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Ogawa ST, Kessler SA. Update on signaling pathways regulating polarized intercellular communication in Arabidopsis reproduction. PLANT PHYSIOLOGY 2023; 193:1732-1744. [PMID: 37453128 DOI: 10.1093/plphys/kiad414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 06/22/2023] [Accepted: 06/22/2023] [Indexed: 07/18/2023]
Affiliation(s)
- Sienna T Ogawa
- Department of Botany and Plant Pathology and Center for Plant Biology, Purdue University, West Lafayette, IN 47905, USA
| | - Sharon A Kessler
- Department of Botany and Plant Pathology and Center for Plant Biology, Purdue University, West Lafayette, IN 47905, USA
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2
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Salehi H, Chehregani Rad A, Sharifan H, Raza A, Varshney RK. Aerially Applied Zinc Oxide Nanoparticle Affects Reproductive Components and Seed Quality in Fully Grown Bean Plants ( Phaseolus vulgaris L.). FRONTIERS IN PLANT SCIENCE 2022; 12:808141. [PMID: 35095979 PMCID: PMC8790032 DOI: 10.3389/fpls.2021.808141] [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: 11/03/2021] [Accepted: 12/02/2021] [Indexed: 06/14/2023]
Abstract
The development of reproductive components in plant species is susceptible to environmental stresses. The extensive application of zinc oxide nanoparticles (nZnO) in various agro-industrial processes has jeopardized the performance and functionality of plants. To understand the response of the developmental (gametogenesis and sporogenesis) processes to nanoparticles (NPs) exposure, the aerial application of nZnO and their ionic counterpart of ZnSO4 at four different levels were examined on bean plants (Phaseolus vulgaris) before the flowering stage. To evaluate the mentioned processes, briefly, flowers in multiple sizes were fixed in paraffin, followed by sectioning and optical analysis. The possibility of alteration in reproductive cells was thoroughly analyzed using both light and electron microscopes. Overall, our results revealed the histological defects in male and female reproductive systems of mature plants depend on NPs levels. Furthermore, NPs caused tapetum abnormalities, aberrations in carbohydrate accumulation, and apoptosis. The nZnO induced abnormal alterations right after meiosis and partly hindered the microspore development, leading to infertile pollens. The seed yield and dry weight were reduced to 70 and 82% at 2,000 mg L-1 nZnO foliar exposure, respectively. The sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis pattern showed the increased expression of two proteins at the molecular weight of 28 and 42 kDa at various concentrations of nZnO and ZnSO4. Overall, our results provided novel insights into the negative effect of nano-scaled Zn on the differential mechanism involved in the reproductive stage of the plants compared with salt form.
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Affiliation(s)
- Hajar Salehi
- Laboratory of Plant Cell Biology, Department of Biology, Bu-Ali Sina University, Hamedan, Iran
| | | | - Hamidreza Sharifan
- Department of Natural Science, Albany State University, Albany, GA, United States
| | - Ali Raza
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Oil Crops Research Institute, Center of Legume Crop Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Rajeev K. Varshney
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Oil Crops Research Institute, Center of Legume Crop Genetics and Systems Biology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China
- Center of Excellence in Genomics and Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, India
- State Agricultural Biotechnology Centre, Centre for Crop and Food Innovation, Murdoch University, Murdoch, WA, Australia
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3
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Ju Y, Yuan J, Jones DS, Zhang W, Staiger CJ, Kessler SA. Polarized NORTIA accumulation in response to pollen tube arrival at synergids promotes fertilization. Dev Cell 2021; 56:2938-2951.e6. [PMID: 34672969 DOI: 10.1016/j.devcel.2021.09.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 07/28/2021] [Accepted: 09/28/2021] [Indexed: 11/30/2022]
Abstract
Signal-mediated regulation of protein trafficking is an elegant mechanism for controlling the delivery of molecules to a precise location for critical signaling events that occur over short time frames. During plant reproduction, the FERONIA receptor complex is critical for intercellular communication that leads to gamete delivery; however, the impact of the FERONIA signal transduction cascade on protein trafficking in synergid cells remains unknown. Live imaging of pollen tube reception has revealed that a key outcome of FERONIA signaling is polar accumulation of the MLO protein NORTIA at the filiform apparatus in response to signals from an arriving pollen tube. Artificial delivery of NORTIA to the filiform apparatus is sufficient to bypass the FERONIA signaling pathway and to promote interspecific pollen tube reception. We propose that polar accumulation of NORTIA leads to the production of a secondary booster signal to ensure that pollen tubes burst to deliver the sperm cells for double fertilization.
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Affiliation(s)
- Yan Ju
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Jing Yuan
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Daniel S Jones
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK 73019, USA
| | - Weiwei Zhang
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA; Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Christopher J Staiger
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA; Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Sharon A Kessler
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA; Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA.
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4
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Kim MJ, Jeon BW, Oh E, Seo PJ, Kim J. Peptide Signaling during Plant Reproduction. TRENDS IN PLANT SCIENCE 2021; 26:822-835. [PMID: 33715959 DOI: 10.1016/j.tplants.2021.02.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 02/02/2021] [Accepted: 02/17/2021] [Indexed: 05/08/2023]
Abstract
Plant signaling peptides are involved in cell-cell communication networks and coordinate a wide range of plant growth and developmental processes. Signaling peptides generally bind to receptor-like kinases, inducing their dimerization with co-receptors for signaling activation to trigger cellular signaling and biological responses. Fertilization is an important life event in flowering plants, involving precise control of cell-cell communications between male and female tissues. Peptide-receptor-like kinase-mediated signaling plays an important role in male-female interactions for successful fertilization in flowering plants. Here, we describe the recent findings on the functions and signaling pathways of peptides and receptors involved in plant reproduction processes including pollen germination, pollen tube growth, pollen tube guidance to the embryo sac, and sperm cell reception in female tissues.
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Affiliation(s)
- Min-Jung Kim
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea; Department of Integrative Food, Bioscience, and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Byeong Wook Jeon
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea; Department of Integrative Food, Bioscience, and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Eunkyoo Oh
- Department of Life Sciences, Korea University, Seoul 02841, Korea
| | - Pil Joon Seo
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Jungmook Kim
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea; Department of Integrative Food, Bioscience, and Technology, Chonnam National University, Gwangju 61186, Korea; Kumho Life Science Laboratory, Chonnam National University, Buk-Gu, Gwangju 61186, Korea.
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5
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Ambastha V, Leshem Y. Cyclin B1;1 activity is observed in lateral roots but not in the primary root during lethal salinity and salt stress recovery. PLANT SIGNALING & BEHAVIOR 2020; 15:1776026. [PMID: 32564656 PMCID: PMC8570749 DOI: 10.1080/15592324.2020.1776026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/25/2020] [Accepted: 05/26/2020] [Indexed: 06/07/2023]
Abstract
Earlier, we reported that Arabidopsis young lateral roots (LR) exhibited improved lethal salinity tolerance as compared with the primary root (PR). We have shown that cell death processes which take place in the PR during salt stress are postponed in the LR. Still, very little is known about the regulation of cell survival mechanisms in the LR during salinity stress. Here we used transgenic Arabidopsis plants expressing Cyclin B1;1:GUS, to further study the responses to salinity in the PR and LR positions. We found strong Cyclin B1;1:GUS activity in young budding LR of salt stressed and stress recovered plants. The Cyclin B1;1:GUS activity dropped significantly in long LR and was almost completely abolished in the PR. Our data provides another line of evidence that position-dependent response occurs in Arabidopsis roots during lethal salinity. The possible roles Cyclin B1;1 plays in the young LR during the response to lethal salinity are discussed.
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Affiliation(s)
- Vivek Ambastha
- Department of Plant Sciences, MIGAL - Galilee Research Institute, Kiryat-Shmona, Israel
| | - Yehoram Leshem
- Department of Plant Sciences, MIGAL - Galilee Research Institute, Kiryat-Shmona, Israel
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6
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Hater F, Nakel T, Groß-Hardt R. Reproductive Multitasking: The Female Gametophyte. ANNUAL REVIEW OF PLANT BIOLOGY 2020; 71:517-546. [PMID: 32442389 DOI: 10.1146/annurev-arplant-081519-035943] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Fertilization of flowering plants requires the organization of complex tasks, many of which become integrated by the female gametophyte (FG). The FG is a few-celled haploid structure that orchestrates division of labor to coordinate successful interaction with the sperm cells and their transport vehicle, the pollen tube. As reproductive outcome is directly coupled to evolutionary success, the underlying mechanisms are under robust molecular control, including integrity check and repair mechanisms. Here, we review progress on understanding the development and function of the FG, starting with the functional megaspore, which represents the haploid founder cell of the FG. We highlight recent achievements that have greatly advanced our understanding of pollen tube attraction strategies and the mechanisms that regulate plant hybridization and gamete fusion. In addition, we discuss novel insights into plant polyploidization strategies that expand current concepts on the evolution of flowering plants.
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Affiliation(s)
- Friederike Hater
- Centre for Biomolecular Interactions, University of Bremen, 28359 Bremen, Germany;
| | - Thomas Nakel
- Centre for Biomolecular Interactions, University of Bremen, 28359 Bremen, Germany;
| | - Rita Groß-Hardt
- Centre for Biomolecular Interactions, University of Bremen, 28359 Bremen, Germany;
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7
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Losada JM, Herrero M. Arabinogalactan proteins mediate intercellular crosstalk in the ovule of apple flowers. PLANT REPRODUCTION 2019; 32:291-305. [PMID: 31049682 DOI: 10.1007/s00497-019-00370-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 04/23/2019] [Indexed: 05/29/2023]
Abstract
AGP-rich glycoproteins mediate pollen-ovule interactions and cell patterning in the embryo sac of apple before and after fertilization. Glycoproteins are significant players in the dialog that takes place between growing pollen tubes and the stigma and style in the angiosperms. Yet, information is scarce on their possible involvement in the ovule, a sporophytic organ that hosts the female gametophyte. Apple flowers have a prolonged lapse of time between pollination and fertilization, offering a great system to study the developmental basis of glycoprotein secretion and their putative role during the last stages of the progamic phase and early seed initiation. For this purpose, the sequential pollen tube elongation within the ovary was examined in relation to changes in arabinogalactan proteins (AGPs) in the tissues of the ovule before and after fertilization. To evaluate what of these changes are developmentally regulated, unpollinated and pollinated flowers were compared. AGPs paved the pollen tube pathway in the ovules along the micropylar canal, and the nucellus entrance toward the synergids, which also developmentally accumulated AGPs at the filiform apparatus. Glycoproteins vanished from all these tissues following pollen tube passage, strongly suggesting a role in pollen-ovule interaction. In addition, AGPs marked the primary cell walls of the haploid cells of the female gametophyte, and they further built up in the cell walls of the embryo sac and developing embryo, layering the interactive walls of the three generations hosted in the ovule, the maternal sporophytic tissues, the female gametophyte, and the developing embryo.
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Affiliation(s)
- Juan M Losada
- Pomology Department, Aula Dei Experimental Station-CSIC, Avda Montañana 1005, 50059, Saragossa, Spain.
- Arnold Arboretum of Harvard University, 1300 Centre St., Boston, MA, 02131, USA.
- Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora-CSIC-UMA, Avda. Dr. Wienberg s/n. Algarrobo-Costa, 29750, Málaga, Spain.
| | - María Herrero
- Pomology Department, Aula Dei Experimental Station-CSIC, Avda Montañana 1005, 50059, Saragossa, Spain
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8
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Lopes AL, Moreira D, Ferreira MJ, Pereira AM, Coimbra S. Insights into secrets along the pollen tube pathway in need to be discovered. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2979-2992. [PMID: 30820535 DOI: 10.1093/jxb/erz087] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 02/08/2019] [Indexed: 06/09/2023]
Abstract
The process of plant fertilization provides an outstanding example of refined control of gene expression. During this elegant process, subtle communication occurs between neighboring cells, based on chemical signals, that induces cellular mechanisms of patterning and growth. Having faced an immediate issue of self-incompatibility responses, the pathway to fertilization starts once the stigmatic cells recognize a compatible pollen grain, and it continues with numerous players interacting to affect pollen tube growth and the puzzling process of navigation along the transmitting tract. The pollen tube goes through a guidance process that begins with a preovular stage (i.e. prior to the influence of the target ovule), with interactions with factors from the transmitting tissue. In the subsequent ovular-guidance stage a specific relationship develops between the pollen tube and its target ovule. This stage is divided into the funicular and micropylar guidance steps, with numerous receptors working in signalling cascades. Finally, just after the pollen tube has passed beyond the synergids, fusion of the gametes occurs and the developing seed-the ultimate aim of the process-will start to mature. In this paper, we review the existing knowledge of the crucial biological processes involved in pollen-pistil interactions that give rise to the new seed.
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Affiliation(s)
- Ana Lúcia Lopes
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
- Biosystems and Integrative Sciences Institute - BioISI, Porto, Portugal
- Sustainable Agrifood Production Research Centre - GreenUPorto, Vairão, Portugal
| | - Diana Moreira
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
| | - Maria João Ferreira
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
| | - Ana Marta Pereira
- Dipartimento di Bioscienze, Università Degli Studi di Milano, Milano, Italy
| | - Sílvia Coimbra
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
- Sustainable Agrifood Production Research Centre - GreenUPorto, Vairão, Portugal
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9
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Jones DS, Liu X, Willoughby AC, Smith BE, Palanivelu R, Kessler SA. Cellular distribution of secretory pathway markers in the haploid synergid cells of Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 94:192-202. [PMID: 29385641 DOI: 10.1111/tpj.13848] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 12/21/2017] [Accepted: 01/17/2018] [Indexed: 06/07/2023]
Abstract
In flowering plants, cell-cell communication plays a key role in reproductive success, as both pollination and fertilization require pathways that regulate interactions between many different cell types. Some of the most critical of these interactions are those between the pollen tube (PT) and the embryo sac, which ensure the delivery of sperm cells required for double fertilization. Synergid cells function to attract the PT through secretion of small peptides and in PT reception via membrane-bound proteins associated with the endomembrane system and the cell surface. While many synergid-expressed components regulating PT attraction and reception have been identified, few tools exist to study the localization of membrane-bound proteins and the components of the endomembrane system in this cell type. In this study, we describe the localization and distribution of seven fluorescent markers that labelled components of the secretory pathway in synergid cells of Arabidopsis thaliana. These markers were used in co-localization experiments to investigate the subcellular distribution of the two PT reception components LORELEI, a GPI-anchored surface protein, and NORTIA, a MILDEW RESISTANCE LOCUS O protein, both found within the endomembrane system of the synergid cell. These secretory markers are useful tools for both reproductive and cell biologists, enabling the analysis of membrane-associated trafficking within a haploid cell actively involved in polar transport.
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Affiliation(s)
- Daniel S Jones
- Department of Microbiology and Plant Biology, The University of Oklahoma, Norman, OK, 73069, USA
| | - Xunliang Liu
- School of Plant Sciences, University of Arizona, Tucson, Arizona, 85721, USA
| | - Andrew C Willoughby
- Department of Microbiology and Plant Biology, The University of Oklahoma, Norman, OK, 73069, USA
| | - Benjamin E Smith
- Vision Sciences, University of California, Berkeley, CA, 94720, USA
| | | | - Sharon A Kessler
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
- Center for Plant Biology, Purdue University, West Lafayette, IN, 47907, USA
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10
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Kanaoka MM. Cell-cell communications and molecular mechanisms in plant sexual reproduction. JOURNAL OF PLANT RESEARCH 2018; 131:37-47. [PMID: 29181649 DOI: 10.1007/s10265-017-0997-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 10/29/2017] [Indexed: 06/07/2023]
Abstract
Sexual reproduction is achieved by precise interactions between male and female reproductive organs. In plant fertilization, sperm cells are carried to ovules by pollen tubes. Signals from the pistil are involved in elongation and control of the direction of the pollen tube. Genetic, reverse genetic, and cell biological analyses using model plants have identified various factors related to the regulation of pollen tube growth and guidance. In this review, I summarize the mechanisms and molecules controlling pollen tube growth to the ovule, micropylar guidance, reception of the guidance signal in the pollen tube, rupture of the pollen tube to release sperm cells, and cessation of the tube guidance signal. I also briefly introduce various techniques used to analyze pollen tube guidance in vitro.
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Affiliation(s)
- Masahiro M Kanaoka
- Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan.
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11
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Wasąg P, Suwińska A, Zakrzewski P, Walczewski J, Lenartowski R, Lenartowska M. Calreticulin localizes to plant intra/extracellular peripheries of highly specialized cells involved in pollen-pistil interactions. PROTOPLASMA 2018; 255:57-67. [PMID: 28620697 PMCID: PMC5756280 DOI: 10.1007/s00709-017-1134-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 06/05/2017] [Indexed: 05/11/2023]
Abstract
Calcium (Ca2+) plays essential roles in generative reproduction of angiosperms, but the sites and mechanisms of Ca2+ storage and mobilization during pollen-pistil interactions have not been fully defined. Both external and internal Ca2+ stores are likely important during male gametophyte communication with the sporophytic and gametophytic cells within the pistil. Given that calreticulin (CRT), a Ca2+-buffering protein, is able to bind Ca2+ reversibly, it can serve as a mobile store of easily releasable Ca2+ (so called an exchangeable Ca2+) in eukaryotic cells. CRT has typical endoplasmic reticulum (ER) targeting and retention signals and resides primarily in the ER. However, localization of this protein outside the ER has also been revealed in both animal and plant cells, including Golgi/dictyosomes, nucleus, plasma membrane/cell surface, plasmodesmata, and even extracellular matrix. These findings indicate that CRT may function in a variety of different cell compartments and specialized structures. We have recently shown that CRT is highly expressed and accumulated in the ER of plant cells involved in pollen-pistil interactions in Petunia, and we proposed an essential role for CRT in intracellular Ca2+ storage and mobilization during the key reproductive events. Here, we demonstrate that both CRT and exchangeable Ca2+ are localized in the intra/extracellular peripheries of highly specialized plant cells, such as the pistil transmitting tract cells, pollen tubes, nucellus cells surrounding the embryo sac, and synergids. Based on our present results, we propose that extracellularly located CRT is also involved in Ca2+ storage and mobilization during sexual reproduction of angiosperms.
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Affiliation(s)
- Piotr Wasąg
- Laboratory of Isotope and Instrumental Analysis, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University in Toruń, Toruń, Poland
| | - Anna Suwińska
- Laboratory of Developmental Biology, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University in Toruń, Toruń, Poland
| | - Przemysław Zakrzewski
- Laboratory of Developmental Biology, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University in Toruń, Toruń, Poland
| | - Jakub Walczewski
- Department of Plant Pathology, Plant Breeding and Acclimatization Institute, National Research Institute, Radzików, Poland
| | - Robert Lenartowski
- Laboratory of Isotope and Instrumental Analysis, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University in Toruń, Toruń, Poland
| | - Marta Lenartowska
- Laboratory of Developmental Biology, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University in Toruń, Toruń, Poland.
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12
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Pereira AM, Lopes AL, Coimbra S. Arabinogalactan Proteins as Interactors along the Crosstalk between the Pollen Tube and the Female Tissues. FRONTIERS IN PLANT SCIENCE 2016; 7:1895. [PMID: 28018417 PMCID: PMC5159419 DOI: 10.3389/fpls.2016.01895] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 11/30/2016] [Indexed: 05/19/2023]
Abstract
Arabinogalactan proteins (AGPs) have long been considered to be implicated in several steps of the reproductive process of flowering plants. Pollen tube growth along the pistil tissues requires a multiplicity of signaling pathways to be activated and turned off precisely, at crucial timepoints, to guarantee successful fertilization and seed production. In the recent years, an outstanding effort has been made by the plant reproduction scientific community in order to better understand this process. This resulted in the discovery of a fairly substantial number of new players essential for reproduction, as well as their modes of action and interactions. Besides all the indications of AGPs involvement in reproduction, there were no convincing evidences about it. Recently, several studies came out to prove what had long been suggested about this complex family of glycoproteins. AGPs consist of a large family of hydroxyproline-rich proteins, predicted to be anchored to the plasma membrane and extremely rich in sugars. These two last characteristics always made them perfect candidates to be involved in signaling mechanisms, in several plant developmental processes. New findings finally relate AGPs to concrete functions in plant reproduction. In this review, it is intended not only to describe how different molecules and signaling pathways are functioning to achieve fertilization, but also to integrate the recent discoveries about AGPs along this process.
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Affiliation(s)
- Ana M. Pereira
- Departamento de Biologia, Faculdade de Ciências da Universidade do PortoPorto, Portugal
- Biosystems and Integrative Sciences InstitutePorto, Portugal
| | - Ana L. Lopes
- Departamento de Biologia, Faculdade de Ciências da Universidade do PortoPorto, Portugal
- Biosystems and Integrative Sciences InstitutePorto, Portugal
| | - Sílvia Coimbra
- Departamento de Biologia, Faculdade de Ciências da Universidade do PortoPorto, Portugal
- Biosystems and Integrative Sciences InstitutePorto, Portugal
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13
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Abstract
Compared with the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells). Sperm cell release from the pollen tube occurs after intensive communication between the pollen tube cell and the receptive synergid, culminating in the lysis of both interaction partners. Following release of the two sperm cells, they interact and fuse with two dimorphic female gametes (the egg and the central cell) forming the major seed components embryo and endosperm, respectively. This process is known as double fertilization. Here, we review the current understanding of the processes of sperm cell reception, gamete interaction, their pre-fertilization activation and fusion, as well as the mechanisms plants use to prevent the fusion of egg cells with multiple sperm cells. The role of Ca(2+) is highlighted in these various processes and comparisons are drawn between fertilization mechanisms in flowering plants and other eukaryotes, including mammals.
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Affiliation(s)
- Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany.
| | - Stefanie Sprunck
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany
| | - Gary M Wessel
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912, USA
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14
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Pereira AM, Nobre MS, Pinto SC, Lopes AL, Costa ML, Masiero S, Coimbra S. "Love Is Strong, and You're so Sweet": JAGGER Is Essential for Persistent Synergid Degeneration and Polytubey Block in Arabidopsis thaliana. MOLECULAR PLANT 2016; 9:601-14. [PMID: 26774620 DOI: 10.1016/j.molp.2016.01.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 12/11/2015] [Accepted: 01/06/2016] [Indexed: 05/05/2023]
Abstract
Successful double fertilization and subsequent seed development in flowering plants requires the delivery of two sperm cells, transported by a pollen tube, into the embryo sac of an ovule. The embryo sac cells tightly control synergid cell death, and as a result the polyspermy block. Arabinogalactan proteins are highly glycosylated proteins thought to be involved in several steps of the reproductive process. We show that JAGGER, Arabinogalactan Protein 4, is an important molecule necessary to prevent the growth of multiple pollen tubes into one embryo sac in Arabidopsis thaliana. In jagger, an AGP4 knockout mutant, the pistils show impaired pollen tube blockage as a consequence of the survival of the persistent synergid. JAGGER seems to be involved in the signaling pathway that leads to a blockage of pollen tube attraction. Our results shed light on the mechanism responsible for preventing polyspermy in Arabidopsis and for safeguarding successful fertilization of all ovules in one pistil, ensuring seed set and the next generation.
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Affiliation(s)
- Ana Marta Pereira
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal; Plant Functional Genomics Group, Biosystems and Integrative Sciences Institute (BioISI), 4169-007 Porto, Portugal
| | - Margarida Sofia Nobre
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal; Plant Functional Genomics Group, Biosystems and Integrative Sciences Institute (BioISI), 4169-007 Porto, Portugal
| | - Sara Cristina Pinto
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal; Plant Functional Genomics Group, Biosystems and Integrative Sciences Institute (BioISI), 4169-007 Porto, Portugal
| | - Ana Lúcia Lopes
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal; Plant Functional Genomics Group, Biosystems and Integrative Sciences Institute (BioISI), 4169-007 Porto, Portugal
| | - Mário Luís Costa
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal; Plant Functional Genomics Group, Biosystems and Integrative Sciences Institute (BioISI), 4169-007 Porto, Portugal
| | - Simona Masiero
- Dipartimento di BioScienze, Università degli Studi di Milano, 20133 Milan, Italy
| | - Sílvia Coimbra
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal; Plant Functional Genomics Group, Biosystems and Integrative Sciences Institute (BioISI), 4169-007 Porto, Portugal.
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15
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Kanaoka MM, Higashiyama T. Peptide signaling in pollen tube guidance. CURRENT OPINION IN PLANT BIOLOGY 2015; 28:127-36. [PMID: 26580200 DOI: 10.1016/j.pbi.2015.10.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 10/14/2015] [Accepted: 10/15/2015] [Indexed: 05/05/2023]
Abstract
Fertilization is an important life event for sexually reproductive plants. Part of this process involves precise regulation of a series of complicated cell-cell communications between male and female tissues. Through genetic and omics approaches, many genes and proteins involved in this process have been identified. Here we review our current understanding of signaling components during fertilization. We will especially focus on LURE peptides and related signaling events that are required for micropylar pollen tube guidance. We will also summarize signaling events required for termination of micropylar pollen tube guidance after fertilization.
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Affiliation(s)
- Masahiro M Kanaoka
- Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
| | - Tetsuya Higashiyama
- Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan; JST, ERATO, Higashiyama Live-Holonics Project, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan; Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan.
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16
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Qu LJ, Li L, Lan Z, Dresselhaus T. Peptide signalling during the pollen tube journey and double fertilization. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:5139-50. [PMID: 26068467 DOI: 10.1093/jxb/erv275] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Flowering seed plants (angiosperms) have evolved unique ways to protect their gametes from pathogen attack and from drying out. The female gametes (egg and central cell) are deeply embedded in the maternal tissues of the ovule inside the ovary, while the male gametes (sperm cells) are enclosed in the vegetative pollen tube cell. After germination of the pollen tube at the surface of papilla cells of the stigma the two immobile sperm cells are transported deep inside the sporophytic maternal tissues to be released inside the ovule for double fertilization. Angiosperms have evolved a number of hurdles along the pollen tube journey to prevent inbreeding and fertilization by alien sperm cells, and to maximize reproductive success. These pre-zygotic hybridization barriers require intensive communication between the male and female reproductive cells and the necessity to distinguish self from non-self interaction partners. General molecules such as nitric oxide (NO) or gamma-aminobutyric acid (GABA) therefore appear to play only a minor role in these species-specific communication events. The past 20 years have shown that highly polymorphic peptides play a leading role in all communication steps along the pollen tube pathway and fertilization. Here we review our current understanding of the role of peptides during reproduction with a focus on peptide signalling during self-incompatibility, pollen tube growth and guidance as well as sperm reception and gamete activation.
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Affiliation(s)
- Li-Jia Qu
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, China
| | - Ling Li
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, China
| | - Zijun Lan
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, China
| | - Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93053 Regensburg, Germany
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17
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Kawashima T, Berger F. The central cell nuclear position at the micropylar end is maintained by the balance of F-actin dynamics, but dispensable for karyogamy in Arabidopsis. PLANT REPRODUCTION 2015; 28:103-10. [PMID: 25698518 DOI: 10.1007/s00497-015-0259-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 02/09/2015] [Indexed: 05/20/2023]
Abstract
Advances in Fertilization. In flowering plants, fertilization is initiated by the delivery of immotile sperm cells to the boundary between two female gametes, the egg cell and the central cell. During female gamete development in Arabidopsis, the nucleus of the central cell becomes positioned toward this boundary. How this specific polarized nuclear position is maintained is unclear and whether it plays a role in successful fertilization remains to be determined. By disrupting and manipulating F-actin dynamics in the central cell, we identified that the balance of F-actin dynamics is important for nuclear positioning in the central cell and that the presence of intact F-actin cables in the central cell correlates with successful karyogamy regardless of the central cell nuclear position. We also report that the surface of the central cell nucleus is enriched in F-actin. Thus, the central cell nucleus might also serve as a site that organizes F-actin cytoskeleton to promote sperm cell nucleus movement and karyogamy.
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18
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Lindner H, Kessler SA, Müller LM, Shimosato-Asano H, Boisson-Dernier A, Grossniklaus U. TURAN and EVAN mediate pollen tube reception in Arabidopsis Synergids through protein glycosylation. PLoS Biol 2015; 13:e1002139. [PMID: 25919390 PMCID: PMC4412406 DOI: 10.1371/journal.pbio.1002139] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 03/19/2015] [Indexed: 11/18/2022] Open
Abstract
Pollen tube (PT) reception in flowering plants describes the crosstalk between the male and female gametophytes upon PT arrival at the synergid cells of the ovule. It leads to PT growth arrest, rupture, and sperm cell release, and is thus essential to ensure double fertilization. Here, we describe TURAN (TUN) and EVAN (EVN), two novel members of the PT reception pathway that is mediated by the FERONIA (FER) receptor-like kinase (RLK). Like fer, mutations in these two genes lead to PT overgrowth inside the female gametophyte (FG) without PT rupture. Mapping by next-generation sequencing, cytological analysis of reporter genes, and biochemical assays of glycoproteins in RNAi knockdown mutants revealed both genes to be involved in protein N-glycosylation in the endoplasmic reticulum (ER). TUN encodes a uridine diphosphate (UDP)-glycosyltransferase superfamily protein and EVN a dolichol kinase. In addition to their common role during PT reception in the synergids, both genes have distinct functions in the pollen: whereas EVN is essential for pollen development, TUN is required for PT growth and integrity by affecting the stability of the pollen-specific FER homologs ANXUR1 (ANX1) and ANX2. ANX1- and ANX2-YFP reporters are not expressed in tun pollen grains, but ANX1-YFP is degraded via the ER-associated degradation (ERAD) pathway, likely underlying the anx1/2-like premature PT rupture phenotype of tun mutants. Thus, as in animal sperm–egg interactions, protein glycosylation is essential for the interaction between the female and male gametophytes during PT reception to ensure fertilization and successful reproduction. Protein glycosylation is essential for gametophyte interactions between the male pollen tube and the female ovule in plants, reminiscent of gamete interactions during fertilization in mammals. In flowering plants, gametes are produced by the haploid, multicellular male (pollen), and female (embryo sac) gametophytes, which develop within the reproductive organs of the flower. Successful fertilization depends on delivery of the sperm cells to the embryo sac, which is embedded in the ovule, by the pollen tube. Upon arrival of the pollen tube at the opening of the ovule, crosstalk between male and female gametophytes, known as pollen tube reception, ensues; the pollen tube slows or stops its growth, then resumes rapid growth, and finally bursts to release the sperm cells and effect double fertilization. Although several members of the pollen tube reception pathway, including the receptor-like kinase FERONIA, have been identified, the molecular mechanisms underlying this communication process remain unclear. Here, we show that protein N-glycosylation is required for normal pollen tube reception. A mutant screen identified two genes, TURAN and EVAN, which are involved in protein N-glycosylation in the endoplasmic reticulum. Both genes act in the FERONIA-mediated pollen tube reception pathway, which is impaired in these mutants. Thus, in plants, a “dual recognition system,” involving interactions between both protein and glycosyl residues on the surface of male and female gametophytes, appears to be required for successful pollen tube reception, conceptually similar to sperm–egg interactions in mammals, for which N-glycosylation of cell surface proteins also plays an important role.
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Affiliation(s)
- Heike Lindner
- Institute of Plant Biology & Zurich-Basel Plant Science Center, University of Zurich, CH-8008 Zürich, Switzerland
| | - Sharon A. Kessler
- Institute of Plant Biology & Zurich-Basel Plant Science Center, University of Zurich, CH-8008 Zürich, Switzerland
| | - Lena M. Müller
- Institute of Plant Biology & Zurich-Basel Plant Science Center, University of Zurich, CH-8008 Zürich, Switzerland
| | - Hiroko Shimosato-Asano
- Institute of Plant Biology & Zurich-Basel Plant Science Center, University of Zurich, CH-8008 Zürich, Switzerland
| | - Aurélien Boisson-Dernier
- Institute of Plant Biology & Zurich-Basel Plant Science Center, University of Zurich, CH-8008 Zürich, Switzerland
| | - Ueli Grossniklaus
- Institute of Plant Biology & Zurich-Basel Plant Science Center, University of Zurich, CH-8008 Zürich, Switzerland
- * E-mail:
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19
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Higashiyama T, Takeuchi H. The mechanism and key molecules involved in pollen tube guidance. ANNUAL REVIEW OF PLANT BIOLOGY 2015; 66:393-413. [PMID: 25621518 DOI: 10.1146/annurev-arplant-043014-115635] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
During sexual reproduction of flowering plants, pollen tube guidance by pistil tissue is critical for the delivery of nonmotile sperm cells to female gametes. Multistep controls of pollen tube guidance can be divided into two phases: preovular guidance and ovular guidance. During preovular guidance, various female molecules, including stimulants for pollen germination and pollen tube growth, are provided to support tube growth toward the ovary, where the ovules are located. After entering the ovary, pollen tubes receive directional cues from their respective target ovules, including attractant peptides for precise, species-preferential attraction. Successful pollen tube guidance in the pistil requires not only nutritional and directional controls but also competency controls to make pollen tubes responsive to guidance cues, regulation to terminate growth once a pollen tube arrives at the target, and strategies to stop ovular attraction depending on the fertilization of female gametes.
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20
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Song X, Yuan L, Sundaresan V. Antipodal cells persist through fertilization in the female gametophyte of Arabidopsis. PLANT REPRODUCTION 2014; 27:197-203. [PMID: 25389024 DOI: 10.1007/s00497-014-0251-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2014] [Accepted: 10/29/2014] [Indexed: 05/09/2023]
Abstract
The female gametophyte of most flowering plants forms four cell types after cellularization, namely synergid cell, egg cell, central cell and antipodal cell. Of these, only the antipodal cells have no established functions, and it has been proposed that in many plants including Arabidopsis, the antipodal cells undergo programmed cell death during embryo sac maturation and prior to fertilization. Here, we examined the expression of female gametophyte-specific fluorescent reporters in mature embryo sacs of Arabidopsis, and in developing seeds shortly after fertilization. We observed expression of the fluorescence from the reporter genes in the three antipodal cells in the mature stage embryo sac, and continuing through the early syncytial endosperm stages. These observations suggest that rather than undergoing programmed cell death and degenerating at the mature stage of female gametophyte as previously supposed, the antipodal cells in Arabidopsis persist beyond fertilization, even when the other cell types are no longer present. The results support the concept that the Arabidopsis female gametophyte at maturity should be considered to be composed of seven cells and four cell types, rather than the previously prevailing view of four cells and three cell types.
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Affiliation(s)
- Xiaoya Song
- Department of Plant Biology, University of California-Davis, One Shields Ave., Davis, CA, 95616, USA
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21
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Male-female communication triggers calcium signatures during fertilization in Arabidopsis. Nat Commun 2014; 5:4645. [PMID: 25145880 PMCID: PMC4143946 DOI: 10.1038/ncomms5645] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 07/09/2014] [Indexed: 12/11/2022] Open
Abstract
Cell-cell communication and interaction is critical during fertilization and triggers free cytosolic calcium ([Ca2+]cyto) as a key signal for egg activation and a polyspermy block in animal oocytes. Fertilization in flowering plants is more complex, involving interaction of a pollen tube with egg adjoining synergid cells, culminating in release of two sperm cells and their fusion with the egg and central cell, respectively. Here, we report the occurrence and role of [Ca2+]cyto signals during the entire double fertilization process in Arabidopsis. [Ca2+]cyto oscillations are initiated in synergid cells after physical contact with the pollen tube apex. In egg and central cells, a short [Ca2+]cyto transient is associated with pollen tube burst and sperm cell arrival. A second extended [Ca2+]cyto transient solely in the egg cell is correlated with successful fertilization. Thus, each female cell type involved in double fertilization displays a characteristic [Ca2+]cyto signature differing by timing and behaviour from [Ca2+]cyto waves reported in mammals.
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22
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Heydlauff J, Groß-Hardt R. Love is a battlefield: programmed cell death during fertilization. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:1323-30. [PMID: 24567492 DOI: 10.1093/jxb/eru030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Plant development and growth is sustained by the constant generation of tremendous amounts of cells, which become integrated into various types of tissues and organs. What is all too often overlooked is that this thriving life also requires the targeted degeneration of selected cells, which undergo cell death according to genetically encoded programmes or environmental stimuli. The side-by-side existence of generation and demise is particularly evident in the haploid phase of the flowering plants cycle. Here, the lifespan of terminally differentiated accessory cells contrasts with that of germ cells, which by definition live on to form the next generation. In fact, with research in recent years it is becoming increasingly clear that the gametophytes of flowering plants constitute an attractive and powerful system for investigating the molecular mechanisms underlying selective cell death.
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Affiliation(s)
- Juliane Heydlauff
- Center for Plant Molecular Biology (ZMBP), University of Tuebingen, Auf der Morgenstelle 1, D-72076 Tübingen, Germany
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23
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Bleckmann A, Alter S, Dresselhaus T. The beginning of a seed: regulatory mechanisms of double fertilization. FRONTIERS IN PLANT SCIENCE 2014; 5:452. [PMID: 25309552 PMCID: PMC4160995 DOI: 10.3389/fpls.2014.00452] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 08/21/2014] [Indexed: 05/20/2023]
Abstract
THE LAUNCH OF SEED DEVELOPMENT IN FLOWERING PLANTS (ANGIOSPERMS) IS INITIATED BY THE PROCESS OF DOUBLE FERTILIZATION: two male gametes (sperm cells) fuse with two female gametes (egg and central cell) to form the precursor cells of the two major seed components, the embryo and endosperm, respectively. The immobile sperm cells are delivered by the pollen tube toward the ovule harboring the female gametophyte by species-specific pollen tube guidance and attraction mechanisms. After pollen tube burst inside the female gametophyte, the two sperm cells fuse with the egg and central cell initiating seed development. The fertilized central cell forms the endosperm while the fertilized egg cell, the zygote, will form the actual embryo and suspensor. The latter structure connects the embryo with the sporophytic maternal tissues of the developing seed. The underlying mechanisms of double fertilization are tightly regulated to ensure delivery of functional sperm cells and the formation of both, a functional zygote and endosperm. In this review we will discuss the current state of knowledge about the processes of directed pollen tube growth and its communication with the synergid cells resulting in pollen tube burst, the interaction of the four gametes leading to cell fusion and finally discuss mechanisms how flowering plants prevent multiple sperm cell entry (polyspermy) to maximize their reproductive success.
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Affiliation(s)
- Andrea Bleckmann
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of RegensburgRegensburg, Germany
| | - Svenja Alter
- Plant Breeding, Center of Life and Food Sciences Weihenstephan, Technische Universität MünchenFreising, Germany
| | - Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of RegensburgRegensburg, Germany
- *Correspondence: Thomas Dresselhaus, Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, Universitätsstrasse 18, 93053 Regensburg, Germany e-mail:
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24
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Beale KM, Johnson MA. Speed dating, rejection, and finding the perfect mate: advice from flowering plants. CURRENT OPINION IN PLANT BIOLOGY 2013; 16:590-7. [PMID: 24021868 DOI: 10.1016/j.pbi.2013.08.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 08/17/2013] [Accepted: 08/20/2013] [Indexed: 05/08/2023]
Abstract
Angiosperm pollen tubes extend through pistil tissue to deliver a pair of immotile sperm cells to female gametes for double fertilization. The extended journey of the pollen tube requires extensive cell:cell interactions that guide the pollen tube to its destination and instruct it to stop growing and burst. Once sperm cells are released the molecular exchanges between male and female continue, resulting in sperm activation and gamete fusion. Finally, there is evidence that gamete fusion can feed back on the pollen tube attraction mechanism so that additional pollen tubes can be attracted only if the first sperm cells fail to fertilize. We review progress toward defining the molecules mediating each of these exchanges and describe how small cysteine-rich peptides are a major mode of cellular communication.
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Affiliation(s)
- Kristin M Beale
- Brown University Department of Molecular Biology, Cell Biology, and Biochemistry, United States
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25
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Martín MV, Distefano AM, Zabaleta EJ, Pagnussat GC. New insights into the functional roles of reactive oxygen species during embryo sac development and fertilization in Arabidopsis thaliana. PLANT SIGNALING & BEHAVIOR 2013; 8:doi: 10.4161/psb.25714. [PMID: 23887494 PMCID: PMC4091057 DOI: 10.4161/psb.25714] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Previously considered as toxic by-products of aerobic metabolism, reactive oxygen species (ROS) are emerging as essential signaling molecules in eukaryotes. Recent evidence showed that maintenance of ROS homeostasis during female gametophyte development is crucial for embryo sac patterning and fertilization. Although ROS are exclusively detected in the central cell of mature embryo sacs, the study of mutants deficient in ROS homeostasis suggests that controlled oxidative bursts might take place earlier during gametophyte development. Also, a ROS burst that depends on pollination takes place inside the embryo sac. This oxidative response might be required for pollen tube growth arrest and for sperm cell release. In this mini-review, we will focus on new insights into the role of ROS during female gametophyte development and fertilization. Special focus will be made on the mitochondrial Mn-Superoxide dismutase (MSD1), which has been recently reported to be essential for maintaining ROS homeostasis during embryo sac formation.
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26
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Woriedh M, Wolf S, Márton ML, Hinze A, Gahrtz M, Becker D, Dresselhaus T. External application of gametophyte-specific ZmPMEI1 induces pollen tube burst in maize. PLANT REPRODUCTION 2013; 26:255-66. [PMID: 23824238 DOI: 10.1007/s00497-013-0221-z] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Accepted: 06/23/2013] [Indexed: 05/22/2023]
Abstract
Regulated demethylesterification of homogalacturonan, a major component of plant cell walls, by the activity of pectin methylesterases (PMEs), plays a critical role for cell wall stability and integrity. Especially fast growing plant cells such as pollen tubes secrete large amounts of PMEs toward their apoplasmic space. PME activity itself is tightly regulated by its inhibitor named as PME inhibitor and is thought to be required especially at the very pollen tube tip. We report here the identification and functional characterization of PMEI1 from maize (ZmPMEI1). We could show that the protein acts as an inhibitor of PME but not of invertases and found that its gene is strongly expressed in both gametophytes (pollen grain and embryo sac). Promoter reporter studies showed gene activity also during pollen tube growth toward and inside the transmitting tract. All embryo sac cells except the central cell displayed strong expression. Weaker signals were visible at sporophytic cells of the micropylar region. ZmPMEI1-EGFP fusion protein is transported within granules inside the tube and accumulates at the pollen tube tip as well as at sites where pollen tubes bend and/or change growth directions. The female gametophyte putatively influences pollen tube growth behavior by exposing it to ZmPMEI1. We therefore simulated this effect by applying recombinant protein at different concentrations on growing pollen tubes. ZmPMEI1 did not arrest growth, but destabilized the cell wall inducing burst. Compared with female gametophyte secreted defensin-like ZmES4, which induces burst at the very pollen tube tip, ZmPMEI1-induced burst occurs at the subapical region. These findings indicate that ZmPMEI1 secreted by the embryo sac likely destabilizes the pollen tube wall during perception and together with other proteins such as ZmES4 leads to burst and thus sperm release.
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Affiliation(s)
- Mayada Woriedh
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
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27
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Dresselhaus T, Franklin-Tong N. Male-female crosstalk during pollen germination, tube growth and guidance, and double fertilization. MOLECULAR PLANT 2013; 6:1018-36. [PMID: 23571489 DOI: 10.1093/mp/sst061] [Citation(s) in RCA: 197] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Sperm cells of flowering plants are non-motile and thus require transportation to the egg apparatus via the pollen tube to execute double fertilization. During its journey, the pollen tube interacts with various sporophytic cell types that support its growth and guide it towards the surface of the ovule. The final steps of tube guidance and sperm delivery are controlled by the cells of the female gametophyte. During fertilization, cell-cell communication events take place to achieve and maximize reproductive success. Additional layers of crosstalk exist, including self-recognition and specialized processes to prevent self-fertilization and consequent inbreeding. In this review, we focus on intercellular communication between the pollen grain/pollen tube including the sperm cells with the various sporophytic maternal tissues and the cells of the female gametophyte. Polymorphic-secreted peptides and small proteins, especially those belonging to various subclasses of small cysteine-rich proteins (CRPs), reactive oxygen species (ROS)/NO signaling, and the second messenger Ca(2+), play center stage in most of these processes.
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Affiliation(s)
- Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, Universitätsstraβe 31, D-93053 Regensburg, Germany.
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