílio L. Cork Oak Young and Traumatic Periderms Show PCD Typical Chromatin Patterns but Different Chromatin-Modifying Genes Expression. FRONTIERS IN PLANT SCIENCE 2018; 9:1194. [PMID: 30210513 PMCID: PMC6120546 DOI: 10.3389/fpls.2018.01194] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 07/25/2018] [Indexed: 05/20/2023]
Abstract
Plants are subjected to adverse conditions being outer protective tissues fundamental to their survival. Tree stems are enveloped by a periderm made of cork cells, resulting from the activity of the meristem phellogen. DNA methylation and histone modifications have important roles in the regulation of plant cell differentiation. However, studies on its involvement in cork differentiation are scarce despite periderm importance. Cork oak periderm development was used as a model to study the formation and differentiation of secondary protective tissues, and their behavior after traumatic wounding (traumatic periderm). Nuclei structural changes, dynamics of DNA methylation, and posttranslational histone modifications were assessed in young and traumatic periderms, after cork harvesting. Lenticular phellogen producing atypical non-suberized cells that disaggregate and form pores was also studied, due to high impact for cork industrial uses. Immunolocalization of active and repressive marks, transcription analysis of the corresponding genes, and correlations between gene expression and cork porosity were investigated. During young periderm development, a reduction in nuclei area along with high levels of DNA methylation occurred throughout epidermis disruption. As cork cells became more differentiated, whole nuclei progressive chromatin condensation with accumulation in the nuclear periphery and increasing DNA methylation was observed. Lenticular cells nuclei were highly fragmented with faint 5-mC labeling. Phellogen nuclei were less methylated than in cork cells, and in lenticular phellogen were even lower. No significant differences were detected in H3K4me3 and H3K18ac signals between cork cells layers, although an increase in H3K4me3 signals was found from the phellogen to cork cells. Distinct gene expression patterns in young and traumatic periderms suggest that cork differentiation might be under specific silencing regulatory pathways. Significant correlations were found between QsMET1, QsMET2, and QsSUVH4 gene expression and cork porosity. This work evidences that DNA methylation and histone modifications play a role in cork differentiation and epidermis induced tension-stress. It also provides the first insights into chromatin dynamics during cork and lenticular cells differentiation pointing to a distinct type of remodeling associated with cell death.
Collapse
Affiliation(s)
- Vera Inácio
- Linking Landscape, Environment, Agriculture and Food (LEAF), Institute of Agronomy, University of Lisbon, Lisbon, Portugal
- *Correspondence: Vera Inácio,
| | - Madalena T. Martins
- Linking Landscape, Environment, Agriculture and Food (LEAF), Institute of Agronomy, University of Lisbon, Lisbon, Portugal
| | - José Graça
- Forest Research Center (CEF), Institute of Agronomy, University of Lisbon, Lisbon, Portugal
| | - Leonor Morais-Cecílio
- Linking Landscape, Environment, Agriculture and Food (LEAF), Institute of Agronomy, University of Lisbon, Lisbon, Portugal
| |
Collapse
|
26
|
Cruz-Valderrama JE, Jiménez-Durán K, Zúñiga-Sánchez E, Salazar-Iribe A, Márquez-Guzmán J, Gamboa-deBuen A. Degree of pectin methyl esterification in endosperm cell walls is involved in embryo bending in Arabidopsis thaliana. Biochem Biophys Res Commun 2017; 495:639-645. [PMID: 29137987 DOI: 10.1016/j.bbrc.2017.11.077] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 11/10/2017] [Indexed: 01/24/2023]
Abstract
The endosperm is a transitory structure involved in proper embryo elongation. The cell walls of mature seed endosperm are generally composed of a uniform distribution of cellulose, unesterified homogalacturonans, and arabinans. Recent studies suggest that changes in cell wall properties during endosperm development could be related to embryo growth. The degree of methyl esterification of homogalacturonans may be involved in this endosperm tissue remodelling. The relevance of the degree of homogalacturonan methyl esterification during seed development was determined by immunohistochemical analyses using a panel of probes with specificity for homogalaturonans with different degrees of methyl esterification. Low-esterified and un-esterified homogalacturonans were abundant in endosperm cells during embryo bending and were also detected in mature embryos. BIDXII (BDX) could be involved in seed development, because bdx-1 mutants had misshapen embryos. The methyl esterification pattern described for WT seeds was different during bdx-1 seed development; un-esterified homogalacturonans were scarcely present in the cell walls of endosperm in bending embryos and mature seeds. Our results suggested that the degree of methyl esterification of homogalacturonans in the endosperm cell wall may be involved in proper embryo development.
Collapse
Affiliation(s)
- José E Cruz-Valderrama
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad Universitaria, CP.04510, CDMX, Mexico
| | - Karina Jiménez-Durán
- Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, CP.04510, CDMX, Mexico
| | - Esther Zúñiga-Sánchez
- Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, CP.04510, CDMX, Mexico
| | - Alexis Salazar-Iribe
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad Universitaria, CP.04510, CDMX, Mexico
| | - Judith Márquez-Guzmán
- Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria, CP.04510, CDMX, Mexico
| | - Alicia Gamboa-deBuen
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad Universitaria, CP.04510, CDMX, Mexico.
| |
Collapse
|
27
|
Ingram G, Nawrath C. The roles of the cuticle in plant development: organ adhesions and beyond. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:5307-5321. [PMID: 28992283 DOI: 10.1093/jxb/erx313] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Cuticles, which are composed of a variety of aliphatic molecules, impregnate epidermal cell walls forming diffusion barriers that cover almost all the aerial surfaces in higher plants. In addition to revealing important roles for cuticles in protecting plants against water loss and other environmental stresses and aggressions, mutants with permeable cuticles show major defects in plant development, such as abnormal organ formation as well as altered seed germination and viability. However, understanding the mechanistic basis for these developmental defects represents a significant challenge due to the pleiotropic nature of phenotypes and the altered physiological status/viability of some mutant backgrounds. Here we discuss both the basis of developmental phenotypes associated with defects in cuticle function and mechanisms underlying developmental processes that implicate cuticle modification. Developmental abnormalities in cuticle mutants originate at early developmental time points, when cuticle composition and properties are very difficult to measure. Nonetheless, we aim to extract principles from existing data in order to pinpoint the key cuticle components and properties required for normal plant development. Based on our analysis, we will highlight several major questions that need to be addressed and technical hurdles that need to be overcome in order to advance our current understanding of the developmental importance of plant cuticles.
Collapse
Affiliation(s)
- Gwyneth Ingram
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, CNRS, INRA, UCB Lyon 1, Ecole Normale Supérieure de Lyon, F-69342 Lyon, France
| | - Christiane Nawrath
- University of Lausanne, Department of Plant Molecular Biology, Biophore Building, CH-1015 Lausanne, Switzerland
| |
Collapse
|
28
|
Niu X, Guan Y, Chen S, Li H. Genome-wide analysis of basic helix-loop-helix (bHLH) transcription factors in Brachypodium distachyon. BMC Genomics 2017; 18:619. [PMID: 28810832 PMCID: PMC5558667 DOI: 10.1186/s12864-017-4044-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 08/09/2017] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND As a superfamily of transcription factors (TFs), the basic helix-loop-helix (bHLH) proteins have been characterized functionally in many plants with a vital role in the regulation of diverse biological processes including growth, development, response to various stresses, and so on. However, no systemic analysis of the bHLH TFs has been reported in Brachypodium distachyon, an emerging model plant in Poaceae. RESULTS A total of 146 bHLH TFs were identified in the Brachypodium distachyon genome and classified into 24 subfamilies. BdbHLHs in the same subfamily share similar protein motifs and gene structures. Gene duplication events showed a close relationship to rice, maize and sorghum, and segment duplications might play a key role in the expansion of this gene family. The amino acid sequence of the bHLH domains were quite conservative, especially Leu-27 and Leu-54. Based on the predicted binding activities, the BdbHLHs were divided into DNA binding and non-DNA binding types. According to the gene ontology (GO) analysis, BdbHLHs were speculated to function in homodimer or heterodimer manner. By integrating the available high throughput data in public database and results of quantitative RT-PCR, we found the expression profiles of BdbHLHs were different, implying their differentiated functions. CONCLUSION One hundred fourty-six BdbHLHs were identified and their conserved domains, sequence features, phylogenetic relationship, chromosomal distribution, GO annotations, gene structures, gene duplication and expression profiles were investigated. Our findings lay a foundation for further evolutionary and functional elucidation of BdbHLH genes.
Collapse
Affiliation(s)
- Xin Niu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, China
| | - Yuxiang Guan
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, China
| | - Shoukun Chen
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, China
| | - Haifeng Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, China
- Xinjiang Agricultural Vocational Technical College, Changji, China
| |
Collapse
|
29
|
Escamez S, Tuominen H. Contribution of cellular autolysis to tissular functions during plant development. CURRENT OPINION IN PLANT BIOLOGY 2017; 35:124-130. [PMID: 27936412 DOI: 10.1016/j.pbi.2016.11.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 11/23/2016] [Accepted: 11/25/2016] [Indexed: 05/26/2023]
Abstract
Plant development requires specific cells to be eliminated in a predictable and genetically regulated manner referred to as programmed cell death (PCD). However, the target cells do not merely die but they also undergo autolysis to degrade their cellular corpses. Recent progress in understanding developmental cell elimination suggests that distinct proteins execute PCD sensu stricto and autolysis. In addition, cell death alone and cell dismantlement can fulfill different functions. Hence, it appears biologically meaningful to distinguish between the modules of PCD and autolysis during plant development.
Collapse
Affiliation(s)
- Sacha Escamez
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, SE-90187 Umeå, Sweden
| | - Hannele Tuominen
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, SE-90187 Umeå, Sweden.
| |
Collapse
|
30
|
Affiliation(s)
- Steven Penfield
- Department of Crop Genetics, John Innes Centre, Norwich Research Park, Norwick, NR4 7UH, UK
| |
Collapse
|
31
|
Steinbrecher T, Leubner-Metzger G. The biomechanics of seed germination. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:765-783. [PMID: 27927995 DOI: 10.1093/jxb/erw428] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
From a biomechanical perspective, the completion of seed (and fruit) germination depends on the balance of two opposing forces: the growth potential of the embryonic axis (radicle-hypocotyl growth zone) and the restraint of the seed-covering layers (endosperm, testa, and pericarp). The diverse seed tissues are composite materials which differ in their dynamic properties based on their distinct cell wall composition and water uptake capacities. The biomechanics of embryo cell growth during seed germination depend on irreversible cell wall loosening followed by water uptake due to the decreasing turgor, and this leads to embryo elongation and eventually radicle emergence. Endosperm weakening as a prerequisite for radicle emergence is a widespread phenomenon among angiosperms. Research into the biochemistry and biomechanics of endosperm weakening has demonstrated that the reduction in puncture force of a seed's micropylar endosperm is environmentally and hormonally regulated and involves tissue-specific expression of cell wall remodelling proteins such as expansins, diverse hydrolases, and the production of directly acting apoplastic reactive oxygen. The endosperm-weakening biomechanics and its underlying cell wall biochemistry differ between the micropylar (ME) and chalazal (CE) endosperm domains. In the ME, they involve cell wall loosening, cell separation, and programmed cell death to provide decreased and localized ME tissue resistance, autolysis, and finally the formation of an ME hole required for radicle emergence. Future work will further unravel the molecular mechanisms, environmental regulation, and evolution of the diverse biomechanical cell wall changes underpinning the control of germination by endosperm weakening.
Collapse
Affiliation(s)
- Tina Steinbrecher
- School of Biological Sciences, Plant Molecular Science and Centre for Systems and Synthetic Biology, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Gerhard Leubner-Metzger
- School of Biological Sciences, Plant Molecular Science and Centre for Systems and Synthetic Biology, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| |
Collapse
|
32
|
Huysmans M, Lema A S, Coll NS, Nowack MK. Dying two deaths - programmed cell death regulation in development and disease. CURRENT OPINION IN PLANT BIOLOGY 2017; 35:37-44. [PMID: 27865098 DOI: 10.1016/j.pbi.2016.11.005] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/28/2016] [Accepted: 11/03/2016] [Indexed: 05/18/2023]
Abstract
Programmed cell death (PCD) is a fundamental cellular process that has adopted a plethora of vital functions in multicellular organisms. In plants, PCD processes are elicited as an inherent part of regular development in specific cell types or tissues, but can also be triggered by biotic and abiotic stresses. Although over the last years we have seen progress in our understanding of the molecular regulation of different plant PCD processes, it is still unclear whether a common core machinery exists that controls cell death in development and disease. In this review, we discuss recent advances in the field, comparing some aspects of the molecular regulation controlling developmental and pathogen-triggered PCD in plants.
Collapse
Affiliation(s)
- Marlies Huysmans
- VIB Department of Plant Systems Biology, 9052 Gent, Belgium; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
| | - Saul Lema A
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra-Cerdanyola del Valles 08193, Catalonia, Spain
| | - Nuria S Coll
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra-Cerdanyola del Valles 08193, Catalonia, Spain.
| | - Moritz K Nowack
- VIB Department of Plant Systems Biology, 9052 Gent, Belgium; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium.
| |
Collapse
|
33
|
Ingram GC. Dying to live: cell elimination as a developmental strategy in angiosperm seeds. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:785-796. [PMID: 27702990 DOI: 10.1093/jxb/erw364] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The complete elimination of unwanted cells during development is a repeated theme in both multicellular animals and in plants. In plants, such events have been extensively studied and reviewed in terms of their molecular regulation, of marker genes and proteins expressed, and in terms of cellular changes associated with their progression. This review will take a slightly different view of developmental cell elimination and will concentrate specifically on the numerous elimination events that occur during ovule and seed development (here grouped together as seed development). It asks why this cell elimination occurs in specific seed tissues, in order to understand something about the commonalities underlying how seemingly disparate events are triggered and regulated. Finally, by placing the seed in its broader evolutionary context, the question of why cell elimination may have emerged as such a key component of the seed developmental toolbox will be considered.
Collapse
Affiliation(s)
- Gwyneth C Ingram
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, CNRS (UMR 5667), INRA (UMR 0879), UCB Lyon 1, Ecole Normale Supérieure de Lyon, F-69342 Lyon, France
| |
Collapse
|
34
|
Galsurker O, Doron-Faigenboim A, Teper-Bamnolker P, Daus A, Fridman Y, Lers A, Eshel D. Cellular and Molecular Changes Associated with Onion Skin Formation Suggest Involvement of Programmed Cell Death. FRONTIERS IN PLANT SCIENCE 2016; 7:2031. [PMID: 28119713 PMCID: PMC5220068 DOI: 10.3389/fpls.2016.02031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 12/19/2016] [Indexed: 05/07/2023]
Abstract
Skin formation of onion (Allium cepa L.) bulb involves scale desiccation accompanied by scale senescence, resulting in cell death and tissue browning. Understanding the mechanism of skin formation is essential to improving onion skin and bulb qualities. Although onion skin plays a crucial role in postharvest onion storage and shelf life, its formation is poorly understood. We investigated the mode of cell death in the outermost scales that are destined to form the onion skin. Surprisingly, fluorescein diacetate staining and scanning electron microscopy indicated that the outer scale desiccates from the inside out. This striking observation suggests that cell death in the outer scales, during skin formation, is an internal and organized process that does not derive only from air desiccation. DNA fragmentation, a known hallmark of programmed cell death (PCD), was revealed in the outer scales and gradually decreased toward the inner scales of the bulb. Transmission electron microscopy further revealed PCD-related structural alterations in the outer scales which were absent from the inner scales. De novo transcriptome assembly for three different scales: 1st (outer), 5th (intermediate) and 8th (inner) fleshy scales identified 2,542 differentially expressed genes among them. GO enrichment for cluster analysis revealed increasing metabolic processes in the outer senescent scale related to defense response, PCD processes, carbohydrate metabolism and flavonoid biosynthesis, whereas increased metabolism and developmental growth processes were identified in the inner scales. High expression levels of PCD-related genes were identified in the outer scale compared to the inner ones, highlighting the involvement of PCD in outer-skin development. These findings suggest that a program to form the dry protective skin exists and functions only in the outer scales of onion.
Collapse
Affiliation(s)
- Ortal Galsurker
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
- The Robert H. Smith Institute of Field Crops and Vegetables, Robert H. Smith Faculty of Agriculture Food and Environment, The Hebrew University of JerusalemRehovot, Israel
| | - Adi Doron-Faigenboim
- Institute of Plant Sciences, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
| | - Paula Teper-Bamnolker
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
| | - Avinoam Daus
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
| | - Yael Fridman
- The Alexander Silberman Institute of Life Science, Edmond Safra Campus (G Ram), The Hebrew UniversityJerusalem, Israel
| | - Amnon Lers
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
| | - Dani Eshel
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
- *Correspondence: Dani Eshel,
| |
Collapse
|