1
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Pozzi CM, Brambilla VF, Gaiti A, Spada A. Plant developmental oddities. PLANTA 2024; 260:104. [PMID: 39316298 PMCID: PMC11422487 DOI: 10.1007/s00425-024-04534-8] [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: 04/22/2024] [Accepted: 09/15/2024] [Indexed: 09/25/2024]
Abstract
MAIN CONCLUSION Plants lacking shoot apical meristem develop with unique body shapes, suggesting rewiring of developmental genes. This loss of the meristem is likely influenced by a combination of environmental factors and evolutionary pressures. This study explores the development of plant bodies in three families (Podostemaceae, Lemnaceae, and Gesneriaceae) where the shoot apical meristem (SAM), a key structure for growth, is absent or altered. The review highlights alternative developmental strategies these plants employ. Also, we considered alternative reproduction in those species, namely through structures like turions, fronds, or modified leaves, bypassing the need for a SAM. Further, we report on studies based on the expression patterns of genes known to be involved in SAM formation and function. Interestingly, these genes are still present but expressed in atypical locations, suggesting a rewiring of developmental networks. Our view on the current literature and knowledge indicates that the loss or reduction of the SAM is driven by a combination of environmental pressures and evolutionary constraints, leading to these unique morphologies. Further research, also building on Next-Generation Sequencing, will be instrumental to explore the genetic basis for these adaptations and how environmental factors influence them.
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Affiliation(s)
- Carlo M Pozzi
- Department of Agricultural and Environmental Sciences, University of Milan, Via Celoria 2, 20133, Milan, Italy
| | - Vittoria F Brambilla
- Department of Agricultural and Environmental Sciences, University of Milan, Via Celoria 2, 20133, Milan, Italy
| | - Angelo Gaiti
- Department of Agricultural and Environmental Sciences, University of Milan, Via Celoria 2, 20133, Milan, Italy
| | - Alberto Spada
- Department of Agricultural and Environmental Sciences, University of Milan, Via Celoria 2, 20133, Milan, Italy.
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2
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Rodriguez K, Kao L, Cerbantez-Bueno VE, Delgadillo C, Nguyen D, Ullah S, Delgadillo C, Reddy GV. HAIRY MERISTEM proteins regulate the WUSCHEL protein levels in mediating CLAVATA3 expression. PHYSIOLOGIA PLANTARUM 2024; 176:e14505. [PMID: 39221514 DOI: 10.1111/ppl.14505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 07/30/2024] [Accepted: 08/08/2024] [Indexed: 09/04/2024]
Abstract
The precise regulation of stem cells in the shoot apical meristems (SAMs) involves the function of the homeodomain transcription factor (TF)-WUSCHEL (WUS). WUS has been shown to move from the site of production-the rib-meristem (RM), into overlaying cells of the central zone (CZ), where it specifies stem cells and also regulates the transcription of CLAVATA3 (CLV3). The secreted signalling peptide CLV3 activates a receptor kinase signalling that restricts WUS transcription and also regulates the nuclear gradient of WUS by offsetting nuclear export. WUS has been shown to regulate both CLV3 levels and spatial activation, restricting its expression to a few cells in the CZ. The HAIRY MERISTEM (HAM), a GRASS-domain class of TFs expressed in the RM, has been shown to physically interact with WUS and regulate CLV3 expression. However, the mechanisms by which this interaction regulates CLV3 expression non-cell autonomously remain unclear. Here, we show that HAM function is required for regulating the WUS protein stability, and the CLV3 expression responds to altered WUS protein levels in ham mutants. Thus, HAM proteins non-cell autonomously regulates CLV3 expression.
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Affiliation(s)
- Kevin Rodriguez
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA, USA
| | - Lloyd Kao
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA, USA
| | | | - Christian Delgadillo
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA, USA
| | - Dorothy Nguyen
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA, USA
| | - Samin Ullah
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA, USA
| | - Cameron Delgadillo
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA, USA
| | - G Venugopala Reddy
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA, USA
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3
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Demesa-Arevalo E, Narasimhan M, Simon R. Intercellular Communication in Shoot Meristems. ANNUAL REVIEW OF PLANT BIOLOGY 2024; 75:319-344. [PMID: 38424066 DOI: 10.1146/annurev-arplant-070523-035342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
The shoot meristem of land plants maintains the capacity for organ generation throughout its lifespan due to a group of undifferentiated stem cells. Most meristems are shaped like a dome with a precise spatial arrangement of functional domains, and, within and between these domains, cells interact through a network of interconnected signaling pathways. Intercellular communication in meristems is mediated by mobile transcription factors, small RNAs, hormones, and secreted peptides that are perceived by membrane-localized receptors. In recent years, we have gained deeper insight into the underlying molecular processes of the shoot meristem, and we discuss here how plants integrate internal and external inputs to control shoot meristem activities.
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Affiliation(s)
- Edgar Demesa-Arevalo
- Institute for Developmental Genetics, Heinrich Heine University, Düsseldorf, Germany;
| | - Madhumitha Narasimhan
- Institute for Developmental Genetics, Heinrich Heine University, Düsseldorf, Germany;
| | - Rüdiger Simon
- Institute for Developmental Genetics, Heinrich Heine University, Düsseldorf, Germany;
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4
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Cui G, Li Y, Zheng L, Smith C, Bevan MW, Li Y. The peptidase DA1 cleaves and destabilizes WUSCHEL to control shoot apical meristem size. Nat Commun 2024; 15:4627. [PMID: 38821962 PMCID: PMC11143343 DOI: 10.1038/s41467-024-48361-7] [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: 02/20/2023] [Accepted: 04/29/2024] [Indexed: 06/02/2024] Open
Abstract
Stem cells in plants and animals are the source of new tissues and organs. In plants, stem cells are maintained in the central zone (CZ) of multicellular meristems, and large shoot meristems with an increased stem cell population hold promise for enhancing yield. The mobile homeodomain transcription factor WUSCHEL (WUS) is a central regulator of stem cell function in plant shoot meristems. Despite its central importance, the factors that directly modulate WUS protein stability have been a long-standing question. Here, we show that the peptidase DA1 physically interacts with and cleaves the WUS protein, leading to its destabilization. Furthermore, our results reveal that cytokinin signaling represses the level of DA1 protein in the shoot apical meristem, thereby increasing the accumulation of WUS protein. Consistent with these observations, loss of DA1 function results in larger shoot apical meristems with an increased stem cell population and also influences cytokinin-induced enlargement of shoot apical meristem. Collectively, our findings uncover a previously unrecognized mechanism by which the repression of DA1 by cytokinin signaling stabilizes WUS, resulting in the enlarged shoot apical meristems with the increased stem cell number during plant growth and development.
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Affiliation(s)
- Guicai Cui
- Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- College of Advanced Agriculture, University of Chinese Academy of Sciences, Beijing, China
| | - Yu Li
- Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Leiying Zheng
- College of Advanced Agriculture, University of Chinese Academy of Sciences, Beijing, China.
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
| | | | | | - Yunhai Li
- Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
- College of Advanced Agriculture, University of Chinese Academy of Sciences, Beijing, China.
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5
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Kuznetsova K, Efremova E, Dodueva I, Lebedeva M, Lutova L. Functional Modules in the Meristems: "Tinkering" in Action. PLANTS (BASEL, SWITZERLAND) 2023; 12:3661. [PMID: 37896124 PMCID: PMC10610496 DOI: 10.3390/plants12203661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/13/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023]
Abstract
BACKGROUND A feature of higher plants is the modular principle of body organisation. One of these conservative morphological modules that regulate plant growth, histogenesis and organogenesis is meristems-structures that contain pools of stem cells and are generally organised according to a common principle. Basic content: The development of meristems is under the regulation of molecular modules that contain conservative interacting components and modulate the expression of target genes depending on the developmental context. In this review, we focus on two molecular modules that act in different types of meristems. The WOX-CLAVATA module, which includes the peptide ligand, its receptor and the target transcription factor, is responsible for the formation and control of the activity of all meristem types studied, but it has its own peculiarities in different meristems. Another regulatory module is the so-called florigen-activated complex, which is responsible for the phase transition in the shoot vegetative meristem (e.g., from the vegetative shoot apical meristem to the inflorescence meristem). CONCLUSIONS The review considers the composition and functions of these two functional modules in different developmental programmes, as well as their appearance, evolution and use in plant breeding.
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Affiliation(s)
| | | | - Irina Dodueva
- Department of Genetics and Biotechnology, Saint Petersburg State University, Universitetskaya Emb. 7/9, 199034 Saint Petersburg, Russia; (K.K.); (E.E.); (M.L.); (L.L.)
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6
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Hong L, Fletcher JC. Stem Cells: Engines of Plant Growth and Development. Int J Mol Sci 2023; 24:14889. [PMID: 37834339 PMCID: PMC10573764 DOI: 10.3390/ijms241914889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 09/30/2023] [Accepted: 10/03/2023] [Indexed: 10/15/2023] Open
Abstract
The development of both animals and plants relies on populations of pluripotent stem cells that provide the cellular raw materials for organ and tissue formation. Plant stem cell reservoirs are housed at the shoot and root tips in structures called meristems, with the shoot apical meristem (SAM) continuously producing aerial leaf, stem, and flower organs throughout the life cycle. Thus, the SAM acts as the engine of plant development and has unique structural and molecular features that allow it to balance self-renewal with differentiation and act as a constant source of new cells for organogenesis while simultaneously maintaining a stem cell reservoir for future organ formation. Studies have identified key roles for intercellular regulatory networks that establish and maintain meristem activity, including the KNOX transcription factor pathway and the CLV-WUS stem cell feedback loop. In addition, the plant hormones cytokinin and auxin act through their downstream signaling pathways in the SAM to integrate stem cell activity and organ initiation. This review discusses how the various regulatory pathways collectively orchestrate SAM function and touches on how their manipulation can alter stem cell activity to improve crop yield.
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Affiliation(s)
- Liu Hong
- Plant Gene Expression Center, United States Department of Agriculture—Agricultural Research Service, Albany, CA 94710, USA;
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Jennifer C. Fletcher
- Plant Gene Expression Center, United States Department of Agriculture—Agricultural Research Service, Albany, CA 94710, USA;
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA 94720, USA
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7
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Wang Y, Jiao Y. Cell signaling in the shoot apical meristem. PLANT PHYSIOLOGY 2023; 193:70-82. [PMID: 37224874 DOI: 10.1093/plphys/kiad309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 04/24/2023] [Accepted: 05/10/2023] [Indexed: 05/26/2023]
Abstract
Distinct from animals, plants maintain organogenesis from specialized tissues termed meristems throughout life. In the shoot apex, the shoot apical meristem (SAM) produces all aerial organs, such as leaves, from its periphery. For this, the SAM needs to precisely balance stem cell renewal and differentiation, which is achieved through dynamic zonation of the SAM, and cell signaling within functional domains is key for SAM functions. The WUSCHEL-CLAVATA feedback loop plays a key role in SAM homeostasis, and recent studies have uncovered new components, expanding our understanding of the spatial expression and signaling mechanism. Advances in polar auxin transport and signaling have contributed to knowledge of the multifaceted roles of auxin in the SAM and organogenesis. Finally, single-cell techniques have expanded our understanding of the cellular functions within the shoot apex at single-cell resolution. In this review, we summarize the most up-to-date understanding of cell signaling in the SAM and focus on the multiple levels of regulation of SAM formation and maintenance.
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Affiliation(s)
- Ying Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuling Jiao
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agricultural Sciences in Weifang, Weifang, Shandong 261325, China
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8
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Šmeringai J, Schrumpfová PP, Pernisová M. Cytokinins - regulators of de novo shoot organogenesis. FRONTIERS IN PLANT SCIENCE 2023; 14:1239133. [PMID: 37662179 PMCID: PMC10471832 DOI: 10.3389/fpls.2023.1239133] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 07/31/2023] [Indexed: 09/05/2023]
Abstract
Plants, unlike animals, possess a unique developmental plasticity, that allows them to adapt to changing environmental conditions. A fundamental aspect of this plasticity is their ability to undergo postembryonic de novo organogenesis. This requires the presence of regulators that trigger and mediate specific spatiotemporal changes in developmental programs. The phytohormone cytokinin has been known as a principal regulator of plant development for more than six decades. In de novo shoot organogenesis and in vitro shoot regeneration, cytokinins are the prime candidates for the signal that determines shoot identity. Both processes of de novo shoot apical meristem development are accompanied by changes in gene expression, cell fate reprogramming, and the switching-on of the shoot-specific homeodomain regulator, WUSCHEL. Current understanding about the role of cytokinins in the shoot regeneration will be discussed.
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Affiliation(s)
- Ján Šmeringai
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Petra Procházková Schrumpfová
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Markéta Pernisová
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Brno, Czechia
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9
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Wang Q, Xue N, Sun C, Tao J, Mi C, Yuan Y, Pan X, Gui M, Long R, Ding R, Li S, Lin L. Transcriptomic Profiling of Shoot Apical Meristem Aberrations in the Multi-Main-Stem Mutant ( ms) of Brassica napus L. Genes (Basel) 2023; 14:1396. [PMID: 37510301 PMCID: PMC10378962 DOI: 10.3390/genes14071396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/16/2023] [Accepted: 06/30/2023] [Indexed: 07/30/2023] Open
Abstract
Rapeseed (Brassica napus L.) is a globally important oilseed crop with various uses, including the consumption of its succulent stems as a seasonal vegetable, but its uniaxial branching habit limits the stem yield. Therefore, developing a multi-stem rapeseed variety has become increasingly crucial. In this study, a natural mutant of the wild type (ZY511, Zhongyou511) with stable inheritance of the multi-stem trait (ms) was obtained, and it showed abnormal shoot apical meristem (SAM) development and an increased main stem number compared to the WT. Histological and scanning electron microscopy analyses revealed multiple SAMs in the ms mutant, whereas only a single SAM was found in the WT. Transcriptome analyses showed significant alterations in the expression of genes involved in cytokinin (CK) biosynthesis and metabolism pathways in the ms mutant. These findings provide insight into the mechanism of multi-main-stem formation in Brassica napus L. and lay a theoretical foundation for breeding multi-main-stem rapeseed vegetable varieties.
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Affiliation(s)
- Qian Wang
- College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming 650201, China
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650200, China
- Engineering Research Center of Vegetable Germplasm Innovation and Support Production Technology, Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, 2238 Beijing Road, Kunming 650205, China
| | - Na Xue
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650200, China
- Engineering Research Center of Vegetable Germplasm Innovation and Support Production Technology, Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, 2238 Beijing Road, Kunming 650205, China
| | - Chao Sun
- Tea Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650221, China
| | - Jing Tao
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650200, China
- Engineering Research Center of Vegetable Germplasm Innovation and Support Production Technology, Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, 2238 Beijing Road, Kunming 650205, China
| | - Chao Mi
- College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming 650201, China
| | - Yi Yuan
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650200, China
- Engineering Research Center of Vegetable Germplasm Innovation and Support Production Technology, Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, 2238 Beijing Road, Kunming 650205, China
| | - Xiangwei Pan
- College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming 650201, China
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650200, China
| | - Min Gui
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650200, China
- Engineering Research Center of Vegetable Germplasm Innovation and Support Production Technology, Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, 2238 Beijing Road, Kunming 650205, China
| | - Ronghua Long
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650200, China
- Engineering Research Center of Vegetable Germplasm Innovation and Support Production Technology, Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, 2238 Beijing Road, Kunming 650205, China
| | - Renzhan Ding
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650200, China
| | - Shikai Li
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650200, China
- Engineering Research Center of Vegetable Germplasm Innovation and Support Production Technology, Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, 2238 Beijing Road, Kunming 650205, China
| | - Liangbin Lin
- College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming 650201, China
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10
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Sierra J, Escobar-Tovar L, Leon P. Plastids: diving into their diversity, their functions, and their role in plant development. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:2508-2526. [PMID: 36738278 DOI: 10.1093/jxb/erad044] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 01/31/2023] [Indexed: 06/06/2023]
Abstract
Plastids are a group of essential, heterogenous semi-autonomous organelles characteristic of plants that perform photosynthesis and a diversity of metabolic pathways that impact growth and development. Plastids are remarkably dynamic and can interconvert in response to specific developmental and environmental cues, functioning as a central metabolic hub in plant cells. By far the best studied plastid is the chloroplast, but in recent years the combination of modern techniques and genetic analyses has expanded our current understanding of plastid morphological and functional diversity in both model and non-model plants. These studies have provided evidence of an unexpected diversity of plastid subtypes with specific characteristics. In this review, we describe recent findings that provide insights into the characteristics of these specialized plastids and their functions. We concentrate on the emerging evidence that supports the model that signals derived from particular plastid types play pivotal roles in plant development, environmental, and defense responses. Furthermore, we provide examples of how new technologies are illuminating the functions of these specialized plastids and the overall complexity of their differentiation processes. Finally, we discuss future research directions such as the use of ectopic plastid differentiation as a valuable tool to characterize factors involved in plastid differentiation. Collectively, we highlight important advances in the field that can also impact future agricultural and biotechnological improvement in plants.
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Affiliation(s)
- Julio Sierra
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca 62210, México
| | - Lina Escobar-Tovar
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca 62210, México
| | - Patricia Leon
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca 62210, México
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11
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Geng L, Li Q, Jiao L, Xiang Y, Deng Q, Zhou DX, Zhao Y. WOX11 and CRL1 act synergistically to promote crown root development by maintaining cytokinin homeostasis in rice. THE NEW PHYTOLOGIST 2023; 237:204-216. [PMID: 36208055 DOI: 10.1111/nph.18522] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Crown root (CR) morphogenesis is critical for normal growth and nutrition absorption in cereals. In rice, WUSCHEL-RELATED HOMEOBOX11 (WOX11) and CROWN ROOTLESS1 (CRL1) play vital roles in controlling CR development. Despite their importance, whether and how the two regulators coordinate CR formation remains unclear. Electrophoretic mobility shift assays, transient expression, and chromatin immunoprecipitation qPCR suggested that WOX11 and CRL1 directly bind to OsCKX4 to regulate its expression during CR development. CRL1 enhances OsCKX4 activation through direct interaction with WOX11 at root emergence and elongation stages. Genetic dissection showed that the wox11/crl1 double mutant exhibits a more severe root phenotype. OsCKX4 knockout plants generated by CRISPR/Cas9 exhibited fewer CRs and higher cytokinin levels in the root meristem. Increased expression of OsCKX4 could partially complement the CR phenotypes of both crl1 and wox11 mutants. Furthermore, cytokinin can promote WOX11 protein accumulation in the root meristem. Together, these findings show that cytokinin accumulation is tightly regulated by the WOX11-CRL1 complex during CR elongation by counteracting the negative regulatory effects of cytokinin on root development. Importantly, these results reveal an intrinsic link between WOX11 protein accumulation and cytokinin to maintain CR growth.
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Affiliation(s)
- Leping Geng
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Qi Li
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Lele Jiao
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yimeng Xiang
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Qiyu Deng
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Dao-Xiu Zhou
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
- Institute of Plant Science Paris-Saclay (IPS2), CNRS, INRAE, University Paris-Saclay, Orsay, 91405, France
| | - Yu Zhao
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
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12
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Kazama Y, Kitoh M, Kobayashi T, Ishii K, Krasovec M, Yasui Y, Abe T, Kawano S, Filatov DA. A CLAVATA3-like Gene Acts as a Gynoecium Suppression Function in White Campion. Mol Biol Evol 2022; 39:msac195. [PMID: 36166820 PMCID: PMC9550985 DOI: 10.1093/molbev/msac195] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
How do separate sexes originate and evolve? Plants provide many opportunities to address this question as they have diverse mating systems and separate sexes (dioecy) that evolved many times independently. The classic "two-factor" model for evolution of separate sexes proposes that males and females can evolve from hermaphrodites via the spread of male and female sterility mutations that turn hermaphrodites into females and males, respectively. This widely accepted model was inspired by early genetic work in dioecious white campion (Silene latifolia) that revealed the presence of two sex-determining factors on the Y-chromosome, though the actual genes remained unknown. Here, we report identification and functional analysis of the putative sex-determining gene in S. latifolia, corresponding to the gynoecium suppression factor (GSF). We demonstrate that GSF likely corresponds to a Y-linked CLV3-like gene that is specifically expressed in early male flower buds and encodes the protein that suppresses gynoecium development in S. latifolia. Interestingly, GSFY has a dysfunctional X-linked homolog (GSFX) and their synonymous divergence (dS = 17.9%) is consistent with the age of sex chromosomes in this species. We propose that female development in S. latifolia is controlled via the WUSCHEL-CLAVATA feedback loop, with the X-linked WUSCHEL-like and Y-linked CLV3-like genes, respectively. Evolution of dioecy in the S. latifolia ancestor likely involved inclusion of ancestral GSFY into the nonrecombining region on the nascent Y-chromosome and GSFX loss of function, which resulted in disbalance of the WUSCHEL-CLAVATA feedback loop between the sexes and ensured gynoecium suppression in males.
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Affiliation(s)
- Yusuke Kazama
- Graduate School of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Kenjojima, Matsuoka, Eiheiji-cho, Japan
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Moe Kitoh
- Graduate School of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Kenjojima, Matsuoka, Eiheiji-cho, Japan
| | - Taiki Kobayashi
- Graduate School of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Kenjojima, Matsuoka, Eiheiji-cho, Japan
| | - Kotaro Ishii
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Marc Krasovec
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
- Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, 66650 Banyuls-sur-Mer, France
| | - Yasuo Yasui
- Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Tomoko Abe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Shigeyuki Kawano
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, FSB-601, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan
- Future Center Initiative, The University of Tokyo, 178-4-4 Wakashiba, Kashiwa, Chiba 277-0871, Japan
| | - Dmitry A Filatov
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
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13
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Rodriguez K, Do A, Senay-Aras B, Perales M, Alber M, Chen W, Reddy GV. Concentration-dependent transcriptional switching through a collective action of cis-elements. SCIENCE ADVANCES 2022; 8:eabo6157. [PMID: 35947668 PMCID: PMC9365274 DOI: 10.1126/sciadv.abo6157] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 06/23/2022] [Indexed: 06/15/2023]
Abstract
Gene expression specificity of homeobox transcription factors has remained paradoxical. WUSCHEL activates and represses CLAVATA3 transcription at lower and higher concentrations, respectively. We use computational modeling and experimental analysis to investigate the properties of the cis-regulatory module. We find that intrinsically each cis-element can only activate CLAVATA3 at a higher WUSCHEL concentration. However, together, they repress CLAVATA3 at higher WUSCHEL and activate only at lower WUSCHEL, showing that the concentration-dependent interactions among cis-elements regulate both activation and repression. Biochemical experiments show that two adjacent functional cis-elements bind WUSCHEL with higher affinity and dimerize at relatively lower levels. Moreover, increasing the distance between cis-elements prolongs WUSCHEL monomer binding window, resulting in higher CLAVATA3 activation. Our work showing a constellation of optimally spaced cis-elements of defined affinities determining activation and repression thresholds in regulating CLAVATA3 transcription provides a previously unknown mechanism of cofactor-independent regulation of transcription factor binding in mediating gene expression specificity.
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Affiliation(s)
- Kevin Rodriguez
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA 92521, USA
| | - Albert Do
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA 92521, USA
| | - Betul Senay-Aras
- Department of Mathematics, University of California Riverside, Riverside, CA 92521, USA
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California Riverside, Riverside, CA 92521, USA
| | - Mariano Perales
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA 92521, USA
| | - Mark Alber
- Department of Mathematics, University of California Riverside, Riverside, CA 92521, USA
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California Riverside, Riverside, CA 92521, USA
| | - Weitao Chen
- Department of Mathematics, University of California Riverside, Riverside, CA 92521, USA
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California Riverside, Riverside, CA 92521, USA
| | - G. Venugopala Reddy
- Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA 92521, USA
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California Riverside, Riverside, CA 92521, USA
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14
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Banwarth-Kuhn M, Rodriguez K, Michael C, Ta CK, Plong A, Bourgain-Chang E, Nematbakhsh A, Chen W, Roy-Chowdhury A, Reddy GV, Alber M. Combined computational modeling and experimental analysis integrating chemical and mechanical signals suggests possible mechanism of shoot meristem maintenance. PLoS Comput Biol 2022; 18:e1010199. [PMID: 35727850 PMCID: PMC9249181 DOI: 10.1371/journal.pcbi.1010199] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 07/01/2022] [Accepted: 05/12/2022] [Indexed: 11/19/2022] Open
Abstract
Stem cell maintenance in multilayered shoot apical meristems (SAMs) of plants requires strict regulation of cell growth and division. Exactly how the complex milieu of chemical and mechanical signals interact in the central region of the SAM to regulate cell division plane orientation is not well understood. In this paper, simulations using a newly developed multiscale computational model are combined with experimental studies to suggest and test three hypothesized mechanisms for the regulation of cell division plane orientation and the direction of anisotropic cell expansion in the corpus. Simulations predict that in the Apical corpus, WUSCHEL and cytokinin regulate the direction of anisotropic cell expansion, and cells divide according to tensile stress on the cell wall. In the Basal corpus, model simulations suggest dual roles for WUSCHEL and cytokinin in regulating both the direction of anisotropic cell expansion and cell division plane orientation. Simulation results are followed by a detailed analysis of changes in cell characteristics upon manipulation of WUSCHEL and cytokinin in experiments that support model predictions. Moreover, simulations predict that this layer-specific mechanism maintains both the experimentally observed shape and structure of the SAM as well as the distribution of WUSCHEL in the tissue. This provides an additional link between the roles of WUSCHEL, cytokinin, and mechanical stress in regulating SAM growth and proper stem cell maintenance in the SAM.
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Affiliation(s)
- Mikahl Banwarth-Kuhn
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California, Riverside, California, United States of America
- Department of Applied Mathematics, University of California, Merced, California, United States of America
- Department of Mathematics, University of California, Riverside, California, United States of America
| | - Kevin Rodriguez
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California, Riverside, California, United States of America
- Department of Botany and Plant Sciences, University of California, Riverside, California, United States of America
- Center for Plant Cell Biology, University of California, Riverside, California, United States of America
- Institute for Integrative Genome Biology, University of California, Riverside, California, United States of America
| | - Christian Michael
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California, Riverside, California, United States of America
- Department of Mathematics, University of California, Riverside, California, United States of America
| | - Calvin-Khang Ta
- Computer Science and Engineering Department, University of California, Riverside, California, United States of America
| | - Alexander Plong
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California, Riverside, California, United States of America
- Department of Botany and Plant Sciences, University of California, Riverside, California, United States of America
- Center for Plant Cell Biology, University of California, Riverside, California, United States of America
- Institute for Integrative Genome Biology, University of California, Riverside, California, United States of America
| | - Eric Bourgain-Chang
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California, Riverside, California, United States of America
- Department of Mathematics, University of California, Riverside, California, United States of America
| | - Ali Nematbakhsh
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California, Riverside, California, United States of America
- Department of Mathematics, University of California, Riverside, California, United States of America
| | - Weitao Chen
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California, Riverside, California, United States of America
- Department of Mathematics, University of California, Riverside, California, United States of America
| | - Amit Roy-Chowdhury
- Computer Science and Engineering Department, University of California, Riverside, California, United States of America
- Department of Electrical and Computer Engineering, University of California, Riverside, California, United States of America
| | - G. Venugopala Reddy
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California, Riverside, California, United States of America
- Department of Botany and Plant Sciences, University of California, Riverside, California, United States of America
- Center for Plant Cell Biology, University of California, Riverside, California, United States of America
- Institute for Integrative Genome Biology, University of California, Riverside, California, United States of America
| | - Mark Alber
- Interdisciplinary Center for Quantitative Modeling in Biology, University of California, Riverside, California, United States of America
- Department of Mathematics, University of California, Riverside, California, United States of America
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15
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Lambolez A, Kawamura A, Takahashi T, Rymen B, Iwase A, Favero DS, Ikeuchi M, Suzuki T, Cortijo S, Jaeger KE, Wigge PA, Sugimoto K. Warm Temperature Promotes Shoot Regeneration in Arabidopsis thaliana. PLANT & CELL PHYSIOLOGY 2022; 63:618-634. [PMID: 35157760 DOI: 10.1093/pcp/pcac017] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/14/2022] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
Many plants are able to regenerate upon cutting, and this process can be enhanced in vitro by incubating explants on hormone-supplemented media. While such protocols have been used for decades, little is known about the molecular details of how incubation conditions influence their efficiency. In this study, we find that warm temperature promotes both callus formation and shoot regeneration in Arabidopsis thaliana. We show that such an increase in shoot regenerative capacity at higher temperatures correlates with the enhanced expression of several regeneration-associated genes, such as CUP-SHAPED COTYLEDON 1 (CUC1) encoding a transcription factor involved in shoot meristem formation and YUCCAs (YUCs) encoding auxin biosynthesis enzymes. ChIP-sequencing analyses further reveal that histone variant H2A.Z is enriched on these loci at 17°C, while its occupancy is reduced by an increase in ambient temperature to 27°C. Moreover, we provide genetic evidence to demonstrate that H2A.Z acts as a repressor of de novo shoot organogenesis since H2A.Z-depleted mutants display enhanced shoot regeneration. This study thus uncovers a new chromatin-based mechanism that influences hormone-induced regeneration and additionally highlights incubation temperature as a key parameter for optimizing in vitro tissue culture.
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Affiliation(s)
- Alice Lambolez
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
- Department of Biological Sciences, Faculty of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyō-ku, Tōkyō 113-8654, Japan
| | - Ayako Kawamura
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Tatsuya Takahashi
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Bart Rymen
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
- Institut de Biologie Moléculaire des Plantes, Université de Strasbourg, 12 rue du Général Zimmer, Strasbourg 67084, France
| | - Akira Iwase
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - David S Favero
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Momoko Ikeuchi
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
- Department of Biology, Faculty of Science, Niigata University, Ikarashi, Niigata 950-2181, Japan
| | - Takamasa Suzuki
- College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan
| | - Sandra Cortijo
- UMR5004 Biochimie et Physiologie Moléculaire des Plantes, Université de Montpellier, CNRS, INRAE, Institut Agro, 2 place Pierre Viala, Montpellier 34060, France
| | - Katja E Jaeger
- Leibniz-Institut für Gemüse- und Zierpflanzenbau (IGZ) e.V., Theodor-Echtermeyer-Weg 1, Großbeeren 14979, Germany
| | - Philip A Wigge
- Leibniz-Institut für Gemüse- und Zierpflanzenbau (IGZ) e.V., Theodor-Echtermeyer-Weg 1, Großbeeren 14979, Germany
| | - Keiko Sugimoto
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
- Department of Biological Sciences, Faculty of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyō-ku, Tōkyō 113-8654, Japan
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16
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Shimotohno A. Illuminating the molecular mechanisms underlying shoot apical meristem homeostasis in plants. PLANT BIOTECHNOLOGY (TOKYO, JAPAN) 2022; 39:19-28. [PMID: 35800970 PMCID: PMC9200092 DOI: 10.5511/plantbiotechnology.22.0213a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 02/13/2022] [Indexed: 05/15/2023]
Abstract
Unlike animals, terrestrial plants are sessile and able to give rise to new organs throughout their lifetime. In the most extreme cases, they can survive for over a thousand years. With such protracted life cycles, plants have evolved sophisticated strategies to adapt to variable environments by coordinating their morphology as well as their growth, and have consequently acquired a high degree of developmental plasticity, which is supported by small groups of long-lived stem cells found in proliferative centers called meristems. Shoot apical meristems (SAMs) contain multipotent stem cells and provide a microenvironment that ensures both a self-renewable reservoir, to produce primordia and sustain growth, and a differentiating population that develops into all of the above-ground organs of land plants. The homeodomain transcription factor WUSCHEL (WUS) is expressed in the organizing center and acts as a master regulator to govern shoot stem cell homeostasis. In this review, I highlight recent advances in our understanding of the molecular mechanisms and signaling networks that underlie SAM maintenance, and discuss how plants utilize WUS to integrate intrinsic and extrinsic cues.
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Affiliation(s)
- Akie Shimotohno
- Institute of Transformative Bio-Molecules, Nagoya University, Nagoya, Aichi 464-8601, Japan
- E-mail: Tel: +81-52-789-2841 Fax: +81-52-789-3240
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17
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Shi B, Vernoux T. Hormonal control of cell identity and growth in the shoot apical meristem. CURRENT OPINION IN PLANT BIOLOGY 2022; 65:102111. [PMID: 34543915 DOI: 10.1016/j.pbi.2021.102111] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 08/12/2021] [Accepted: 08/15/2021] [Indexed: 06/13/2023]
Abstract
How cells acquire their identities and grow coordinately within a tissue is a fundamental question to understand plant development. In angiosperms, the shoot apical meristem (SAM) is a multicellular tissue containing a stem cell niche, which activity allows for a dynamic equilibrium between maintenance of stem cells and production of differentiated cells that are incorporated in new aerial tissues and lateral organs produced in the SAM. Plant hormones are small-molecule signals controlling many aspects of plant development and physiology. Several hormones are essential regulators of SAM activities. This review highlights current advances that are starting to decipher the complex mechanisms underlying the hormonal control of cell identity and growth in the SAM.
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Affiliation(s)
- Bihai Shi
- College of Agriculture, South China Agricultural University, 510642, Guangzhou, China; Guangdong Laboratory for Lingnan Modern Agriculture, 510642, Guangzhou, China; Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, CNRS, INRAE, F-69342, Lyon, France
| | - Teva Vernoux
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, CNRS, INRAE, F-69342, Lyon, France.
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18
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Pernisová M, Vernoux T. Auxin Does the SAMba: Auxin Signaling in the Shoot Apical Meristem. Cold Spring Harb Perspect Biol 2021; 13:a039925. [PMID: 33903154 PMCID: PMC8634999 DOI: 10.1101/cshperspect.a039925] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Plants, in contrast to animals, are unique in their capacity to postembryonically develop new organs due to the activity of stem cell populations, located in specialized tissues called meristems. Above ground, the shoot apical meristem generates aerial organs and tissues throughout plant life. It is well established that auxin plays a central role in the functioning of the shoot apical meristem. Auxin distribution in the meristem is not uniform and depends on the interplay between biosynthesis, transport, and degradation. Auxin maxima and minima are created, and result in transcriptional outputs that drive the development of new organs and contribute to meristem maintenance. To uncover and understand complex signaling networks such as the one regulating auxin responses in the shoot apical meristem remains a challenge. Here, we will discuss our current understanding and point to important research directions for the future.
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Affiliation(s)
- Markéta Pernisová
- Laboratoire Reproduction et Développement des Plantes, University at Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, 69342 Lyon, France
- Functional Genomics and Proteomics, National Centre for Biomolecula Research, Faculty of Science, Masaryk University and CEITEC MU, 62500 Brno, Czech Republic
| | - Teva Vernoux
- Laboratoire Reproduction et Développement des Plantes, University at Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, 69342 Lyon, France
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19
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CLAVATA3 mediated simultaneous control of transcriptional and post-translational processes provides robustness to the WUSCHEL gradient. Nat Commun 2021; 12:6361. [PMID: 34737298 PMCID: PMC8569176 DOI: 10.1038/s41467-021-26586-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 10/12/2021] [Indexed: 11/08/2022] Open
Abstract
Regulation of the homeodomain transcription factor WUSCHEL concentration is critical for stem cell homeostasis in Arabidopsis shoot apical meristems. WUSCHEL regulates the transcription of CLAVATA3 through a concentration-dependent activation-repression switch. CLAVATA3, a secreted peptide, activates receptor kinase signaling to repress WUSCHEL transcription. Considering the revised regulation, CLAVATA3 mediated repression of WUSCHEL transcription alone will lead to an unstable system. Here we show that CLAVATA3 signaling regulates nuclear-cytoplasmic partitioning of WUSCHEL to control nuclear levels and its diffusion into adjacent cells. Our work also reveals that WUSCHEL directly interacts with EXPORTINS via EAR-like domain which is also required for destabilizing WUSCHEL in the cytoplasm. We develop a combined experimental and computational modeling approach that integrates CLAVATA3-mediated transcriptional repression of WUSCHEL and post-translational control of nuclear levels with the WUSCHEL concentration-dependent regulation of CLAVATA3. We show that the dual control by the same signal forms a seamless connection between de novo WUSCHEL synthesis and sub-cellular partitioning in providing robustness to the WUSCHEL gradient.
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20
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Gonzalez JH, Taylor JS, Reed KM, Wright RC, Bargmann BOR. Temporal Control of Morphogenic Factor Expression Determines Efficacy in Enhancing Regeneration. PLANTS (BASEL, SWITZERLAND) 2021; 10:2271. [PMID: 34834634 PMCID: PMC8617614 DOI: 10.3390/plants10112271] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Regeneration of fertile plants from tissue culture is a critical bottleneck in the application of new plant breeding technologies. Ectopic overexpression of morphogenic factors is a promising workaround for this hurdle. METHODS Conditional overexpression of WUS and ARF5Δ was used to study the effect of timing the overexpression of these morphogenic factors during shoot regeneration from root explants in Arabidopsis. In addition, their effect on auxin-signaling activation was examined by visualization and cytometric quantification of the DR5:GFP auxin-signaling reporter in roots and protoplasts, respectively. RESULTS The induced expression of both WUS and ARF5Δ led to an activation of auxin signaling in roots. Activation of auxin signaling by WUS and ARF5Δ was further quantified by transient transformation of protoplasts. Ectopic overexpression of both WUS and ARF5Δ enhanced regeneration efficiency, but only during the shoot-induction stage of regeneration and not during the callus-induction stage. CONCLUSIONS The overexpression of WUS and ARF5Δ both lead to activation of auxin signaling. Expression during the shoot-induction stage is critical for the enhancement of shoot regeneration by WUS and ARF5Δ.
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Affiliation(s)
- Juan H Gonzalez
- School of Plant and Environmental Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA 24061, USA
| | - Joseph S Taylor
- School of Plant and Environmental Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA 24061, USA
| | - Kelsey M Reed
- School of Plant and Environmental Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA 24061, USA
| | - R Clay Wright
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA 24061, USA
| | - Bastiaan O R Bargmann
- School of Plant and Environmental Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA 24061, USA
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21
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Osmotic stress-induced somatic embryo maturation of coffee Coffea arabica L., shoot and root apical meristems development and robustness. Sci Rep 2021; 11:9661. [PMID: 33958620 PMCID: PMC8102543 DOI: 10.1038/s41598-021-88834-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 04/16/2021] [Indexed: 11/30/2022] Open
Abstract
Somatic embryogenesis (SE) is the most important plant biotechnology process for plant regeneration, propagation, genetic transformation and genome editing of coffee, Coffea arabica L. Somatic embryo (SEs) conversion to plantlets is the principal bottleneck for basic and applied use of this process. In this study we focus on the maturation of SEs of C. arabica var. Typica. SEs conversion to plantlet up to 95.9% was achieved under osmotic stress, using 9 g/L gelrite, as compared with only 39.34% in non-osmotic stress. Mature SEs induced in osmotic stress developed shoot and root apical meristems, while untreated SEs were unable to do it. C. arabica regenerated plants from osmotic stress were robust, with higher leaf and root area and internode length. To understand a possible regulatory mechanism, gene expression of key genes of C. arabica, homologous to sequences in the Arabidopsis thaliana genome, were analyzed. A set of two component system and cytokinin signaling-related coding genes (AHK1, AHK3, AHP4 and ARR1) which interact with WUSCHEL and WOX5 homedomains and morphogenic genes, BABY-BOOM, LEC1, FUS3 and AGL15, underwent significant changes during maturation of SEs of C. arabica var. Typica. This protocol is currently being applied in genetic transformation with high rate of success.
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22
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Umeda M, Ikeuchi M, Ishikawa M, Ito T, Nishihama R, Kyozuka J, Torii KU, Satake A, Goshima G, Sakakibara H. Plant stem cell research is uncovering the secrets of longevity and persistent growth. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:326-335. [PMID: 33533118 PMCID: PMC8252613 DOI: 10.1111/tpj.15184] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/26/2021] [Accepted: 01/28/2021] [Indexed: 05/07/2023]
Abstract
Plant stem cells have several extraordinary features: they are generated de novo during development and regeneration, maintain their pluripotency, and produce another stem cell niche in an orderly manner. This enables plants to survive for an extended period and to continuously make new organs, representing a clear difference in their developmental program from animals. To uncover regulatory principles governing plant stem cell characteristics, our research project 'Principles of pluripotent stem cells underlying plant vitality' was launched in 2017, supported by a Grant-in-Aid for Scientific Research on Innovative Areas from the Japanese government. Through a collaboration involving 28 research groups, we aim to identify key factors that trigger epigenetic reprogramming and global changes in gene networks, and thereby contribute to stem cell generation. Pluripotent stem cells in the shoot apical meristem are controlled by cytokinin and auxin, which also play a crucial role in terminating stem cell activity in the floral meristem; therefore, we are focusing on biosynthesis, metabolism, transport, perception, and signaling of these hormones. Besides, we are uncovering the mechanisms of asymmetric cell division and of stem cell death and replenishment under DNA stress, which will illuminate plant-specific features in preserving stemness. Our technology support groups expand single-cell omics to describe stem cell behavior in a spatiotemporal context, and provide correlative light and electron microscopic technology to enable live imaging of cell and subcellular dynamics at high spatiotemporal resolution. In this perspective, we discuss future directions of our ongoing projects and related research fields.
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Affiliation(s)
- Masaaki Umeda
- Graduate School of Science and TechnologyNara Institute of Science and TechnologyIkoma630‐0192Japan
| | - Momoko Ikeuchi
- Department of BiologyFaculty of ScienceNiigata UniversityNiigata950‐2181Japan
| | - Masaki Ishikawa
- National Institute for Basic BiologyOkazaki444‐8585Japan
- Department of Basic BiologyThe Graduate University for Advanced Studies (SOKENDAI)Okazaki444‐8585Japan
| | - Toshiro Ito
- Graduate School of Science and TechnologyNara Institute of Science and TechnologyIkoma630‐0192Japan
| | | | - Junko Kyozuka
- Graduate School of Life SciencesTohoku UniversitySendai980‐8577Japan
| | - Keiko U. Torii
- Howard Hughes Medical Institute and Department of Molecular BiosciencesThe University of Texas at AustinAustinTX78712USA
- Institute of Transformative Biomolecules (WPI‐ITbM)Nagoya UniversityNagoya464‐8601Japan
| | - Akiko Satake
- Department of BiologyFaculty of ScienceKyushu UniversityFukuoka819‐0395Japan
| | - Gohta Goshima
- Division of Biological ScienceGraduate School of ScienceNagoya UniversityNagoya464‐8602Japan
- Sugashima Marine Biological LaboratoryGraduate School of ScienceNagoya UniversityToba517‐0004Japan
| | - Hitoshi Sakakibara
- Graduate School of Bioagricultural SciencesNagoya UniversityNagoya464‐8601Japan
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23
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Ikeda Y, Zalabák D, Kubalová I, Králová M, Brenner WG, Aida M. Interpreting Cytokinin Action as Anterograde Signaling and Beyond. FRONTIERS IN PLANT SCIENCE 2021; 12:641257. [PMID: 33854521 PMCID: PMC8039514 DOI: 10.3389/fpls.2021.641257] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 03/08/2021] [Indexed: 05/22/2023]
Abstract
Among the major phytohormones, the cytokinin exhibits unique features for its ability to positively affect the developmental status of plastids. Even early on in its research, cytokinins were known to promote plastid differentiation and to reduce the loss of chlorophyll in detached leaves. Since the discovery of the components of cytokinin perception and primary signaling, the genes involved in photosynthesis and plastid differentiation have been identified as those directly targeted by type-B response regulators. Furthermore, cytokinins are known to modulate versatile cellular processes such as promoting the division and differentiation of cells and, in concert with auxin, initiating the de novo formation of shoot apical meristem (SAM) in tissue cultures. Yet how cytokinins precisely participate in such diverse cellular phenomena, and how the associated cellular processes are coordinated as a whole, remains unclear. A plausible presumption that would account for the coordinated gene expression is the tight and reciprocal communication between the nucleus and plastid. The fact that cytokinins affect plastid developmental status via gene expression in both the nucleus and plastid is interpreted here to suggest that cytokinin functions as an initiator of anterograde (nucleus-to-plastid) signaling. Based on this viewpoint, we first summarize the physiological relevance of cytokinins to the coordination of plastid differentiation with de novo shoot organogenesis in tissue culture systems. Next, the role of endogenous cytokinins in influencing plastid differentiation within the SAM of intact plants is discussed. Finally, a presumed plastid-derived signal in response to cytokinins for coupled nuclear gene expression is proposed.
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Affiliation(s)
- Yoshihisa Ikeda
- Centre of the Region Haná for Biotechnological and Agricultural Research, Czech Advanced Technology and Research Institute, Palacký University, Olomouc, Czechia
| | - David Zalabák
- Laboratory of Growth Regulators, Palacky University and Institute of Experimental Botany AS CR, Olomouc, Czechia
| | - Ivona Kubalová
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Michaela Králová
- Centre of the Region Haná for Biotechnological and Agricultural Research, Czech Advanced Technology and Research Institute, Palacký University, Olomouc, Czechia
| | - Wolfram G. Brenner
- General and Applied Botany, Institute of Biology, Universität Leipzig, Leipzig, Germany
| | - Mitsuhiro Aida
- International Research Organization for Advanced Science and Technology (IROAST), Kumamoto University, Kumamoto, Japan
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Tvorogova VE, Krasnoperova EY, Potsenkovskaia EA, Kudriashov AA, Dodueva IE, Lutova LA. What Does the WOX Say? Review of Regulators, Targets, Partners. Mol Biol 2021. [DOI: 10.1134/s002689332102031x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Wang C, Zhao B, He L, Zhou S, Liu Y, Zhao W, Guo S, Wang R, Bai Q, Li Y, Wang D, Wu Q, Yang Y, Liu Y, Tadege M, Chen J. The WOX family transcriptional regulator SlLAM1 controls compound leaf and floral organ development in Solanum lycopersicum. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:1822-1835. [PMID: 33277994 PMCID: PMC7921304 DOI: 10.1093/jxb/eraa574] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 12/03/2020] [Indexed: 05/26/2023]
Abstract
Plant-specific WOX family transcription factors play important roles ranging from embryogenesis to lateral organ development. The WOX1 transcription factors, which belong to the modern clade of the WOX family, are known to regulate outgrowth of the leaf blade specifically in the mediolateral axis; however, the role of WOX1 in compound leaf development remains unknown. Phylogenetic analysis of the whole WOX family in tomato (Solanum lycopersicum) indicates that there are 10 members that represent the modern, intermediate, and ancient clades. Using phylogenetic analysis and a reverse genetic approach, in this study we identified SlLAM1 in the modern clade and examined its function and tissue-specific expression pattern. We found that knocking out SlLAM1 via CRISPR/Cas9-mediated genome editing led to narrow leaves and a reduced number of secondary leaflets. Overexpression of tomato SlLAM1 could rescue the defects of the tobacco lam1 mutant. Anatomical and transcriptomic analyses demonstrated that floral organ development, fruit size, secondary leaflet initiation, and leaf complexity were altered due to loss-of-function of SlLAM1. These findings demonstrate that tomato SlLAM1 plays an important role in the regulation of secondary leaflet initiation, in addition to its conserved function in blade expansion.
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Affiliation(s)
- Chaoqun Wang
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Baolin Zhao
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Liangliang He
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Shaoli Zhou
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ye Liu
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Weiyue Zhao
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Shiqi Guo
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ruoruo Wang
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Quanzi Bai
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Youhan Li
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Dongfa Wang
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Qing Wu
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yuanfan Yang
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- School of Ecology and Environmental Sciences, Yunnan University, Kunming, China
| | - Yu Liu
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Million Tadege
- Department of Plant and Soil Sciences, Institute for Agricultural Biosciences, Oklahoma State University, 3210 Sam Noble Parkway, Ardmore, OK, USA
| | - Jianghua Chen
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, CAS Center for Excellence for Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, China
- School of Life Sciences, University of Science and Technology of China, Hefei, China
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26
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Wolabu TW, Wang H, Tadesse D, Zhang F, Behzadirad M, Tvorogova VE, Abdelmageed H, Liu Y, Chen N, Chen J, Allen RD, Tadege M. WOX9 functions antagonistic to STF and LAM1 to regulate leaf blade expansion in Medicago truncatula and Nicotiana sylvestris. THE NEW PHYTOLOGIST 2021; 229:1582-1597. [PMID: 32964420 DOI: 10.1111/nph.16934] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
WOX family transcription factors regulate multiple developmental programs. The intermediate clade transcriptional activator WOX9 functions together with the modern clade transcriptional repressor WOX genes in embryogenesis and meristems maintenance, but the mechanism of this interaction is unclear. STF and LAM1 are WOX1 orthologs required for leaf blade outgrowth in Medicago truncatula and Nicotiana sylvestris, respectively. Using biochemical methods and genome editing technology, here we show that WOX9 is an abaxial factor and functions antagonistically to STF and LAM1 to regulate leaf blade development. While NsWOX9 ectopic expression enhances the lam1 mutant phenotype, and antisense expression partially rescues the lam1 mutant, both overexpression and knockout of NsWOX9 in N. sylvestris resulted in a range of severe leaf blade distortions, indicating important role in blade development. Our results indicate that direct repression of WOX9 by WUS clade repressor STF/LAM1 is required for correct blade architecture and patterning in M. truncatula and N. sylvestris. These findings suggest that controlling transcriptional activation and repression mechanisms by direct interaction of activator and repressor WOX genes may be required for cell proliferation and differentiation homeostasis, and could be an evolutionarily conserved mechanism for the development of complex and diverse morphology in flowering plants.
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Affiliation(s)
- Tezera W Wolabu
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
- Noble Research Institute, LLC, Ardmore, OK, 73401, USA
| | - Hui Wang
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
- College of Grassland Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Dimiru Tadesse
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
| | - Fei Zhang
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06520-8104, USA
| | - Marjan Behzadirad
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
| | - Varvara E Tvorogova
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
- Department of Genetics and Biotechnology, St Petersburg State University, St Petersburg, 199034, Russia
| | - Haggag Abdelmageed
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
- Department of Agricultural Botany, Faculty of Agriculture, Cairo University, Giza,, 12613, Egypt
| | - Ye Liu
- School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Naichong Chen
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Jianghua Chen
- CAS Key Laboratory of Topical Plant Resources and Sustainable Use, CAS Center for Excellence in Molecular Plant Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan, 650223, China
| | - Randy D Allen
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Million Tadege
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, 73401, USA
- Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK, 74078, USA
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27
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Nalapalli S, Tunc-Ozdemir M, Sun Y, Elumalai S, Que Q. Morphogenic Regulators and Their Application in Improving Plant Transformation. Methods Mol Biol 2021; 2238:37-61. [PMID: 33471323 DOI: 10.1007/978-1-0716-1068-8_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Generation of plant lines with transgene or edited gene variants is the desired outcome of transformation technology. Conventional DNA-based plant transformation methods are the most commonly used technology but these approaches are limited to a small number of plant species with efficient transformation systems. The ideal transformation technologies are those that allow biotechnology applications across wide genetic background, especially within elite germplasm of major crop species. This chapter will briefly review key regulatory genes involved in plant morphogenesis with a focus on in vitro somatic embryogenesis and their application in improving plant transformation.
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Affiliation(s)
- Samson Nalapalli
- Seeds Research, Syngenta Crop Protection LLC, Research Triangle Park, NC, USA.
| | | | - Yuejin Sun
- Seeds Research, Syngenta Crop Protection LLC, Research Triangle Park, NC, USA
| | - Sivamani Elumalai
- Seeds Research, Syngenta Crop Protection LLC, Research Triangle Park, NC, USA
| | - Qiudeng Que
- Seeds Research, Syngenta Crop Protection LLC, Research Triangle Park, NC, USA
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28
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Gundu S, Tabassum N, Blilou I. Moving with purpose and direction: transcription factor movement and cell fate determination revisited. CURRENT OPINION IN PLANT BIOLOGY 2020; 57:124-132. [PMID: 32992134 DOI: 10.1016/j.pbi.2020.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 07/13/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
Cell diversity in a multicellular organism relies on cell-cell communication where cells must receive positional information as input signals to adopt their proper cell fate in the right place and at the right time. This process is achieved through triggering signaling cascades that drive cellular changes during development. In plants, signaling through mobile transcription factors (TF) plays a central role in development. Rather than acting cell-autonomously and exclusive to their expression domains, many TFs move between cells and deploy regulatory networks and cell type-specific effectors to achieve their biological functions. Here, we highlight a few examples of mobile TFs central to cell fate specification in Arabidopsis.
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Affiliation(s)
- Shyam Gundu
- Laboratory of Plant Cell and Developmental Biology, King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering (BESE), Thuwal, 23955-6900, Saudi Arabia
| | - Naheed Tabassum
- Laboratory of Plant Cell and Developmental Biology, King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering (BESE), Thuwal, 23955-6900, Saudi Arabia
| | - Ikram Blilou
- Laboratory of Plant Cell and Developmental Biology, King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering (BESE), Thuwal, 23955-6900, Saudi Arabia.
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29
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Liu Z, Dai X, Li J, Liu N, Liu X, Li S, Xiang F. The Type-B Cytokinin Response Regulator ARR1 Inhibits Shoot Regeneration in an ARR12-Dependent Manner in Arabidopsis. THE PLANT CELL 2020; 32:2271-2291. [PMID: 32398274 PMCID: PMC7346554 DOI: 10.1105/tpc.19.00022] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 04/15/2020] [Accepted: 05/09/2020] [Indexed: 05/08/2023]
Abstract
Exogenous cytokinin is critical for in vitro shoot regeneration. Proteins involved in the cytokinin signal transduction pathway, including type-B ARABIDOPSIS RESPONSE REGULATORs (ARRs), participate in shoot regeneration in Arabidopsis (Arabidopsis thaliana). Some type-B ARRs (e.g., ARR1 and ARR12) promote shoot regeneration by directly activating WUSCHEL (WUS) expression; however, it is unclear how type-B ARRs inhibit shoot regeneration. Here, we show that ARR12 is a central enhancer of callus formation and shoot regeneration, whereas ARR1 is a strong inhibitor of this process that counteracts the positive effect of ARR12. ARR1 indirectly represses CLAVATA3 (CLV3) expression in an ARR12-dependent manner via competing with ARR12 for binding to the CLV3 promoter, which contributes to its ARR12-dependent inhibitory effect on callus formation and shoot regeneration. In parallel, ARR1 inhibits shoot regeneration through transcriptional activation of INDOLE-3-ACETIC ACID INDUCIBLE17, an auxin response repressor gene, and the consequent indirect repression of WUS expression. Thus, type-B ARRs have diverse effects on callus formation and shoot regeneration. Our study reveals novel molecular pathways linking cytokinin signaling, the CLV3 regulator, and auxin signaling, and sheds light on the mechanism underlying cytokinin-regulated shoot regeneration.
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Affiliation(s)
- Zhenhua Liu
- The Key Laboratory of the Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong 266237, China
| | - Xuehuan Dai
- The Key Laboratory of the Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong 266237, China
| | - Juan Li
- The Key Laboratory of the Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong 266237, China
| | - Na Liu
- The Key Laboratory of the Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong 266237, China
| | - Xiangzheng Liu
- The Key Laboratory of the Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong 266237, China
| | - Shuo Li
- The Key Laboratory of the Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong 266237, China
| | - Fengning Xiang
- The Key Laboratory of the Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, Shandong 266237, China
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30
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Cao X, Jiao Y. Control of cell fate during axillary meristem initiation. Cell Mol Life Sci 2020; 77:2343-2354. [PMID: 31807816 PMCID: PMC11105066 DOI: 10.1007/s00018-019-03407-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 11/21/2019] [Accepted: 11/28/2019] [Indexed: 01/17/2023]
Abstract
Axillary meristems (AMs) are located in the leaf axil and can establish new growth axes. Whereas their neighboring cells are differentiated, the undifferentiated cells in the AM endow the AM with the same developmental potential as the shoot apical meristem. The AM is, therefore, an excellent system to study stem cell fate maintenance in plants. In this review, we summarize the current knowledge of AM initiation. Recent findings have shown that AMs derive from a stem cell lineage that is maintained in the leaf axil. This review covers AM progenitor cell fate maintenance, reactivation, and meristem establishment. We also highlight recent work that links transcription factors, phytohormones, and epigenetic regulation to AM initiation.
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Affiliation(s)
- Xiuwei Cao
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yuling Jiao
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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31
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Han H, Liu X, Zhou Y. Transcriptional circuits in control of shoot stem cell homeostasis. CURRENT OPINION IN PLANT BIOLOGY 2020; 53:50-56. [PMID: 31766002 DOI: 10.1016/j.pbi.2019.10.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 10/16/2019] [Accepted: 10/17/2019] [Indexed: 05/02/2023]
Abstract
Plant shoot apical meristems (SAMs) play essential roles in plant growth and development. Located at the growing tip of a plant stem, these dome-like structures contain stem cells, which serve to perpetuate themselves in an undifferentiated state while continually adding new cells that differentiate and eventually form all above-ground tissues. In a SAM, the pool of stem cells is dynamically maintained through a balance between cell division (self-renewal) and differentiation (loss of stem-cell identity). In the model plant Arabidopsis thaliana, a negative feedback loop between WUSCHEL (WUS) and the CLAVATA3 (CLV3) plays important roles in maintaining the stem cell population. In this review, we highlight recent findings mainly from studies in Arabidopsis, and summarize the research progress on understanding how multiple transcriptional circuits integrate and function at different cell layers to control the WUS-CLV3 loop and stem cell homeostasis.
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Affiliation(s)
- Han Han
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, United States; Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, United States
| | - Xing Liu
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, United States; Department of Biochemistry, Purdue University, West Lafayette, IN 47907, United States
| | - Yun Zhou
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, United States; Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, United States.
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32
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Shoot meristem maintenance and immune response signaling converge at the G protein β subunit. Proc Natl Acad Sci U S A 2020; 117:1842-1844. [PMID: 31937659 DOI: 10.1073/pnas.1921255117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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33
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Li SN, Cheng P, Bai YQ, Shi Y, Yu JY, Li RC, Zhou RN, Zhang ZG, Wu XX, Chen QS. Analysis of Soybean Somatic Embryogenesis Using Chromosome Segment Substitution Lines and Transcriptome Sequencing. Genes (Basel) 2019; 10:E943. [PMID: 31752416 PMCID: PMC6896167 DOI: 10.3390/genes10110943] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 11/05/2019] [Accepted: 11/18/2019] [Indexed: 12/15/2022] Open
Abstract
Soybean is an important cash crop that is widely used as a source of vegetable protein and edible oil. The regeneration ability of soybean directly affects the application of biotechnology. In this study, we used the exogenous hormone 2,4-D to treat immature embryos. Different levels of somatic incidence were selected from the chromosome segment substitution lines (CSSLs) constructed by SN14 and ZYD00006. Transcriptome sequencing of extreme materials was performed, and 2666 differentially expressed genes were obtained. At the same time, a difference table was generated by combining the data on CSSL rearrangement. In the extreme materials, a total of 93 differentially expressed genes were predicted and were then analyzed by cluster analysis and Gene Ontology (GO) annotation. After screening and annotating the target genes, three differentially expressed genes with hormone pathways were identified. The expression patterns of the target genes were verified by real-time quantitative PCR (qRT-PCR). Haplotype polymorphism detection and linkage disequilibrium analysis were performed on the candidate gene Glyma.09g248200. This study provided more information on the regulation network of soybean somatic embryogenesis and regeneration processes, and further identified important genes in the soybean regeneration process and provided a theoretical basis for accelerating the application of biotechnology to soybean for improving its breeding efficiency.
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Affiliation(s)
| | | | | | | | | | | | | | - Zhan-Guo Zhang
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China; (S.-N.L.); (P.C.); (Y.-Q.B.); (Y.S.); (J.-Y.Y.); (R.-C.L.); (R.-N.Z.)
| | - Xiao-Xia Wu
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China; (S.-N.L.); (P.C.); (Y.-Q.B.); (Y.S.); (J.-Y.Y.); (R.-C.L.); (R.-N.Z.)
| | - Qing-Shan Chen
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, China; (S.-N.L.); (P.C.); (Y.-Q.B.); (Y.S.); (J.-Y.Y.); (R.-C.L.); (R.-N.Z.)
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34
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Zúñiga-Mayo VM, Gómez-Felipe A, Herrera-Ubaldo H, de Folter S. Gynoecium development: networks in Arabidopsis and beyond. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:1447-1460. [PMID: 30715461 DOI: 10.1093/jxb/erz026] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 01/14/2019] [Indexed: 05/27/2023]
Abstract
Life has always found a way to preserve itself. One strategy that has been developed for this purpose is sexual reproduction. In land plants, the gynoecium is considered to be at the top of evolutionary innovation, since it has been a key factor in the success of the angiosperms. The gynoecium is composed of carpels with different tissues that need to develop and differentiate in the correct way. In order to control and guide gynoecium development, plants have adapted elements of pre-existing gene regulatory networks (GRNs) but new ones have also evolved. The GRNs can interact with internal factors (e.g. hormones and other metabolites) and external factors (e.g. mechanical signals and temperature) at different levels, giving robustness and flexibility to gynoecium development. Here, we review recent findings regarding the role of cytokinin-auxin crosstalk and the genes that connect these hormonal pathways during early gynoecium development. We also discuss some examples of internal and external factors that can modify GRNs. Finally, we make a journey through the flowering plant lineage to determine how conserved are these GRNs that regulate gynoecium and fruit development.
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Affiliation(s)
- Victor M Zúñiga-Mayo
- Unidad de Genómica Avanzada (LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Guanajuato, México
| | - Andrea Gómez-Felipe
- Unidad de Genómica Avanzada (LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Guanajuato, México
| | - Humberto Herrera-Ubaldo
- Unidad de Genómica Avanzada (LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Guanajuato, México
| | - Stefan de Folter
- Unidad de Genómica Avanzada (LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Guanajuato, México
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35
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Uchida N, Torii KU. Stem cells within the shoot apical meristem: identity, arrangement and communication. Cell Mol Life Sci 2019; 76:1067-1080. [PMID: 30523363 PMCID: PMC11105333 DOI: 10.1007/s00018-018-2980-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/06/2018] [Accepted: 11/26/2018] [Indexed: 10/27/2022]
Abstract
Stem cells are specific cells that renew themselves and also provide daughter cells for organ formation. In plants, primary stem cell populations are nurtured within shoot and root apical meristems (SAM and RAM) for the production of aerial and underground parts, respectively. This review article summarizes recent progress on control of stem cells in the SAM from studies of the model plant Arabidopsis thaliana. To that end, a brief overview of the RAM is provided first to emphasize similarities and differences between the two apical meristems, which would help in better understanding of stem cells in the SAM. Subsequently, we will discuss in depth how stem cells are arranged in an organized manner in the SAM, how dynamically the stem cell identity is regulated, what factors participate in stem cell control, and how intercellular communication by mobile signals modulates stem cell behaviors within the SAM. Remaining questions and perspectives are also presented for future studies.
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Affiliation(s)
- Naoyuki Uchida
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan.
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan.
| | - Keiko U Torii
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
- Department of Biology, University of Washington, Seattle, WA, 98195, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, 98195, USA
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McKim SM. How plants grow up. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2019; 61:257-277. [PMID: 30697935 DOI: 10.1111/jipb.12786] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 01/21/2019] [Indexed: 05/27/2023]
Abstract
A plant's lateral structures, such as leaves, branches and flowers, literally hinge on the shoot axis, making its integrity and growth fundamental to plant form. In all plants, subapical proliferation within the shoot tip displaces cells downward to extrude the cylindrical stem. Following the transition to flowering, many plants show extensive axial elongation associated with increased subapical proliferation and expansion. However, the cereal grasses also elongate their stems, called culms, due to activity within detached intercalary meristems which displaces cells upward, elevating the grain-bearing inflorescence. Variation in culm length within species is especially relevant to cereal crops, as demonstrated by the high-yielding semi-dwarfed cereals of the Green Revolution. Although previously understudied, recent renewed interest the regulation of subapical and intercalary growth suggests that control of cell division planes, boundary formation and temporal dynamics of differentiation, are likely critical mechanisms coordinating axial growth and development in plants.
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Affiliation(s)
- Sarah M McKim
- Division of Plant Sciences, University of Dundee at The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
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Gordon-Kamm B, Sardesai N, Arling M, Lowe K, Hoerster G, Betts S, Jones AT. Using Morphogenic Genes to Improve Recovery and Regeneration of Transgenic Plants. PLANTS (BASEL, SWITZERLAND) 2019; 8:E38. [PMID: 30754699 PMCID: PMC6409764 DOI: 10.3390/plants8020038] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 01/29/2019] [Accepted: 01/31/2019] [Indexed: 12/31/2022]
Abstract
Efficient transformation of numerous important crops remains a challenge, due predominantly to our inability to stimulate growth of transgenic cells capable of producing plants. For years, this difficulty has been partially addressed by tissue culture strategies that improve regeneration either through somatic embryogenesis or meristem formation. Identification of genes involved in these developmental processes, designated here as morphogenic genes, provides useful tools in transformation research. In species from eudicots and cereals to gymnosperms, ectopic overexpression of genes involved in either embryo or meristem development has been used to stimulate growth of transgenic plants. However, many of these genes produce pleiotropic deleterious phenotypes. To mitigate this, research has been focusing on ways to take advantage of growth-stimulating morphogenic genes while later restricting or eliminating their expression in the plant. Methods of controlling ectopic overexpression include the use of transient expression, inducible promoters, tissue-specific promoters, and excision of the morphogenic genes. These methods of controlling morphogenic gene expression have been demonstrated in a variety of important crops. Here, we provide a review that highlights how ectopic overexpression of genes involved in morphogenesis has been used to improve transformation efficiencies, which is facilitating transformation of numerous recalcitrant crops. The use of morphogenic genes may help to alleviate one of the bottlenecks currently slowing progress in plant genome modification.
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Affiliation(s)
- Bill Gordon-Kamm
- Corteva Agriscience™, Agriculture Division of DowDuPont, Johnston, IA 50131, USA.
| | - Nagesh Sardesai
- Corteva Agriscience™, Agriculture Division of DowDuPont, Johnston, IA 50131, USA.
| | - Maren Arling
- Corteva Agriscience™, Agriculture Division of DowDuPont, Johnston, IA 50131, USA.
| | - Keith Lowe
- Corteva Agriscience™, Agriculture Division of DowDuPont, Johnston, IA 50131, USA.
| | - George Hoerster
- Corteva Agriscience™, Agriculture Division of DowDuPont, Johnston, IA 50131, USA.
| | - Scott Betts
- Corteva Agriscience™, Agriculture Division of DowDuPont, Johnston, IA 50131, USA.
| | - And Todd Jones
- Corteva Agriscience™, Agriculture Division of DowDuPont, Johnston, IA 50131, USA.
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Cell-Based Model of the Generation and Maintenance of the Shape and Structure of the Multilayered Shoot Apical Meristem of Arabidopsis thaliana. Bull Math Biol 2018; 81:3245-3281. [PMID: 30552627 DOI: 10.1007/s11538-018-00547-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 11/28/2018] [Indexed: 01/28/2023]
Abstract
One of the central problems in animal and plant developmental biology is deciphering how chemical and mechanical signals interact within a tissue to produce organs of defined size, shape, and function. Cell walls in plants impose a unique constraint on cell expansion since cells are under turgor pressure and do not move relative to one another. Cell wall extensibility and constantly changing distribution of stress on the wall are mechanical properties that vary between individual cells and contribute to rates of expansion and orientation of cell division. How exactly cell wall mechanical properties influence cell behavior is still largely unknown. To address this problem, a novel, subcellular element computational model of growth of stem cells within the multilayered shoot apical meristem (SAM) of Arabidopsis thaliana is developed and calibrated using experimental data. Novel features of the model include separate, detailed descriptions of cell wall extensibility and mechanical stiffness, deformation of the middle lamella, and increase in cytoplasmic pressure generating internal turgor pressure. The model is used to test novel hypothesized mechanisms of formation of the shape and structure of the growing, multilayered SAM based on WUS concentration of individual cells controlling cell growth rates and layer-dependent anisotropic mechanical properties of subcellular components of individual cells determining anisotropic cell expansion directions. Model simulations also provide a detailed prediction of distribution of stresses in the growing tissue which can be tested in future experiments.
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