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Gazzarrini S, Song L. LAFL Factors in Seed Development and Phase Transitions. ANNUAL REVIEW OF PLANT BIOLOGY 2024; 75:459-488. [PMID: 38657282 DOI: 10.1146/annurev-arplant-070623-111458] [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: 04/26/2024]
Abstract
Development is a chain reaction in which one event leads to another until the completion of a life cycle. Phase transitions are milestone events in the cycle of life. LEAFY COTYLEDON1 (LEC1), ABA INSENSITIVE3 (ABI3), FUSCA3 (FUS3), and LEC2 proteins, collectively known as LAFL, are master transcription factors (TFs) regulating seed and other developmental processes. Since the initial characterization of the LAFL genes, more than three decades of active research has generated tremendous amounts of knowledge about these TFs, whose roles in seed development and germination have been comprehensively reviewed. Recent advances in cell biology with genetic and genomic tools have allowed the characterization of the LAFL regulatory networks in previously challenging tissues at a higher throughput and resolution in reference species and crops. In this review, we provide a holistic perspective by integrating advances at the epigenetic, transcriptional, posttranscriptional, and protein levels to exemplify the spatiotemporal regulation of the LAFL networks in Arabidopsis seed development and phase transitions, and we briefly discuss the evolution of these TF networks.
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Affiliation(s)
- Sonia Gazzarrini
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada;
| | - Liang Song
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada;
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2
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Poethig RS, Fouracre J. Temporal regulation of vegetative phase change in plants. Dev Cell 2024; 59:4-19. [PMID: 38194910 PMCID: PMC10783531 DOI: 10.1016/j.devcel.2023.11.010] [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: 07/17/2023] [Revised: 10/11/2023] [Accepted: 11/13/2023] [Indexed: 01/11/2024]
Abstract
During their vegetative growth, plants reiteratively produce leaves, buds, and internodes at the apical end of the shoot. The identity of these organs changes as the shoot develops. Some traits change gradually, but others change in a coordinated fashion, allowing shoot development to be divided into discrete juvenile and adult phases. The transition between these phases is called vegetative phase change. Historically, vegetative phase change has been studied because it is thought to be associated with an increase in reproductive competence. However, this is not true for all species; indeed, heterochronic variation in the timing of vegetative phase change and flowering has made important contributions to plant evolution. In this review, we describe the molecular mechanism of vegetative phase change, how the timing of this process is controlled by endogenous and environmental factors, and its ecological and evolutionary significance.
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Affiliation(s)
- R Scott Poethig
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Jim Fouracre
- School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK
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3
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Hjertaas AC, Preston JC, Kainulainen K, Humphreys AM, Fjellheim S. Convergent evolution of the annual life history syndrome from perennial ancestors. FRONTIERS IN PLANT SCIENCE 2023; 13:1048656. [PMID: 36684797 PMCID: PMC9846227 DOI: 10.3389/fpls.2022.1048656] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Despite most angiosperms being perennial, once-flowering annuals have evolved multiple times independently, making life history traits among the most labile trait syndromes in flowering plants. Much research has focused on discerning the adaptive forces driving the evolution of annual species, and in pinpointing traits that distinguish them from perennials. By contrast, little is known about how 'annual traits' evolve, and whether the same traits and genes have evolved in parallel to affect independent origins of the annual syndrome. Here, we review what is known about the distribution of annuals in both phylogenetic and environmental space and assess the evidence for parallel evolution of annuality through similar physiological, developmental, and/or genetic mechanisms. We then use temperate grasses as a case study for modeling the evolution of annuality and suggest future directions for understanding annual-perennial transitions in other groups of plants. Understanding how convergent life history traits evolve can help predict species responses to climate change and allows transfer of knowledge between model and agriculturally important species.
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Affiliation(s)
- Ane C. Hjertaas
- Department of Plant Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway
| | - Jill C. Preston
- Department of Plant Biology, The University of Vermont, Burlington, VT, United States
| | - Kent Kainulainen
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
| | - Aelys M. Humphreys
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
- Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
| | - Siri Fjellheim
- Department of Plant Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway
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4
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Poethig RS, Cullina WL, Doody E, Floyd T, Fouracre JP, Hu T, Xu M, Zhao J. Short-interval traffic lines: versatile tools for genetic analysis in Arabidopsis thaliana. G3 (BETHESDA, MD.) 2022; 12:6677228. [PMID: 36018241 PMCID: PMC9526051 DOI: 10.1093/g3journal/jkac202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 07/17/2022] [Indexed: 12/30/2022]
Abstract
Traffic lines are transgenic stocks of Arabidopsis thaliana that contain a pair of linked seed-specific eGFP and DsRed markers. These stocks were originally developed for the purpose of studying recombination, but can also be used to follow the inheritance of unmarked chromosomes placed in trans to the marked chromosome. They are particularly useful for this latter purpose if the distance between markers is short, making double recombination within this interval relatively rare. We generated 163 traffic lines that cover the Arabidopsis genome in overlapping intervals of approximately 1.2 Mb (6.9 cM). These stocks make it possible to predict the genotype of a plant based on its seed fluorescence (or lack thereof) and facilitate many experiments in genetic analysis that are difficult, tedious, or expensive to perform using current techniques. Here, we show how these lines enable a phenotypic analysis of alleles with weak or variable phenotypes, genetic mapping of novel mutations, introducing transgenes into a lethal or sterile genetic background, and separating closely linked mutations.
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Affiliation(s)
- R Scott Poethig
- Corresponding author: Department of Biology, University of Pennsylvania, Philadelphia, PA 19146, USA.
| | - William L Cullina
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19146, USA
| | - Erin Doody
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19146, USA
| | - Taré Floyd
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19146, USA
| | | | - Tieqiang Hu
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19146, USA
| | - Mingli Xu
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19146, USA,Department of Biological Sciences, University of South Carolina, Charlottesville, SC 29208, USA
| | - Jianfei Zhao
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19146, USA
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5
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Hu T, Manuela D, Hinsch V, Xu M. PICKLE associates with histone deacetylase 9 to mediate vegetative phase change in Arabidopsis. THE NEW PHYTOLOGIST 2022; 235:1070-1081. [PMID: 35460275 PMCID: PMC9324081 DOI: 10.1111/nph.18174] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 04/09/2022] [Indexed: 05/04/2023]
Abstract
The juvenile-to-adult vegetative phase change in flowering plants is mediated by a decrease in miR156 levels. Downregulation of MIR156A/MIR156C, the two major sources of miR156, is accompanied by a decrease in acetylation of histone 3 lysine 27 (H3K27ac) and an increase in trimethylation of H3K27 (H3K27me3) at MIR156A/MIR156C in Arabidopsis. Here, we show that histone deacetylase 9 (HDA9) is recruited to MIR156A/MIR156C during the juvenile phase and associates with the CHD3 chromatin remodeler PICKLE (PKL) to erase H3K27ac at MIR156A/MIR156C. H2Aub and H3K27me3 become enriched at MIR156A/MIR156C, and the recruitment of Polycomb Repressive Complex 2 (PRC2) to MIR156A/MIR156C is partially dependent on the activities of PKL and HDA9. Our results suggest that PKL associates with histone deacetylases to erase H3K27ac and promote PRC1 and PRC2 activities to mediate vegetative phase change and maintain plants in the adult phase after the phase transition.
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Affiliation(s)
- Tieqiang Hu
- Department of Biological SciencesUniversity of South CarolinaColumbiaSC29208USA
| | - Darren Manuela
- Department of Biological SciencesUniversity of South CarolinaColumbiaSC29208USA
| | - Valerie Hinsch
- Department of Biological SciencesUniversity of South CarolinaColumbiaSC29208USA
| | - Mingli Xu
- Department of Biological SciencesUniversity of South CarolinaColumbiaSC29208USA
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6
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Interaction Analysis between the Arabidopsis Transcription Repressor VAL1 and Transcription Coregulators SIN3-LIKEs (SNLs). Int J Mol Sci 2022; 23:ijms23136987. [PMID: 35805982 PMCID: PMC9266683 DOI: 10.3390/ijms23136987] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 06/16/2022] [Accepted: 06/21/2022] [Indexed: 01/19/2023] Open
Abstract
VIVIPAROUS1/ABSCISIC ACID INSENSITIVE3-LIKE1 (VAL1) encodes a DNA-binding B3 domain protein and plays essential roles in seed maturation and flowering transition by repressing genes through epigenetic silencing in Arabidopsis. SWI-INDEPENDENT3 (SIN3)-LIKEs (SNLs), which encode scaffold proteins for the assembly of histone deacetylase complexes and have six SIN3 homologues (SNL1–SNL6) in Arabidopsis thaliana, directly repress gene expression to regulate seed maturation and flowering transition. However, it remains unclear whether VAL1 and SNLs work together in repressing the expression of related genes. In this study, yeast two-hybrid and firefly luciferase complementation imaging assays revealed that VAL1 interacts with SNLs, which can be attributed to its own zinc-finger CW (conserved Cys (C) and Trp (W) residues) domain and the PAH (Paired Amphipathic Helices) domains of SNLs. Furthermore, pull-down experiments confirmed that the CW domain of VAL1 interacts with both intact protein and the PAH domains of SNLs proteins, and the co-immunoprecipitation assays also confirmed the interaction between VAL1 and SNLs. In addition, quantitative real-time PCR (qRT-PCR) analysis showed that VAL1 and SNLs were expressed in seedlings, and transient expression assays showed that VAL1 and SNLs were localized in the nucleus. Considered together, these results reveal that VAL1 physically interacts with SNLs both in vitro and in vivo, and suggest that VAL1 and SNLs may work together to repress the expression of genes related to seed maturation and flowering transition in Arabidopsis.
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7
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Dong Q, Hu B, Zhang C. microRNAs and Their Roles in Plant Development. FRONTIERS IN PLANT SCIENCE 2022; 13:824240. [PMID: 35251094 PMCID: PMC8895298 DOI: 10.3389/fpls.2022.824240] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 01/27/2022] [Indexed: 05/26/2023]
Abstract
Small RNAs are short non-coding RNAs with a length ranging between 20 and 24 nucleotides. Of these, microRNAs (miRNAs) play a distinct role in plant development. miRNAs control target gene expression at the post-transcriptional level, either through direct cleavage or inhibition of translation. miRNAs participate in nearly all the developmental processes in plants, such as juvenile-to-adult transition, shoot apical meristem development, leaf morphogenesis, floral organ formation, and flowering time determination. This review summarizes the research progress in miRNA-mediated gene regulation and its role in plant development, to provide the basis for further in-depth exploration regarding the function of miRNAs and the elucidation of the molecular mechanism underlying the interaction of miRNAs and other pathways.
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Affiliation(s)
- Qingkun Dong
- Key Laboratory of Plant Molecular Physiology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Binbin Hu
- Key Laboratory of Plant Molecular Physiology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Cui Zhang
- Key Laboratory of Plant Molecular Physiology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
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8
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Vijayanathan M, Trejo-Arellano MG, Mozgová I. Polycomb Repressive Complex 2 in Eukaryotes-An Evolutionary Perspective. EPIGENOMES 2022; 6:3. [PMID: 35076495 PMCID: PMC8788455 DOI: 10.3390/epigenomes6010003] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 01/12/2022] [Accepted: 01/12/2022] [Indexed: 12/23/2022] Open
Abstract
Polycomb repressive complex 2 (PRC2) represents a group of evolutionarily conserved multi-subunit complexes that repress gene transcription by introducing trimethylation of lysine 27 on histone 3 (H3K27me3). PRC2 activity is of key importance for cell identity specification and developmental phase transitions in animals and plants. The composition, biochemistry, and developmental function of PRC2 in animal and flowering plant model species are relatively well described. Recent evidence demonstrates the presence of PRC2 complexes in various eukaryotic supergroups, suggesting conservation of the complex and its function. Here, we provide an overview of the current understanding of PRC2-mediated repression in different representatives of eukaryotic supergroups with a focus on the green lineage. By comparison of PRC2 in different eukaryotes, we highlight the possible common and diverged features suggesting evolutionary implications and outline emerging questions and directions for future research of polycomb repression and its evolution.
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Affiliation(s)
- Mallika Vijayanathan
- Biology Centre, Institute of Plant Molecular Biology, Czech Academy of Sciences, 370 05 Ceske Budejovice, Czech Republic; (M.V.); (M.G.T.-A.)
| | - María Guadalupe Trejo-Arellano
- Biology Centre, Institute of Plant Molecular Biology, Czech Academy of Sciences, 370 05 Ceske Budejovice, Czech Republic; (M.V.); (M.G.T.-A.)
| | - Iva Mozgová
- Biology Centre, Institute of Plant Molecular Biology, Czech Academy of Sciences, 370 05 Ceske Budejovice, Czech Republic; (M.V.); (M.G.T.-A.)
- Faculty of Science, University of South Bohemia, 370 05 Ceske Budejovice, Czech Republic
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9
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Fang H, Shao Y, Wu G. Reprogramming of Histone H3 Lysine Methylation During Plant Sexual Reproduction. FRONTIERS IN PLANT SCIENCE 2021; 12:782450. [PMID: 34917115 PMCID: PMC8669150 DOI: 10.3389/fpls.2021.782450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/08/2021] [Indexed: 06/14/2023]
Abstract
Plants undergo extensive reprogramming of chromatin status during sexual reproduction, a process vital to cell specification and pluri- or totipotency establishment. As a crucial way to regulate chromatin organization and transcriptional activity, histone modification can be reprogrammed during sporogenesis, gametogenesis, and embryogenesis in flowering plants. In this review, we first introduce enzymes required for writing, recognizing, and removing methylation marks on lysine residues in histone H3 tails, and describe their differential expression patterns in reproductive tissues, then we summarize their functions in the reprogramming of H3 lysine methylation and the corresponding chromatin re-organization during sexual reproduction in Arabidopsis, and finally we discuss the molecular significance of histone reprogramming in maintaining the pluri- or totipotency of gametes and the zygote, and in establishing novel cell fates throughout the plant life cycle. Despite rapid achievements in understanding the molecular mechanism and function of the reprogramming of chromatin status in plant development, the research in this area still remains a challenge. Technological breakthroughs in cell-specific epigenomic profiling in the future will ultimately provide a solution for this challenge.
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10
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Cell division in the shoot apical meristem is a trigger for miR156 decline and vegetative phase transition in Arabidopsis. Proc Natl Acad Sci U S A 2021; 118:2115667118. [PMID: 34750273 DOI: 10.1073/pnas.2115667118] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2021] [Indexed: 11/18/2022] Open
Abstract
What determines the rate at which a multicellular organism matures is a fundamental question in biology. In plants, the decline of miR156 with age serves as an intrinsic, evolutionarily conserved timer for the juvenile-to-adult phase transition. However, the way in which age regulates miR156 abundance is poorly understood. Here, we show that the rate of decline in miR156 is correlated with developmental age rather than chronological age. Mechanistically, we found that cell division in the apical meristem is a trigger for miR156 decline. The transcriptional activity of MIR156 genes is gradually attenuated by the deposition of the repressive histone mark H3K27me3 along with cell division. Our findings thus provide a plausible explanation of why the maturation program of a multicellular organism is unidirectional and irreversible under normal growth conditions and suggest that cell quiescence is the fountain of youth in plants.
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11
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Osadchuk K, Cheng CL, Irish EE. The integration of leaf-derived signals sets the timing of vegetative phase change in maize, a process coordinated by epigenetic remodeling. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 312:111035. [PMID: 34620439 DOI: 10.1016/j.plantsci.2021.111035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/02/2021] [Accepted: 08/24/2021] [Indexed: 06/13/2023]
Abstract
After germination, the maize shoot proceeds through a series of developmental stages before flowering. The first transition occurs during the vegetative phase where the shoot matures from the juvenile to the adult phase, called vegetative phase change (VPC). In maize, both phases exhibit easily-scored morphological characteristics, facilitating the elucidation of molecular mechanisms directing the characteristic gene expression patterns and resulting physiological features of each phase. miR156 expression is high during the juvenile phase, suppressing expression of squamosa promoter binding proteins/SBP-like transcription factors and miR172. The decline in miR156 and subsequent increase in miR172 expression marks the transition into the adult phase, where miR172 represses transcripts that confer juvenile traits. Leaf-derived signals attenuate miR156 expression and thus the duration of the juvenile phase. As found in other species, VPC in maize utilizes signals that consist of hormones, stress, and sugar to direct epigenetic modifiers. In this review we identify the intersection of leaf-derived signaling with components that contribute to the epigenetic changes which may, in turn, manage the distinct global gene expression patterns of each phase. In maize, published research regarding chromatin remodeling during VPC is minimal. Therefore, we identified epigenetic regulators in the maize genome and, using published gene expression data and research from other plant species, identify VPC candidates.
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Affiliation(s)
- Krista Osadchuk
- 129 E. Jefferson Street, Department of Biology, University of Iowa, Iowa City, IA, USA
| | - Chi-Lien Cheng
- 129 E. Jefferson Street, Department of Biology, University of Iowa, Iowa City, IA, USA
| | - Erin E Irish
- 129 E. Jefferson Street, Department of Biology, University of Iowa, Iowa City, IA, USA.
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The Regulation of Plant Vegetative Phase Transition and Rejuvenation: miRNAs, a Key Regulator. EPIGENOMES 2021; 5:epigenomes5040024. [PMID: 34968248 PMCID: PMC8715473 DOI: 10.3390/epigenomes5040024] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 09/23/2021] [Accepted: 09/24/2021] [Indexed: 01/13/2023] Open
Abstract
In contrast to animals, adult organs in plants are not formed during embryogenesis but generated from meristematic cells as plants advance through development. Plant development involves a succession of different phenotypic stages and the transition between these stages is termed phase transition. Phase transitions need to be tightly regulated and coordinated to ensure they occur under optimal seasonal, environmental conditions. Polycarpic perennials transition through vegetative stages and the mature, reproductive stage many times during their lifecycles and, in both perennial and annual species, environmental factors and culturing methods can reverse the otherwise unidirectional vector of plant development. Epigenetic factors regulating gene expression in response to internal cues and external (environmental) stimuli influencing the plant’s phenotype and development have been shown to control phase transitions. How developmental and environmental cues interact to epigenetically alter gene expression and influence these transitions is not well understood, and understanding this interaction is important considering the current climate change scenarios, since epigenetic maladaptation could have catastrophic consequences for perennial plants in natural and agricultural ecosystems. Here, we review studies focusing on the epigenetic regulators of the vegetative phase change and highlight how these mechanisms might act in exogenously induced plant rejuvenation and regrowth following stress.
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13
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Post-Embryonic Phase Transitions Mediated by Polycomb Repressive Complexes in Plants. Int J Mol Sci 2021; 22:ijms22147533. [PMID: 34299153 PMCID: PMC8305008 DOI: 10.3390/ijms22147533] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/05/2021] [Accepted: 07/09/2021] [Indexed: 12/20/2022] Open
Abstract
Correct timing of developmental phase transitions is critical for the survival and fitness of plants. Developmental phase transitions in plants are partially promoted by controlling relevant genes into active or repressive status. Polycomb Repressive Complex1 (PRC1) and PRC2, originally identified in Drosophila, are essential in initiating and/or maintaining genes in repressive status to mediate developmental phase transitions. Our review summarizes mechanisms in which the embryo-to-seedling transition, the juvenile-to-adult transition, and vegetative-to-reproductive transition in plants are mediated by PRC1 and PRC2, and suggests that PRC1 could act either before or after PRC2, or that they could function independently of each other. Details of the exact components of PRC1 and PRC2 in each developmental phase transitions and how they are recruited or removed will need to be addressed in the future.
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