1
|
Chandler JO, Wilhelmsson PKI, Fernandez-Pozo N, Graeber K, Arshad W, Pérez M, Steinbrecher T, Ullrich KK, Nguyen TP, Mérai Z, Mummenhoff K, Theißen G, Strnad M, Scheid OM, Schranz ME, Petřík I, Tarkowská D, Novák O, Rensing SA, Leubner-Metzger G. The dimorphic diaspore model Aethionema arabicum (Brassicaceae): Distinct molecular and morphological control of responses to parental and germination temperatures. THE PLANT CELL 2024; 36:2465-2490. [PMID: 38513609 PMCID: PMC11218780 DOI: 10.1093/plcell/koae085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 02/21/2024] [Accepted: 02/23/2024] [Indexed: 03/23/2024]
Abstract
Plants in habitats with unpredictable conditions often have diversified bet-hedging strategies that ensure fitness over a wider range of variable environmental factors. A striking example is the diaspore (seed and fruit) heteromorphism that evolved to maximize species survival in Aethionema arabicum (Brassicaceae) in which external and endogenous triggers allow the production of two distinct diaspores on the same plant. Using this dimorphic diaspore model, we identified contrasting molecular, biophysical, and ecophysiological mechanisms in the germination responses to different temperatures of the mucilaginous seeds (M+ seed morphs), the dispersed indehiscent fruits (IND fruit morphs), and the bare non-mucilaginous M- seeds obtained by pericarp (fruit coat) removal from IND fruits. Large-scale comparative transcriptome and hormone analyses of M+ seeds, IND fruits, and M- seeds provided comprehensive datasets for their distinct thermal responses. Morph-specific differences in co-expressed gene modules in seeds, as well as in seed and pericarp hormone contents, identified a role of the IND pericarp in imposing coat dormancy by generating hypoxia affecting abscisic acid (ABA) sensitivity. This involved expression of morph-specific transcription factors, hypoxia response, and cell wall remodeling genes, as well as altered ABA metabolism, transport, and signaling. Parental temperature affected ABA contents and ABA-related gene expression and altered IND pericarp biomechanical properties. Elucidating the molecular framework underlying the diaspore heteromorphism can provide insight into developmental responses to globally changing temperatures.
Collapse
Affiliation(s)
- Jake O Chandler
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Per K I Wilhelmsson
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg 35043, Germany
| | - Noe Fernandez-Pozo
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg 35043, Germany
- Institute for Mediterranean and Subtropical Horticulture “La Mayora” (IHSM-CSIC-UMA), Málaga 29010, Spain
| | - Kai Graeber
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Waheed Arshad
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Marta Pérez
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Tina Steinbrecher
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Kristian K Ullrich
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg 35043, Germany
| | - Thu-Phuong Nguyen
- Biosystematics Group, Wageningen University, PB Wageningen 6708, The Netherlands
| | - Zsuzsanna Mérai
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - Klaus Mummenhoff
- Department of Biology, Botany, University of Osnabrück, Osnabrück 49076, Germany
| | - Günter Theißen
- Matthias Schleiden Institute/Department of Genetics, Friedrich Schiller University Jena, Jena 07743, Germany
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
| | - Ortrun Mittelsten Scheid
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna 1030, Austria
| | - M Eric Schranz
- Biosystematics Group, Wageningen University, PB Wageningen 6708, The Netherlands
| | - Ivan Petřík
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
| | - Danuše Tarkowská
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
| | - Stefan A Rensing
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg 35043, Germany
- Centre for Biological Signalling Studies (BIOSS), University of Freiburg, Freiburg 79104, Germany
| | - Gerhard Leubner-Metzger
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
- Laboratory of Growth Regulators, Faculty of Science, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc 78371, Czech Republic
| |
Collapse
|
2
|
Carrera-Castaño G, Mira S, Fañanás-Pueyo I, Sánchez-Montesino R, Contreras Á, Weiste C, Dröge-Laser W, Gómez L, Oñate-Sánchez L. Complex control of seed germination timing by ERF50 involves RGL2 antagonism and negative feedback regulation of DOG1. THE NEW PHYTOLOGIST 2024; 242:2026-2042. [PMID: 38494681 DOI: 10.1111/nph.19681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 02/29/2024] [Indexed: 03/19/2024]
Abstract
Seed dormancy governs germination timing, with both evolutionary and applied consequences. Despite extensive studies on the hormonal and genetic control of these processes, molecular mechanisms directly linking dormancy and germination remain poorly understood. By screening a collection of lines overexpressing Arabidopsis transcription factors, we identified ERF50 as a key gene to control dormancy and germination. To study its regulation, we measured seed-related physiological parameters in loss-of-function mutants and carried out transactivation, protein interaction and ChIP-PCR analyses. We found direct ERF50-mediated repression of DOG1 and activation of EXPA2 transcription, which results in enhanced seed germination. Although ERF50 expression is increased by DOG1 in dormant seeds, ERF50 germination-promoting activity is blocked by RGL2. The physiological, genetic and molecular evidence gathered here supports that ERF50 controls germination timing by regulating DOG1 levels to leverage its role as enhancer of seed germination, via RGL2 antagonism on EXPA2 expression. Our results highlight the central role of ERF50 as a feedback regulator to couple and fine-tune seed dormancy and germination.
Collapse
Affiliation(s)
- Gerardo Carrera-Castaño
- Centro de Biotecnología y Genómica de Plantas (CBGP, UPM-INIA) Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA, CSIC), Campus de Montegancedo, Pozuelo de Alarcón, Madrid, 28223, Spain
| | - Sara Mira
- Centro de Biotecnología y Genómica de Plantas (CBGP, UPM-INIA) Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA, CSIC), Campus de Montegancedo, Pozuelo de Alarcón, Madrid, 28223, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid (UPM), Madrid, 28040, Spain
| | - Iris Fañanás-Pueyo
- Centro de Biotecnología y Genómica de Plantas (CBGP, UPM-INIA) Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA, CSIC), Campus de Montegancedo, Pozuelo de Alarcón, Madrid, 28223, Spain
| | - Rocío Sánchez-Montesino
- Centro de Biotecnología y Genómica de Plantas (CBGP, UPM-INIA) Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA, CSIC), Campus de Montegancedo, Pozuelo de Alarcón, Madrid, 28223, Spain
| | - Ángela Contreras
- Centro de Biotecnología y Genómica de Plantas (CBGP, UPM-INIA) Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA, CSIC), Campus de Montegancedo, Pozuelo de Alarcón, Madrid, 28223, Spain
| | - Christoph Weiste
- Department of Pharmaceutical Biology, Faculty of Biology, Biocenter, Julius-von-Sachs-Institute, Julius-Maximilians-Universität Würzburg, Würzburg, 97082, Germany
| | - Wolfgang Dröge-Laser
- Department of Pharmaceutical Biology, Faculty of Biology, Biocenter, Julius-von-Sachs-Institute, Julius-Maximilians-Universität Würzburg, Würzburg, 97082, Germany
| | - Luis Gómez
- Departamento de Sistemas y Recursos Naturales, Escuela Técnica Superior de Ingeniería de Montes, Forestal y del Medio Natural, 28040, Madrid, Spain
- Centro para la Conservación de la Biodiversidad y el Desarrollo Sostenible, Escuela Técnica Superior de Ingeniería de Montes, Forestal y del Medio Natural, Universidad Politécnica de Madrid, Madrid, 28040, Spain
| | - Luis Oñate-Sánchez
- Centro de Biotecnología y Genómica de Plantas (CBGP, UPM-INIA) Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA, CSIC), Campus de Montegancedo, Pozuelo de Alarcón, Madrid, 28223, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid (UPM), Madrid, 28040, Spain
| |
Collapse
|
3
|
Cui X, Zou M, Li J. Basally distributed actin array drives embryonic hypocotyl elongation during the seed-to-seedling transition in Arabidopsis. THE NEW PHYTOLOGIST 2023; 240:191-206. [PMID: 37537721 DOI: 10.1111/nph.19149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 06/27/2023] [Indexed: 08/05/2023]
Abstract
Seed germination is a vital developmental transition for the production of progeny by sexual reproduction in spermatophytes. The seed-to-seedling transition is predominately driven by hypocotyl cell elongation. However, the mechanism that underlies hypocotyl growth remains largely unknown. In this study, we characterized the actin array reorganization in embryonic hypocotyl epidermal cells. Live-cell imaging revealed a basally organized actin array formed during hypocotyl cell elongation. This polarized actin assembly is a barrel-shaped network, which comprises a backbone of longitudinally aligned actin cables and a fine actin cap linking these cables. We provide genetic evidence that the basal actin array formation requires formin-mediated actin polymerization and directional movement of actin filaments powered by myosin XIs. In fh1-1 and xi3ko mutants, actin filaments failed to reorganize into the basal actin array, and the hypocotyl cell elongation was inhibited compared with wild-type plants. Collectively, our work uncovers the molecular mechanisms for basal actin array assembly and demonstrates the connection between actin polarization and hypocotyl elongation during seed-to-seedling transition.
Collapse
Affiliation(s)
- Xuan Cui
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Minxia Zou
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Jiejie Li
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Science, Beijing Normal University, Beijing, 100875, China
- Key Laboratory of Cell Proliferation and Regulation of Ministry of Education, College of Life Science, Beijing Normal University, Beijing, 100875, China
| |
Collapse
|
4
|
Zaghdoud C, Ollio I, Solano CJ, Ochoa J, Suardiaz J, Fernández JA, Martínez Ballesta MDC. Red LED Light Improves Pepper ( Capsicum annuum L.) Seed Radicle Emergence and Growth through the Modulation of Aquaporins, Hormone Homeostasis, and Metabolite Remobilization. Int J Mol Sci 2023; 24:ijms24054779. [PMID: 36902208 PMCID: PMC10002511 DOI: 10.3390/ijms24054779] [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: 02/07/2023] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023] Open
Abstract
Red LED light (R LED) is an efficient tool to improve seed germination and plant growth under controlled environments since it is more readily absorbed by photoreceptors' phytochromes compared to other wavelengths of the spectrum. In this work, the effect of R LED on the radicle emergence and growth (Phase III of germination) of pepper seeds was evaluated. Thus, the impact of R LED on water transport through different intrinsic membrane proteins, via aquaporin (AQP) isoforms, was determined. In addition, the remobilization of distinct metabolites such as amino acids, sugars, organic acids, and hormones was analysed. R LED induced a higher germination speed index, regulated by an increased water uptake. PIP2;3 and PIP2;5 aquaporin isoforms were highly expressed and could contribute to a faster and more effective hydration of embryo tissues, leading to a reduction of the germination time. By contrast, TIP1;7, TIP1;8, TIP3;1 and TIP3;2 gene expressions were reduced in R LED-treated seeds, pointing to a lower need for protein remobilization. NIP4;5 and XIP1;1 were also involved in radicle growth but their role needs to be elucidated. In addition, R LED induced changes in amino acids and organic acids as well as sugars. Therefore, an advanced metabolome oriented to a higher energetic metabolism was observed, conditioning better seed germination performance together with a rapid water flux.
Collapse
Affiliation(s)
- Chokri Zaghdoud
- Bureau de Transfert de Technologie (BuTT), Université de Gafsa, Gafsa 2112, Tunisia
| | - Irene Ollio
- Ingeniería Agronómica, Technical University of Cartagena, Paseo Alfonso XIII 48, E-30203 Cartagena, Spain
- Recursos Fitogenéticos, Instituto de Biotecnología Vegetal, Edificio I+D+i, E-30202 Cartagena, Spain
| | - Cristóbal J. Solano
- División of Innovation in Telematic Systems and Electronic Technology (DINTEL), Technical University of Cartagena, Campus Muralla del Mar, s/n, E-30202 Cartagena, Spain
| | - Jesús Ochoa
- Ingeniería Agronómica, Technical University of Cartagena, Paseo Alfonso XIII 48, E-30203 Cartagena, Spain
- Recursos Fitogenéticos, Instituto de Biotecnología Vegetal, Edificio I+D+i, E-30202 Cartagena, Spain
| | - Juan Suardiaz
- División of Innovation in Telematic Systems and Electronic Technology (DINTEL), Technical University of Cartagena, Campus Muralla del Mar, s/n, E-30202 Cartagena, Spain
| | - Juan A. Fernández
- Ingeniería Agronómica, Technical University of Cartagena, Paseo Alfonso XIII 48, E-30203 Cartagena, Spain
- Recursos Fitogenéticos, Instituto de Biotecnología Vegetal, Edificio I+D+i, E-30202 Cartagena, Spain
| | - María del Carmen Martínez Ballesta
- Ingeniería Agronómica, Technical University of Cartagena, Paseo Alfonso XIII 48, E-30203 Cartagena, Spain
- Recursos Fitogenéticos, Instituto de Biotecnología Vegetal, Edificio I+D+i, E-30202 Cartagena, Spain
- Correspondence: ; Tel.: +34-968-325457
| |
Collapse
|
5
|
Montesinos Á, Dardick C, Rubio-Cabetas MJ, Grimplet J. Polymorphisms and gene expression in the almond IGT family are not correlated to variability in growth habit in major commercial almond cultivars. PLoS One 2021; 16:e0252001. [PMID: 34644299 PMCID: PMC8513883 DOI: 10.1371/journal.pone.0252001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 09/29/2021] [Indexed: 11/18/2022] Open
Abstract
Almond breeding programs aimed at selecting cultivars adapted to intensive orchards have recently focused on the optimization of tree architecture. This multifactorial trait is defined by numerous components controlled by processes such as hormonal responses, gravitropism and light perception. Gravitropism sensing is crucial to control the branch angle and therefore, the tree habit. A gene family, denominated IGT family after a shared conserved domain, has been described as involved in the regulation of branch angle in several species, including rice and Arabidopsis, and even in fruit trees like peach. Here we identified six members of this family in almond: LAZY1, LAZY2, TAC1, DRO1, DRO2, IGT-like. After analyzing their protein sequences in forty-one almond cultivars and wild species, little variability was found, pointing a high degree of conservation in this family. To our knowledge, this is the first effort to analyze the diversity of IGT family proteins in members of the same tree species. Gene expression was analyzed in fourteen cultivars of agronomical interest comprising diverse tree habit phenotypes. Only LAZY1, LAZY2 and TAC1 were expressed in almond shoot tips during the growing season. No relation could be established between the expression profile of these genes and the variability observed in the tree habit. However, some insight has been gained in how LAZY1 and LAZY2 are regulated, identifying the IPA1 almond homologues and other transcription factors involved in hormonal responses as regulators of their expression. Besides, we have found various polymorphisms that could not be discarded as involved in a potential polygenic origin of regulation of architectural phenotypes. Therefore, we have established that neither the expression nor the genetic polymorphism of IGT family genes are correlated to diversity of tree habit in currently commercialized almond cultivars, with other gene families contributing to the variability of these traits.
Collapse
Affiliation(s)
- Álvaro Montesinos
- Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Unidad de Hortofruticultura, Gobierno de Aragón, Avda. Montañana, Zaragoza, Spain
- Instituto Agroalimentario de Aragón–IA2 (CITA-Universidad de Zaragoza), Calle Miguel Servet, Zaragoza, Spain
| | - Chris Dardick
- Appalachian Fruit Research Station, United States Department of Agriculture—Agriculture Research Service, Kearneysville, WV, United States of America
| | - María José Rubio-Cabetas
- Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Unidad de Hortofruticultura, Gobierno de Aragón, Avda. Montañana, Zaragoza, Spain
- Instituto Agroalimentario de Aragón–IA2 (CITA-Universidad de Zaragoza), Calle Miguel Servet, Zaragoza, Spain
| | - Jérôme Grimplet
- Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Unidad de Hortofruticultura, Gobierno de Aragón, Avda. Montañana, Zaragoza, Spain
- Instituto Agroalimentario de Aragón–IA2 (CITA-Universidad de Zaragoza), Calle Miguel Servet, Zaragoza, Spain
| |
Collapse
|
6
|
Xue X, Yu YC, Wu Y, Xue H, Chen LQ. Locally restricted glucose availability in the embryonic hypocotyl determines seed germination under abscisic acid treatment. THE NEW PHYTOLOGIST 2021; 231:1832-1844. [PMID: 34032290 DOI: 10.1111/nph.17513] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/17/2021] [Indexed: 05/06/2023]
Abstract
Abiotic stresses affect plant growth and development by causing cellular damage and/or restricting resources. Plants often respond to stresses through abscisic acid (ABA) signaling. Exogenous ABA application can therefore be used to mimic stress responses, which can be overridden by glucose (Glc) addition during seed germination. It remains unclear whether ABA-mediated germination inhibition is due to regional or global suppression of Glc availability in germinating Arabidopsis seeds. We used a genetically engineered Förster resonance energy transfer (FRET) sensor to ascertain whether ABA affects the spatiotemporal distribution of Glc, 14 C-Glc uptake assays to track potential effects of ABA on sugar import, and transcriptome and mutant analyses to identify genes associated with Glc availability that are involved in ABA-inhibited seed germination. Abscisic acid limits Glc in the hypocotyl largely by suppressing sugar allocation as well as altering sugar metabolism. Mutant plants carrying loss-of-function ABA-inducible sucrose-phosphate synthase (SPS) genes accumulated more Glc, leading to ABA-insensitive germination. We reveal that Glc antagonizes ABA by globally counteracting the ABA influence at the transcript level, including expansin (EXP) family genes suppressed by ABA. This study presents a new perspective on how ABA affects Glc distribution, which likely reflects what occurs when seeds are subjected to abiotic stresses such as drought and salt stress.
Collapse
Affiliation(s)
- Xueyi Xue
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Institute for Sustainability, Energy, and Environment, University of Illinois Urbana, Urbana, IL, 61801, USA
| | - Ya-Chi Yu
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Yue Wu
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, China
| | - Huiling Xue
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, China
| | - Li-Qing Chen
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| |
Collapse
|
7
|
High-throughput image segmentation and machine learning approaches in the plant sciences across multiple scales. Emerg Top Life Sci 2021; 5:239-248. [DOI: 10.1042/etls20200273] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/09/2021] [Accepted: 02/11/2021] [Indexed: 01/12/2023]
Abstract
Agriculture has benefited greatly from the rise of big data and high-performance computing. The acquisition and analysis of data across biological scales have resulted in strategies modeling inter- actions between plant genotype and environment, models of root architecture that provide insight into resource utilization, and the elucidation of cell-to-cell communication mechanisms that are instrumental in plant development. Image segmentation and machine learning approaches for interpreting plant image data are among many of the computational methodologies that have evolved to address challenging agricultural and biological problems. These approaches have led to contributions such as the accelerated identification of gene that modulate stress responses in plants and automated high-throughput phenotyping for early detection of plant diseases. The continued acquisition of high throughput imaging across multiple biological scales provides opportunities to further push the boundaries of our understandings quicker than ever before. In this review, we explore the current state of the art methodologies in plant image segmentation and machine learning at the agricultural, organ, and cellular scales in plants. We show how the methodologies for segmentation and classification differ due to the diversity of physical characteristics found at these different scales. We also discuss the hardware technologies most commonly used at these different scales, the types of quantitative metrics that can be extracted from these images, and how the biological mechanisms by which plants respond to abiotic/biotic stresses or genotypic modifications can be extracted from these approaches.
Collapse
|
8
|
Zhai K, Zhao G, Jiang H, Sun C, Ren J. Overexpression of Maize ZmMYB59 Gene Plays a Negative Regulatory Role in Seed Germination in Nicotiana tabacum and Oryza sativa. FRONTIERS IN PLANT SCIENCE 2020; 11:564665. [PMID: 33013985 PMCID: PMC7516257 DOI: 10.3389/fpls.2020.564665] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/17/2020] [Indexed: 05/05/2023]
Abstract
MYB transcription factors are involved in many biological processes, including metabolism, stress response and plant development. In our previous work, ZmMYB59 was down-regulated by deep sowing during maize seed germination. However, there are few reports on seed germination regulated by MYB proteins. In this study, to examine its functions during seed germination, Agrobacterium-mediated transformation was exploited to generate ZmMYB59 overexpression (OE) tobacco and rice. In T2 generation transgenic tobacco, germination rate, germination index, vigor index and hypocotyl length were significantly decreased by 25.0-50.9, 34.5-54.4, 57.5-88.3, and 21.9-31.3% compared to wild-type (WT) lines. In T2 generation transgenic rice, above corresponding parameters were notably reduced by 39.1-53.8, 51.4-71.4, 52.5-74.0, and 28.3-41.5%, respectively. On this basis, antioxidant capacity and endogenous hormones were determined. The activities of catalase, peroxidase, superoxide dismutase, ascorbate peroxidase of OE lines were significantly lower than those of WT, suggesting that ZmMYB59 reduced their oxidation resistance. As well, ZmMYB59 overexpression extremely inhibited the synthesis of gibberellin A1 (GA1) and cytokinin (CTK), and promoted the synthesis of abscisic acid (ABA) concurrently. Taken together, it proposed that ZmMYB59 was a negative regulator during seed germination in tobacco and rice, which also contributes to illuminate the molecular mechanisms regulated by MYB transcription factors.
Collapse
Affiliation(s)
- Kaihui Zhai
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Agriculture and Food Science, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Guangwu Zhao
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Agriculture and Food Science, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Hongye Jiang
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Agriculture and Food Science, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Caixia Sun
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Agriculture and Food Science, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Jingyu Ren
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Agriculture and Food Science, Zhejiang Agriculture and Forestry University, Hangzhou, China
| |
Collapse
|
9
|
FRUITFULL Is a Repressor of Apical Hook Opening in Arabidopsis thaliana. Int J Mol Sci 2020; 21:ijms21176438. [PMID: 32899394 PMCID: PMC7504503 DOI: 10.3390/ijms21176438] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/24/2020] [Accepted: 08/31/2020] [Indexed: 12/04/2022] Open
Abstract
Plants adjust their architecture to a constantly changing environment, requiring adaptation of differential growth. Despite their importance, molecular switches, which define growth transitions, are largely unknown. Apical hook development in dark grown Arabidopsis thaliana (A. thaliana) seedlings serves as a suitable model for differential growth transition in plants. Here, we show that the phytohormone auxin counteracts the light-induced growth transition during apical hook opening. We, subsequently, identified genes which are inversely regulated by light and auxin. We used in silico analysis of the regulatory elements in this set of genes and subsequently used natural variation in gene expression to uncover correlations between underlying transcription factors and the in silico predicted target genes. This approach uncovered that MADS box transcription factor AGAMOUS-LIKE 8 (AGL8)/FRUITFULL (FUL) modulates apical hook opening. Our data shows that transient FUL expression represses the expression of growth stimulating genes during early phases of apical hook development and therewith guards the transition to growth promotion for apical hook opening. Here, we propose a role for FUL in setting tissue identity, thereby regulating differential growth during apical hook development.
Collapse
|
10
|
A Molecular Signal Integration Network Underpinning Arabidopsis Seed Germination. Curr Biol 2020; 30:3703-3712.e4. [PMID: 32763174 PMCID: PMC7544511 DOI: 10.1016/j.cub.2020.07.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 06/22/2020] [Accepted: 07/02/2020] [Indexed: 12/20/2022]
Abstract
Seed dormancy is an adaptive trait defining where and when plants are established. Diverse signals from the environment are used to decide when to initiate seed germination, a process driven by the expansion of cells within the embryo. How these signals are integrated and transduced into the biomechanical changes that drive embryo growth remains poorly understood. Using Arabidopsis seeds, we demonstrate that cell-wall-loosening EXPANSIN (EXPA) genes promote gibberellic acid (GA)-mediated germination, identifying EXPAs as downstream molecular targets of this developmental phase transition. Molecular interaction screening identified transcription factors (TFs) that bind to both EXPA promoter fragments and DELLA GA-response regulators. A subset of these TFs is targeted each by nitric oxide (NO) and the phytochrome-interacting TF PIL5. This molecular interaction network therefore directly links the perception of an external environmental signal (light) and internal hormonal signals (GA and NO) with downstream germination-driving EXPA gene expression. Experimental validation of this network established that many of these TFs mediate GA-regulated germination, including TCP14/15, RAP2.2/2.3/2.12, and ZML1. The reduced germination phenotype of the tcp14 tcp15 mutant seed was partially rescued through ectopic expression of their direct target EXPA9. The GA-mediated control of germination by TCP14/15 is regulated through EXPA-mediated control of cell wall loosening, providing a mechanistic explanation for this phenotype and a previously undescribed role for TCPs in the control of cell expansion. This network reveals the paths of signal integration that culminate in seed germination and provides a resource to uncover links between the genetic and biomechanical bases of plant growth. The network linking integration of environmental signals to seed growth is mapped EXPANSIN gene expression is redundantly regulated and promotes GA-mediated germination The TCP14 transcription factor directly regulates EXPANSIN9 expression The tcp14/15 germination phenotype is complemented by EXPANSIN9 expression
Collapse
|
11
|
The signalling role of ROS in the regulation of seed germination and dormancy. Biochem J 2020; 476:3019-3032. [PMID: 31657442 DOI: 10.1042/bcj20190159] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 10/04/2019] [Accepted: 10/04/2019] [Indexed: 12/11/2022]
Abstract
Reactive oxygen species (ROS) are versatile compounds which can have toxic or signalling effects in a wide range living organisms, including seeds. They have been reported to play a pivotal role in the regulation of seed germination and dormancy but their mechanisms of action are still far from being fully understood. In this review, we sum-up the major findings that have been carried out this last decade in this field of research and which altogether shed a new light on the signalling roles of ROS in seed physiology. ROS participate in dormancy release during seed dry storage through the direct oxidation of a subset of biomolecules. During seed imbibition, the controlled generation of ROS is involved in the perception and transduction of environmental conditions that control germination. When these conditions are permissive for germination, ROS levels are maintained at a level which triggers cellular events associated with germination, such as hormone signalling. Here we propose that the spatiotemporal regulation of ROS production acts in concert with hormone signalling to regulate the cellular events involved in cell expansion associated with germination.
Collapse
|
12
|
Carrera-Castaño G, Calleja-Cabrera J, Pernas M, Gómez L, Oñate-Sánchez L. An Updated Overview on the Regulation of Seed Germination. PLANTS 2020; 9:plants9060703. [PMID: 32492790 PMCID: PMC7356954 DOI: 10.3390/plants9060703] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/22/2020] [Accepted: 05/26/2020] [Indexed: 02/07/2023]
Abstract
The ability of a seed to germinate and establish a plant at the right time of year is of vital importance from an ecological and economical point of view. Due to the fragility of these early growth stages, their swiftness and robustness will impact later developmental stages and crop yield. These traits are modulated by a continuous interaction between the genetic makeup of the plant and the environment from seed production to germination stages. In this review, we have summarized the established knowledge on the control of seed germination from a molecular and a genetic perspective. This serves as a “backbone” to integrate the latest developments in the field. These include the link of germination to events occurring in the mother plant influenced by the environment, the impact of changes in the chromatin landscape, the discovery of new players and new insights related to well-known master regulators. Finally, results from recent studies on hormone transport, signaling, and biophysical and mechanical tissue properties are underscoring the relevance of tissue-specific regulation and the interplay of signals in this crucial developmental process.
Collapse
|
13
|
Liu W, Lyu T, Xu L, Hu Z, Xiong X, Liu T, Cao J. Complex Molecular Evolution and Expression of Expansin Gene Families in Three Basic Diploid Species of Brassica. Int J Mol Sci 2020; 21:ijms21103424. [PMID: 32408673 PMCID: PMC7279145 DOI: 10.3390/ijms21103424] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/07/2020] [Accepted: 05/11/2020] [Indexed: 12/12/2022] Open
Abstract
Expansins are a kind of structural proteins of the plant cell wall, and they enlarge cells by loosening the cell walls. Therefore, expansins are involved in many growth and development processes. The complete genomic sequences of Brassica rapa, Brassica oleracea and Brassica nigra provide effective platforms for researchers to study expansin genes, and can be compared with analogues in Arabidopsis thaliana. This study identified and characterized expansin families in B. rapa, B. oleracea, and B. nigra. Through the comparative analysis of phylogeny, gene structure, and physicochemical properties, the expansin families were divided into four subfamilies, and then their expansion patterns and evolution details were explored accordingly. Results showed that after the three species underwent independent evolution following their separation from A. thaliana, the expansin families in the three species had increased similarities but fewer divergences. By searching divergences of promoters and coding sequences, significant positive correlations were revealed among orthologs in A. thaliana and the three basic species. Subsequently, differential expressions indicated extensive functional divergences in the expansin families of the three species, especially in reproductive development. Hence, these results support the molecular evolution of basic Brassica species, potential functions of these genes, and genetic improvement of related crops.
Collapse
Affiliation(s)
- Weimiao Liu
- Laboratory of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China; (W.L.); (T.L.); (L.X.); (Z.H.); (X.X.); (T.L.)
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, China
| | - Tianqi Lyu
- Laboratory of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China; (W.L.); (T.L.); (L.X.); (Z.H.); (X.X.); (T.L.)
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, China
| | - Liai Xu
- Laboratory of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China; (W.L.); (T.L.); (L.X.); (Z.H.); (X.X.); (T.L.)
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, China
| | - Ziwei Hu
- Laboratory of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China; (W.L.); (T.L.); (L.X.); (Z.H.); (X.X.); (T.L.)
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, China
| | - Xingpeng Xiong
- Laboratory of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China; (W.L.); (T.L.); (L.X.); (Z.H.); (X.X.); (T.L.)
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, China
| | - Tingting Liu
- Laboratory of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China; (W.L.); (T.L.); (L.X.); (Z.H.); (X.X.); (T.L.)
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, China
| | - Jiashu Cao
- Laboratory of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China; (W.L.); (T.L.); (L.X.); (Z.H.); (X.X.); (T.L.)
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, China
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Hangzhou 310058, China
- Correspondence: ; Tel.: +86-571-8898-2597
| |
Collapse
|
14
|
Yan H, Chaumont N, Gilles JF, Bolte S, Hamant O, Bailly C. Microtubule self-organisation during seed germination in Arabidopsis. BMC Biol 2020; 18:44. [PMID: 32354334 PMCID: PMC7191766 DOI: 10.1186/s12915-020-00774-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 03/26/2020] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Upon water uptake and release of seed dormancy, embryonic plant cells expand, while being mechanically constrained by the seed coat. Cortical microtubules (CMTs) are key players of cell elongation in plants: their anisotropic orientation channels the axis of cell elongation through the guidance of oriented deposition of load-bearing cellulose microfibrils in the cell wall. Interestingly, CMTs align with tensile stress, and consistently, they reorient upon compressive stress in growing hypocotyls. How CMTs first organise in germinating embryos is unknown, and their relation with mechanical stress has not been investigated at such an early developing stage. RESULTS Here, we analysed CMT dynamics in dormant and non-dormant Arabidopsis seeds by microscopy of fluorescently tagged microtubule markers at different developmental time points and in response to abscisic acid and gibberellins. We found that CMTs first appear as very few thick bundles in dormant seeds. Consistently, analysis of available transcriptome and translatome datasets show that limiting amounts of tubulin and microtubule regulators initially hinder microtubule self-organisation. Seeds imbibed in the presence of gibberellic acid or abscisic acid displayed altered microtubule organisation and transcriptional regulation. Upon the release of dormancy, CMTs then self-organise into multiple parallel transverse arrays. Such behaviour matches the tensile stress patterns in such mechanically constrained embryos. This suggests that, as CMTs first self-organise, they also align with shape-derived tensile stress patterns. CONCLUSIONS Our results provide a scenario in which dormancy release in the embryo triggers microtubule self-organisation and alignment with tensile stress prior to germination and anisotropic growth.
Collapse
Affiliation(s)
- Huifang Yan
- Laboratoire de Biologie du Développement, Sorbonne Université, CNRS, F-75005, Paris, France
- Key Laboratory of Pratacultural Science, Beijing Municipality, China Agricultural University, Beijing, 100193, China
- Grassland Agri-Husbandry Research Center, College of Grassland Science, Qingdao Agricultural University, Qingdao, 266109, China
| | - Nicole Chaumont
- Laboratoire de Biologie du Développement, Sorbonne Université, CNRS, F-75005, Paris, France
| | - Jean François Gilles
- Imaging Core Facility, CNRS-FRE3631-Institut de Biologie Paris Seine, Sorbonne Université, F-75005, Paris, France
| | - Susanne Bolte
- Imaging Core Facility, CNRS-FRE3631-Institut de Biologie Paris Seine, Sorbonne Université, F-75005, Paris, France
| | - Olivier Hamant
- Laboratoire de Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, F-69000, Lyon, France
| | - Christophe Bailly
- Laboratoire de Biologie du Développement, Sorbonne Université, CNRS, F-75005, Paris, France.
| |
Collapse
|
15
|
Hoai PTT, Tyerman SD, Schnell N, Tucker M, McGaughey SA, Qiu J, Groszmann M, Byrt CS. Deciphering aquaporin regulation and roles in seed biology. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:1763-1773. [PMID: 32109278 DOI: 10.1093/jxb/erz555] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 02/26/2020] [Indexed: 05/25/2023]
Abstract
Seeds are the typical dispersal and propagation units of angiosperms and gymnosperms. Water movement into and out of seeds plays a crucial role from the point of fertilization through to imbibition and seed germination. A class of membrane intrinsic proteins called aquaporins (AQPs) assist with the movement of water and other solutes within seeds. These highly diverse and abundant proteins are associated with different processes in the development, longevity, imbibition, and germination of seed. However, there are many AQPs encoded in a plant's genome and it is not yet clear how, when, or which AQPs are involved in critical stages of seed biology. Here we review the literature to examine the evidence for AQP involvement in seeds and analyse Arabidopsis seed-related transcriptomic data to assess which AQPs are likely to be important in seed water relations and explore additional roles for AQPs in seed biology.
Collapse
Affiliation(s)
- Phan T T Hoai
- Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
- School of Agriculture, Food and Wine, and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
- Faculty of Agriculture and Forestry, Tay Nguyen University, Dak Lak, Viet Nam
| | - Stephen D Tyerman
- Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
- School of Agriculture, Food and Wine, and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
| | - Nicholas Schnell
- School of Agriculture, Food and Wine, and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
| | - Matthew Tucker
- School of Agriculture, Food and Wine, and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
| | - Samantha A McGaughey
- Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
- School of Agriculture, Food and Wine, and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
| | - Jiaen Qiu
- Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
- School of Agriculture, Food and Wine, and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
| | - Michael Groszmann
- Australian Research Council Centre of Excellence for Translational Photosynthesis, Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Caitlin S Byrt
- Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
- School of Agriculture, Food and Wine, and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, Australia
- Australian Research Council Centre of Excellence for Translational Photosynthesis, Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT, Australia
| |
Collapse
|
16
|
Miguel VN, Manavella PA, Chan RL, Capella MA. The AtHB1 Transcription Factor Controls the miR164-CUC2 Regulatory Node to Modulate Leaf Development. PLANT & CELL PHYSIOLOGY 2020; 61:659-670. [PMID: 31868910 DOI: 10.1093/pcp/pcz233] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 12/13/2019] [Indexed: 06/10/2023]
Abstract
The presence of small tooth-like indentations, or serrations, characterizes leaf margins of Arabidopsis thaliana plants. The NAC family member CUP-SHAPED COTYLEDON 2 (CUC2), which undergoes post-transcriptional gene silencing by three micro-RNA genes (MIR164A, B and C), controls the extension of leaf serration. Here, we analyzed the role of AtHB1, a transcription factor (TF) belonging to the homeodomain-leucine zipper subfamily I, in shaping leaf margins. Using mutants with an impaired silencing pathway as background, we obtained transgenic plants expressing AtHB1 over 100 times compared to controls. These plants presented an atypical developmental phenotype characterized by leaves with deep serration. Transcript measurements revealed that CUC2 expression was induced in plants overexpressing AtHB1 and repressed in athb1 mutants, indicating a positive regulation exerted by this TF. Moreover, molecular analyses of AtHB1 overexpressing and mutant plants revealed that AtHB1 represses MIR164 transcription. We found that overexpression of MIR164B was able to reverse the serration phenotype of plants overexpressing AtHB1. Finally, chromatin immunoprecipitation assays revealed that AtHB1 was able to bind in vivo the promoter regions of all three MIR164 encoding loci. Altogether, our results indicate that AtHB1 directly represses MIR164 expression to enhance leaf serration by increasing CUC2 levels.
Collapse
Affiliation(s)
- Virginia N Miguel
- Instituto de Agrobiotecnolog�a del Litoral, Facultad de Bioqu�mica y Ciencias Biol�gicas, Universidad Nacional del Litoral - CONICET, Colectora Ruta Nacional 168 km 0, Santa Fe, Argentina
| | - Pablo A Manavella
- Instituto de Agrobiotecnolog�a del Litoral, Facultad de Bioqu�mica y Ciencias Biol�gicas, Universidad Nacional del Litoral - CONICET, Colectora Ruta Nacional 168 km 0, Santa Fe, Argentina
| | - Raquel L Chan
- Instituto de Agrobiotecnolog�a del Litoral, Facultad de Bioqu�mica y Ciencias Biol�gicas, Universidad Nacional del Litoral - CONICET, Colectora Ruta Nacional 168 km 0, Santa Fe, Argentina
| | - Matï As Capella
- Instituto de Agrobiotecnolog�a del Litoral, Facultad de Bioqu�mica y Ciencias Biol�gicas, Universidad Nacional del Litoral - CONICET, Colectora Ruta Nacional 168 km 0, Santa Fe, Argentina
| |
Collapse
|
17
|
Liew LC, Narsai R, Wang Y, Berkowitz O, Whelan J, Lewsey MG. Temporal tissue-specific regulation of transcriptomes during barley (Hordeum vulgare) seed germination. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:700-715. [PMID: 31628689 DOI: 10.1111/tpj.14574] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 09/09/2019] [Accepted: 10/08/2019] [Indexed: 06/10/2023]
Abstract
The distinct functions of individual cell types require cells to express specific sets of genes. The germinating seed is an excellent model to study genome regulation between cell types since the majority of the transcriptome is differentially expressed in a short period, beginning from a uniform, metabolically inactive state. In this study, we applied laser-capture microdissection RNA-sequencing to small numbers of cells from the plumule, radicle tip and scutellum of germinating barley seeds every 8 h, over a 48 h time course. Tissue-specific gene expression was notably common; 25% (910) of differentially expressed transcripts in plumule, 34% (1876) in radicle tip and 41% (2562) in scutellum were exclusive to that organ. We also determined that tissue-specific storage of transcripts occurs during seed development and maturation. Co-expression of genes had strong spatiotemporal structure, with most co-expression occurring within one organ and at a subset of specific time points during germination. Overlapping and distinct enrichment of functional categories were observed in the tissue-specific profiles. We identified candidate transcription factors amongst these that may be regulators of spatiotemporal gene expression programs. Our findings contribute to the broader goal of generating an integrative model that describes the structure and function of individual cells within seeds during germination.
Collapse
Affiliation(s)
- Lim Chee Liew
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
- Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, Bundoora, Vic., 3086, Australia
| | - Reena Narsai
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
- Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, Bundoora, Vic., 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
| | - Yan Wang
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
- Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, Bundoora, Vic., 3086, Australia
| | - Oliver Berkowitz
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
- Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, Bundoora, Vic., 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
| | - James Whelan
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
- Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, Bundoora, Vic., 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
| | - Mathew G Lewsey
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, Vic., 3086, Australia
| |
Collapse
|
18
|
Zhu Q, Gallemí M, Pospíšil J, Žádníková P, Strnad M, Benková E. Root gravity response module guides differential growth determining both root bending and apical hook formation in Arabidopsis. Development 2019; 146:dev.175919. [PMID: 31391194 DOI: 10.1242/dev.175919] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 07/23/2019] [Indexed: 12/11/2022]
Abstract
The apical hook is a transiently formed structure that plays a protective role when the germinating seedling penetrates through the soil towards the surface. Crucial for proper bending is the local auxin maxima, which defines the concave (inner) side of the hook curvature. As no sign of asymmetric auxin distribution has been reported in embryonic hypocotyls prior to hook formation, the question of how auxin asymmetry is established in the early phases of seedling germination remains largely unanswered. Here, we analyzed the auxin distribution and expression of PIN auxin efflux carriers from early phases of germination, and show that bending of the root in response to gravity is the crucial initial cue that governs the hypocotyl bending required for apical hook formation. Importantly, polar auxin transport machinery is established gradually after germination starts as a result of tight root-hypocotyl interaction and a proper balance between abscisic acid and gibberellins.This article has an associated 'The people behind the papers' interview.
Collapse
Affiliation(s)
- Qiang Zhu
- Basic Forestry & Proteomics Center (BFPC), College of Forestry, Fujian Agriculture and Forestry University, 350002 Fuzhou, China.,Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria
| | - Marçal Gallemí
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria
| | - Jiří Pospíšil
- Laboratory of Growth Regulators, Institute of Experimental Botany ASCR & Palacký University Olomouc, CZ-771 47, Czech Republic
| | - Petra Žádníková
- Department of Plant Systems Biology, VIB, 9052 Gent, Belgium
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Institute of Experimental Botany ASCR & Palacký University Olomouc, CZ-771 47, Czech Republic
| | - Eva Benková
- Institute of Science and Technology Austria, Klosterneuburg, 3400, Austria
| |
Collapse
|
19
|
Footitt S, Clewes R, Feeney M, Finch‐Savage WE, Frigerio L. Aquaporins influence seed dormancy and germination in response to stress. PLANT, CELL & ENVIRONMENT 2019; 42:2325-2339. [PMID: 30986891 PMCID: PMC6767449 DOI: 10.1111/pce.13561] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 04/09/2019] [Indexed: 05/10/2023]
Abstract
Aquaporins influence water flow in plants, yet little is known of their involvement in the water-driven process of seed germination. We therefore investigated their role in seeds in the laboratory and under field and global warming conditions. We mapped the expression of tonoplast intrinsic proteins (TIPs) during dormancy cycling and during germination under normal and water stress conditions. We found that the two key tonoplast aquaporins, TIP3;1 and TIP3;2, which have previously been implicated in water or solute transport, respectively, act antagonistically to modulate the response to abscisic acid, with TIP3;1 being a positive and TIP3;2 a negative regulator. A third isoform, TIP4;1, which is normally expressed upon completion of germination, was found to play an earlier role during water stress. Seed TIPs also contribute to the regulation of depth of primary dormancy and differences in the induction of secondary dormancy during dormancy cycling. Protein and gene expression during annual cycling under field conditions and a global warming scenario further illustrate this role. We propose that the different responses of the seed TIP contribute to mechanisms that influence dormancy status and the timing of germination under variable soil conditions.
Collapse
Affiliation(s)
- Steven Footitt
- School of Life SciencesUniversity of WarwickWarwickshireCV4 7ALUK
| | - Rachel Clewes
- School of Life SciencesUniversity of WarwickWarwickshireCV4 7ALUK
| | - Mistianne Feeney
- School of Life SciencesUniversity of WarwickWarwickshireCV4 7ALUK
| | | | - Lorenzo Frigerio
- School of Life SciencesUniversity of WarwickWarwickshireCV4 7ALUK
| |
Collapse
|
20
|
Ravindran P, Kumar PP. Regulation of Seed Germination: The Involvement of Multiple Forces Exerted via Gibberellic Acid Signaling. MOLECULAR PLANT 2019; 12:24-26. [PMID: 30582998 DOI: 10.1016/j.molp.2018.12.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 12/10/2018] [Accepted: 12/17/2018] [Indexed: 05/18/2023]
Affiliation(s)
- Pratibha Ravindran
- Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Prakash P Kumar
- Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.
| |
Collapse
|
21
|
Sánchez-Montesino R, Bouza-Morcillo L, Marquez J, Ghita M, Duran-Nebreda S, Gómez L, Holdsworth MJ, Bassel G, Oñate-Sánchez L. A Regulatory Module Controlling GA-Mediated Endosperm Cell Expansion Is Critical for Seed Germination in Arabidopsis. MOLECULAR PLANT 2019; 12:71-85. [PMID: 30419294 PMCID: PMC7086157 DOI: 10.1016/j.molp.2018.10.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/30/2018] [Accepted: 10/31/2018] [Indexed: 05/19/2023]
Abstract
A key component of seed germination is the interplay of mechanical forces governing embryo growth and the surrounding restraining endosperm tissue. Endosperm cell separation is therefore thought to play a critical role in the control of this developmental transition. Here we demonstrate that in Arabidopsis thaliana seeds, endosperm cell expansion is a key component of germination. Endosperm cells expand to accommodate embryo growth prior to germination. We show that this is an actively regulated process supported by spatiotemporal control of the cell expansion gene EXPANSIN 2 (EXPA2). The NAC transcription factors NAC25 and NAC1L were identified as upstream regulators of EXPA2 expression, gibberellin-mediated endosperm expansion, and seed germination. The DELLA protein RGL2 repressed activation of the EXPA2 promoter by NAC25/NAC1L. Taken together, our findings uncover a key role of the GA/DELLA-NAC25/NAC1L-EXPA2 network in regulating endosperm cell expansion to control the seed-to-seedling transition.
Collapse
Affiliation(s)
- Rocío Sánchez-Montesino
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, Pozuelo de Alarcón, Madrid 28223, Spain
| | - Laura Bouza-Morcillo
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, Pozuelo de Alarcón, Madrid 28223, Spain
| | - Julietta Marquez
- School of Biosciences, University of Nottingham, Loughborough LE12 5RD, UK
| | - Melania Ghita
- School of Biosciences, University of Nottingham, Loughborough LE12 5RD, UK
| | | | - Luis Gómez
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, Pozuelo de Alarcón, Madrid 28223, Spain; Departamento de Sistemas y Recursos Naturales, E.T.S.I. Montes, Forestal y del Medio Natural, Campus de Moncloa, 28040 Madrid, Spain
| | | | - George Bassel
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK.
| | - Luis Oñate-Sánchez
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, Pozuelo de Alarcón, Madrid 28223, Spain.
| |
Collapse
|
22
|
Sessa G, Carabelli M, Possenti M, Morelli G, Ruberti I. Multiple Links between HD-Zip Proteins and Hormone Networks. Int J Mol Sci 2018; 19:ijms19124047. [PMID: 30558150 PMCID: PMC6320839 DOI: 10.3390/ijms19124047] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/06/2018] [Accepted: 12/12/2018] [Indexed: 01/01/2023] Open
Abstract
HD-Zip proteins are unique to plants, and contain a homeodomain closely linked to a leucine zipper motif, which are involved in dimerization and DNA binding. Based on homology in the HD-Zip domain, gene structure and the presence of additional motifs, HD-Zips are divided into four families, HD-Zip I–IV. Phylogenetic analysis of HD-Zip genes using transcriptomic and genomic datasets from a wide range of plant species indicate that the HD-Zip protein class was already present in green algae. Later, HD-Zips experienced multiple duplication events that promoted neo- and sub-functionalizations. HD-Zip proteins are known to control key developmental and environmental responses, and a growing body of evidence indicates a strict link between members of the HD-Zip II and III families and the auxin machineries. Interactions of HD-Zip proteins with other hormones such as brassinolide and cytokinin have also been described. More recent data indicate that members of different HD-Zip families are directly involved in the regulation of abscisic acid (ABA) homeostasis and signaling. Considering the fundamental role of specific HD-Zip proteins in the control of key developmental pathways and in the cross-talk between auxin and cytokinin, a relevant role of these factors in adjusting plant growth and development to changing environment is emerging.
Collapse
Affiliation(s)
- Giovanna Sessa
- Institute of Molecular Biology and Pathology, National Research Council, P.le A. Moro 5, 00185 Rome, Italy.
| | - Monica Carabelli
- Institute of Molecular Biology and Pathology, National Research Council, P.le A. Moro 5, 00185 Rome, Italy.
| | - Marco Possenti
- Research Centre for Genomics and Bioinformatics, Council for Agricultural Research and Economics (CREA), Via Ardeatina 546, 00178 Rome, Italy.
| | - Giorgio Morelli
- Research Centre for Genomics and Bioinformatics, Council for Agricultural Research and Economics (CREA), Via Ardeatina 546, 00178 Rome, Italy.
| | - Ida Ruberti
- Institute of Molecular Biology and Pathology, National Research Council, P.le A. Moro 5, 00185 Rome, Italy.
| |
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
|
Van De Velde K, Ruelens P, Geuten K, Rohde A, Van Der Straeten D. Exploiting DELLA Signaling in Cereals. TRENDS IN PLANT SCIENCE 2017; 22:880-893. [PMID: 28843766 DOI: 10.1016/j.tplants.2017.07.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/13/2017] [Accepted: 07/29/2017] [Indexed: 05/04/2023]
Abstract
The spectacular yield increases in rice and wheat during the green revolution were partly realized by reduced gibberellin (GA) synthesis or sensitivity, both causing the accumulation of DELLA proteins. Although insights into the regulation of plant growth and development by DELLA proteins advanced rapidly in arabidopsis (Arabidopsis thaliana), DELLA-mediated regulation of downstream responses in cereals has received little attention to date. Furthermore, translating this research from arabidopsis to cereals is challenging given their different growth patterns and our phylogenetic analysis which reveals that DELLA-related DGLLA proteins exist in cereals but not in arabidopsis. Therefore, understanding the molecular basis of DELLA function in cereals holds great potential to improve yield. In this review, we propose to extend the focus of DELLA functional research to cereals, and highlight the appropriate tools that are now available to achieve this.
Collapse
Affiliation(s)
- Karel Van De Velde
- R&D Innovation Center, Bayer CropScience, Technologiepark 38, Ghent, Belgium; Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckstraat 35, Ghent, Belgium
| | - Philip Ruelens
- Laboratory of Molecular Plant Biology, Department of Biology, KU Leuven, Kasteelpark Arenberg 31, Heverlee, Belgium
| | - Koen Geuten
- Laboratory of Molecular Plant Biology, Department of Biology, KU Leuven, Kasteelpark Arenberg 31, Heverlee, Belgium
| | - Antje Rohde
- R&D Innovation Center, Bayer CropScience, Technologiepark 38, Ghent, Belgium; Equal contributions
| | - Dominique Van Der Straeten
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckstraat 35, Ghent, Belgium; Equal contributions; ORCID ID 0000-0002-7755-1420.
| |
Collapse
|
25
|
Li Q, Li L, Liu Y, Lv Q, Zhang H, Zhu J, Li X. Influence of TaGW2-6A on seed development in wheat by negatively regulating gibberellin synthesis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2017; 263:226-235. [PMID: 28818379 DOI: 10.1016/j.plantsci.2017.07.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/26/2017] [Accepted: 07/30/2017] [Indexed: 05/09/2023]
Abstract
Gibberellins (GA) are involved in seed development and E3 ubiquitin-ligases actively participate in GA perception and signal transduction. TaGW2-6A encodes a RING E3 ubiquitin-ligase that negatively regulates grain size. Therefore, Chinese Spring (CS) and its TaGW2-6A allelic variants (NIL31) were investigated to elucidate the relative contribution of GA to the regulation of seed development in wheat. The expression levels of GA biosynthesis and response genes were higher in NIL31 than CS, especially those of GA 3-oxidase and GASA4. The expression of TaGW2-6A exhibited the opposite pattern compared with those of the GA biosynthesis and response genes in CS and NIL31. The results showed that the GA content of NIL31 was significantly higher than that of CS. Thus, TaGW2-6A had a negative relationship on GA synthesis and response genes. Moreover, after GA treatment, CS and NIL31 exhibited the opposite phenotypes and GA contents. These results demonstrate that allelic variation in TaGW2-6A increases the seed size via the GA hormone pathway. Transcriptional analysis and cytological analysis showed that TaGW2-6A allelic variants regulated GA synthesis via GA 3-oxidases, thereby leading to the higher expression of GASA4 to control endosperm cell elongation and division during grain filling. Finally, germination experiments were performed to elucidate the relationships between TaGW2-6A and GA synthesis and response genes in wheat with full fertility. These results provide new insights into the effects of the ubiquitination system mediated by TaGW2-6A on the GA hormone signaling pathway, thereby improving our understanding of the role of TaGW2-6A in seed development in wheat.
Collapse
Affiliation(s)
- Qingyan Li
- State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Liqun Li
- State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Yan Liu
- State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Qian Lv
- State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Heng Zhang
- State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Jian Zhu
- State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Xuejun Li
- State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China.
| |
Collapse
|
26
|
Narsai R, Gouil Q, Secco D, Srivastava A, Karpievitch YV, Liew LC, Lister R, Lewsey MG, Whelan J. Extensive transcriptomic and epigenomic remodelling occurs during Arabidopsis thaliana germination. Genome Biol 2017; 18:172. [PMID: 28911330 PMCID: PMC5599894 DOI: 10.1186/s13059-017-1302-3] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Accepted: 08/16/2017] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Seed germination involves progression from complete metabolic dormancy to a highly active, growing seedling. Many factors regulate germination and these interact extensively, forming a complex network of inputs that control the seed-to-seedling transition. Our understanding of the direct regulation of gene expression and the dynamic changes in the epigenome and small RNAs during germination is limited. The interactions between genome, transcriptome and epigenome must be revealed in order to identify the regulatory mechanisms that control seed germination. RESULTS We present an integrated analysis of high-resolution RNA sequencing, small RNA sequencing and MethylC sequencing over ten developmental time points in Arabidopsis thaliana seeds, finding extensive transcriptomic and epigenomic transformations associated with seed germination. We identify previously unannotated loci from which messenger RNAs are expressed transiently during germination and find widespread alternative splicing and divergent isoform abundance of genes involved in RNA processing and splicing. We generate the first dynamic transcription factor network model of germination, identifying known and novel regulatory factors. Expression of both microRNA and short interfering RNA loci changes significantly during germination, particularly between the seed and the post-germinative seedling. These are associated with changes in gene expression and large-scale demethylation observed towards the end of germination, as the epigenome transitions from an embryo-like to a vegetative seedling state. CONCLUSIONS This study reveals the complex dynamics and interactions of the transcriptome and epigenome during seed germination, including the extensive remodelling of the seed DNA methylome from an embryo-like to vegetative-like state during the seed-to-seedling transition. Data are available for exploration in a user-friendly browser at https://jbrowse.latrobe.edu.au/germination_epigenome .
Collapse
Affiliation(s)
- Reena Narsai
- ARC Centre of Excellence in Plant Energy Biology, Department of Animal, Plant and Soil Sciences, School of Life Sciences, La Trobe University, Melbourne, VIC, 3086, Australia.
- Centre for AgriBioscience, Department of Animal, Plant and Soil Sciences, School of Life Sciences, La Trobe University, Melbourne, VIC, 3086, Australia.
| | - Quentin Gouil
- Centre for AgriBioscience, Department of Animal, Plant and Soil Sciences, School of Life Sciences, La Trobe University, Melbourne, VIC, 3086, Australia
| | - David Secco
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, 6009, Australia
| | - Akanksha Srivastava
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, 6009, Australia
| | - Yuliya V Karpievitch
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, 6009, Australia
- Harry Perkins Institute of Medical Research, Perth, WA, 6009, Australia
| | - Lim Chee Liew
- Centre for AgriBioscience, Department of Animal, Plant and Soil Sciences, School of Life Sciences, La Trobe University, Melbourne, VIC, 3086, Australia
| | - Ryan Lister
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, 6009, Australia
- Harry Perkins Institute of Medical Research, Perth, WA, 6009, Australia
| | - Mathew G Lewsey
- Centre for AgriBioscience, Department of Animal, Plant and Soil Sciences, School of Life Sciences, La Trobe University, Melbourne, VIC, 3086, Australia.
| | - James Whelan
- ARC Centre of Excellence in Plant Energy Biology, Department of Animal, Plant and Soil Sciences, School of Life Sciences, La Trobe University, Melbourne, VIC, 3086, Australia
| |
Collapse
|
27
|
Temperature variability is integrated by a spatially embedded decision-making center to break dormancy in Arabidopsis seeds. Proc Natl Acad Sci U S A 2017; 114:6629-6634. [PMID: 28584126 DOI: 10.1073/pnas.1704745114] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Plants perceive and integrate information from the environment to time critical transitions in their life cycle. Some mechanisms underlying this quantitative signal processing have been described, whereas others await discovery. Seeds have evolved a mechanism to integrate environmental information by regulating the abundance of the antagonistically acting hormones abscisic acid (ABA) and gibberellin (GA). Here, we show that hormone metabolic interactions and their feedbacks are sufficient to create a bistable developmental fate switch in Arabidopsis seeds. A digital single-cell atlas mapping the distribution of hormone metabolic and response components revealed their enrichment within the embryonic radicle, identifying the presence of a decision-making center within dormant seeds. The responses to both GA and ABA were found to occur within distinct cell types, suggesting cross-talk occurs at the level of hormone transport between these signaling centers. We describe theoretically, and demonstrate experimentally, that this spatial separation within the decision-making center is required to process variable temperature inputs from the environment to promote the breaking of dormancy. In contrast to other noise-filtering systems, including human neurons, the functional role of this spatial embedding is to leverage variability in temperature to transduce a fate-switching signal within this biological system. Fluctuating inputs therefore act as an instructive signal for seeds, enhancing the accuracy with which plants are established in ecosystems, and distributed computation within the radicle underlies this signal integration mechanism.
Collapse
|