1
|
Závodník M, Pavlištová V, Machelová A, Lyčka M, Mozgová I, Caklová K, Dvořáčková M, Fajkus J. KU70 and CAF-1 in Arabidopsis: Divergent roles in rDNA stability and telomere homeostasis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:1922-1936. [PMID: 38493352 DOI: 10.1111/tpj.16718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 02/07/2024] [Accepted: 02/29/2024] [Indexed: 03/18/2024]
Abstract
Deficiency in chromatin assembly factor-1 (CAF-1) in plants through dysfunction of its components, FASCIATA1 and 2 (FAS1, FAS2), leads to the specific and progressive loss of rDNA and telomere repeats in plants. This loss is attributed to defective repair mechanisms for the increased DNA breaks encountered during replication, a consequence of impaired replication-dependent chromatin assembly. In this study, we explore the role of KU70 in these processes. Our findings reveal that, although the rDNA copy number is reduced in ku70 mutants when compared with wild-type plants, it is not markedly affected by diverse KU70 status in fas1 mutants. This is consistent with our previous characterisation of rDNA loss in fas mutants as a consequence part of the single-strand annealing pathway of homology-dependent repair. In stark contrast to rDNA, KU70 dysfunction fully suppresses the loss of telomeres in fas1 plants and converts telomeres to their elongated and heterogeneous state typical for ku70 plants. We conclude that the alternative telomere lengthening pathway, known to be activated in the absence of KU70, overrides progressive telomere loss due to CAF-1 dysfunction.
Collapse
Affiliation(s)
- Michal Závodník
- Mendel Centre for Plant Genomics and Proteomics, CEITEC, Masaryk University, Brno, CZ-62500, Czech Republic
- Department of Cell Biology and Radiobiology, Institute of Biophysics of the Czech Academy of Sciences, v.v.i., Brno, CZ-61265, Czech Republic
| | - Veronika Pavlištová
- Mendel Centre for Plant Genomics and Proteomics, CEITEC, Masaryk University, Brno, CZ-62500, Czech Republic
- Laboratory of Functional Genomics and Proteomics, NCBR, Faculty of Science, Masaryk University, Brno, CZ-61137, Czech Republic
| | - Adéla Machelová
- Mendel Centre for Plant Genomics and Proteomics, CEITEC, Masaryk University, Brno, CZ-62500, Czech Republic
- Laboratory of Functional Genomics and Proteomics, NCBR, Faculty of Science, Masaryk University, Brno, CZ-61137, Czech Republic
| | - Martin Lyčka
- Mendel Centre for Plant Genomics and Proteomics, CEITEC, Masaryk University, Brno, CZ-62500, Czech Republic
- Laboratory of Functional Genomics and Proteomics, NCBR, Faculty of Science, Masaryk University, Brno, CZ-61137, Czech Republic
| | - Iva Mozgová
- Biology Centre, Czech Academy of Sciences, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
- University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic
| | - Karolína Caklová
- Laboratory of Functional Genomics and Proteomics, NCBR, Faculty of Science, Masaryk University, Brno, CZ-61137, Czech Republic
| | - Martina Dvořáčková
- Mendel Centre for Plant Genomics and Proteomics, CEITEC, Masaryk University, Brno, CZ-62500, Czech Republic
- Laboratory of Functional Genomics and Proteomics, NCBR, Faculty of Science, Masaryk University, Brno, CZ-61137, Czech Republic
| | - Jiří Fajkus
- Mendel Centre for Plant Genomics and Proteomics, CEITEC, Masaryk University, Brno, CZ-62500, Czech Republic
- Department of Cell Biology and Radiobiology, Institute of Biophysics of the Czech Academy of Sciences, v.v.i., Brno, CZ-61265, Czech Republic
- Laboratory of Functional Genomics and Proteomics, NCBR, Faculty of Science, Masaryk University, Brno, CZ-61137, Czech Republic
| |
Collapse
|
2
|
Tabeta H, Gunji S, Kawade K, Ferjani A. Leaf-size control beyond transcription factors: Compensatory mechanisms. FRONTIERS IN PLANT SCIENCE 2023; 13:1024945. [PMID: 36756231 PMCID: PMC9901582 DOI: 10.3389/fpls.2022.1024945] [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: 08/22/2022] [Accepted: 12/28/2022] [Indexed: 06/18/2023]
Abstract
Plant leaves display abundant morphological richness yet grow to characteristic sizes and shapes. Beginning with a small number of undifferentiated founder cells, leaves evolve via a complex interplay of regulatory factors that ultimately influence cell proliferation and subsequent post-mitotic cell enlargement. During their development, a sequence of key events that shape leaves is both robustly executed spatiotemporally following a genomic molecular network and flexibly tuned by a variety of environmental stimuli. Decades of work on Arabidopsis thaliana have revisited the compensatory phenomena that might reflect a general and primary size-regulatory mechanism in leaves. This review focuses on key molecular and cellular events behind the organ-wide scale regulation of compensatory mechanisms. Lastly, emerging novel mechanisms of metabolic and hormonal regulation are discussed, based on recent advances in the field that have provided insights into, among other phenomena, leaf-size regulation.
Collapse
Affiliation(s)
- Hiromitsu Tabeta
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
- Department of Biology, Tokyo Gakugei University, Tokyo, Japan
- RIKEN Center for Sustainable Resource Science, Yokohama, Japan
| | - Shizuka Gunji
- Department of Biology, Tokyo Gakugei University, Tokyo, Japan
| | - Kensuke Kawade
- RIKEN Center for Sustainable Resource Science, Yokohama, Japan
- National Institute for Basic Biology, Okazaki, Japan
- Department of Basic Biology, School of Life Science, Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei University, Tokyo, Japan
| |
Collapse
|
3
|
Eshel G, Duppen N, Wang G, Oh D, Kazachkova Y, Herzyk P, Amtmann A, Gordon M, Chalifa‐Caspi V, Oscar MA, Bar‐David S, Marshall‐Colon A, Dassanayake M, Barak S. Positive selection and heat-response transcriptomes reveal adaptive features of the Brassicaceae desert model, Anastatica hierochuntica. THE NEW PHYTOLOGIST 2022; 236:1006-1026. [PMID: 35909295 PMCID: PMC9804903 DOI: 10.1111/nph.18411] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
Plant adaptation to a desert environment and its endemic heat stress is poorly understood at the molecular level. The naturally heat-tolerant Brassicaceae species Anastatica hierochuntica is an ideal extremophyte model to identify genetic adaptations that have evolved to allow plants to tolerate heat stress and thrive in deserts. We generated an A. hierochuntica reference transcriptome and identified extremophyte adaptations by comparing Arabidopsis thaliana and A. hierochuntica transcriptome responses to heat, and detecting positively selected genes in A. hierochuntica. The two species exhibit similar transcriptome adjustment in response to heat and the A. hierochuntica transcriptome does not exist in a constitutive heat 'stress-ready' state. Furthermore, the A. hierochuntica global transcriptome as well as heat-responsive orthologs, display a lower basal and higher heat-induced expression than in A. thaliana. Genes positively selected in multiple extremophytes are associated with stomatal opening, nutrient acquisition, and UV-B induced DNA repair while those unique to A. hierochuntica are consistent with its photoperiod-insensitive, early-flowering phenotype. We suggest that evolution of a flexible transcriptome confers the ability to quickly react to extreme diurnal temperature fluctuations characteristic of a desert environment while positive selection of genes involved in stress tolerance and early flowering could facilitate an opportunistic desert lifestyle.
Collapse
Affiliation(s)
- Gil Eshel
- Albert Katz International School for Desert StudiesBen‐Gurion University of the NegevSde Boqer CampusMidreshet Ben‐Gurion8499000Israel
| | - Nick Duppen
- Albert Katz International School for Desert StudiesBen‐Gurion University of the NegevSde Boqer CampusMidreshet Ben‐Gurion8499000Israel
| | - Guannan Wang
- Department of Biological SciencesLouisiana State UniversityBaton RougeLA70803USA
| | - Dong‐Ha Oh
- Department of Biological SciencesLouisiana State UniversityBaton RougeLA70803USA
| | - Yana Kazachkova
- Albert Katz International School for Desert StudiesBen‐Gurion University of the NegevSde Boqer CampusMidreshet Ben‐Gurion8499000Israel
| | - Pawel Herzyk
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life SciencesUniversity of GlasgowGlasgowG12 8QQUK
| | - Anna Amtmann
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life SciencesUniversity of GlasgowGlasgowG12 8QQUK
| | - Michal Gordon
- Bioinformatics Core Facility, The National Institute for Biotechnology in the NegevBen‐Gurion University of the NegevBeer‐Sheva8410501Israel
| | - Vered Chalifa‐Caspi
- Bioinformatics Core Facility, The National Institute for Biotechnology in the NegevBen‐Gurion University of the NegevBeer‐Sheva8410501Israel
| | - Michelle Arland Oscar
- Blaustein Center for Scientific CooperationBen‐Gurion University of the NegevSde Boqer CampusMidreshet Ben‐Gurion8499000Israel
| | - Shirli Bar‐David
- Mitrani Department of Desert Ecology, Jacob Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevSde Boqer CampusMidreshet Ben‐Gurion8499000Israel
| | - Amy Marshall‐Colon
- Department of Plant BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIL61801USA
| | - Maheshi Dassanayake
- Department of Biological SciencesLouisiana State UniversityBaton RougeLA70803USA
| | - Simon Barak
- French Associates' Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert ResearchBen‐Gurion University of the NegevSde Boqer CampusMidreshet Ben‐Gurion8499000Israel
| |
Collapse
|
4
|
Nakayama H, Koga H, Long Y, Hamant O, Ferjani A. Looking beyond the gene network - metabolic and mechanical cell drivers of leaf morphogenesis. J Cell Sci 2022; 135:275072. [PMID: 35438169 DOI: 10.1242/jcs.259611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The above-ground organs in plants display a rich diversity, yet they grow to characteristic sizes and shapes. Organ morphogenesis progresses through a sequence of key events, which are robustly executed spatiotemporally as an emerging property of intrinsic molecular networks while adapting to various environmental cues. This Review focuses on the multiscale control of leaf morphogenesis. Beyond the list of known genetic determinants underlying leaf growth and shape, we focus instead on the emerging novel mechanisms of metabolic and biomechanical regulations that coordinate plant cell growth non-cell-autonomously. This reveals how metabolism and mechanics are not solely passive outcomes of genetic regulation but play instructive roles in leaf morphogenesis. Such an integrative view also extends to fluctuating environmental cues and evolutionary adaptation. This synthesis calls for a more balanced view on morphogenesis, where shapes are considered from the standpoints of geometry, genetics, energy and mechanics, and as emerging properties of the cellular expression of these different properties.
Collapse
Affiliation(s)
- Hokuto Nakayama
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 113-0033 Tokyo, Japan
| | - Hiroyuki Koga
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 113-0033 Tokyo, Japan
| | - Yuchen Long
- Department of Biological Sciences, The National University of Singapore, Singapore 117543, Singapore
| | - Olivier Hamant
- Laboratoire de Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, 69007 Lyon, France
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei University, 184-8501 Tokyo, Japan
| |
Collapse
|
5
|
Pedroza-Garcia JA, Xiang Y, De Veylder L. Cell cycle checkpoint control in response to DNA damage by environmental stresses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:490-507. [PMID: 34741364 DOI: 10.1111/tpj.15567] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/26/2021] [Accepted: 11/01/2021] [Indexed: 06/13/2023]
Abstract
Being sessile organisms, plants are ubiquitously exposed to stresses that can affect the DNA replication process or cause DNA damage. To cope with these problems, plants utilize DNA damage response (DDR) pathways, consisting of both highly conserved and plant-specific elements. As a part of this DDR, cell cycle checkpoint control mechanisms either pause the cell cycle, to allow DNA repair, or lead cells into differentiation or programmed cell death, to prevent the transmission of DNA errors in the organism through mitosis or to its offspring via meiosis. The two major DDR cell cycle checkpoints control either the replication process or the G2/M transition. The latter is largely overseen by the plant-specific SOG1 transcription factor, which drives the activity of cyclin-dependent kinase inhibitors and MYB3R proteins, which are rate limiting for the G2/M transition. By contrast, the replication checkpoint is controlled by different players, including the conserved kinase WEE1 and likely the transcriptional repressor RBR1. These checkpoint mechanisms are called upon during developmental processes, in retrograde signaling pathways, and in response to biotic and abiotic stresses, including metal toxicity, cold, salinity, and phosphate deficiency. Additionally, the recent expansion of research from Arabidopsis to other model plants has revealed species-specific aspects of the DDR. Overall, it is becoming evidently clear that the DNA damage checkpoint mechanisms represent an important aspect of the adaptation of plants to a changing environment, hence gaining more knowledge about this topic might be helpful to increase the resilience of plants to climate change.
Collapse
Affiliation(s)
- José Antonio Pedroza-Garcia
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent, B-9052, Belgium
| | - Yanli Xiang
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent, B-9052, Belgium
| | - Lieven De Veylder
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- Center for Plant Systems Biology, VIB, Ghent, B-9052, Belgium
| |
Collapse
|
6
|
Tulin F. Buying time: FASCIATA1 deficiency rescues wee1 plants from replication stress by delaying mitosis. PLANT PHYSIOLOGY 2021; 186:1762-1764. [PMID: 34618115 PMCID: PMC8331142 DOI: 10.1093/plphys/kiab256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 05/25/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Frej Tulin
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| |
Collapse
|
7
|
Eekhout T, Dvorackova M, Pedroza Garcia JA, Nespor Dadejova M, Kalhorzadeh P, Van den Daele H, Vercauteren I, Fajkus J, De Veylder L. G2/M-checkpoint activation in fasciata1 rescues an aberrant S-phase checkpoint but causes genome instability. PLANT PHYSIOLOGY 2021; 186:1893-1907. [PMID: 34618100 PMCID: PMC8331141 DOI: 10.1093/plphys/kiab201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 04/05/2021] [Indexed: 05/13/2023]
Abstract
The WEE1 and ATM AND RAD3-RELATED (ATR) kinases are important regulators of the plant intra-S-phase checkpoint; consequently, WEE1KO and ATRKO roots are hypersensitive to replication-inhibitory drugs. Here, we report on a loss-of-function mutant allele of the FASCIATA1 (FAS1) subunit of the chromatin assembly factor 1 (CAF-1) complex that suppresses the phenotype of WEE1- or ATR-deficient Arabidopsis (Arabidopsis thaliana) plants. We demonstrate that lack of FAS1 activity results in the activation of an ATAXIA TELANGIECTASIA MUTATED (ATM)- and SUPPRESSOR OF GAMMA-RESPONSE 1 (SOG1)-mediated G2/M-arrest that renders the ATR and WEE1 checkpoint regulators redundant. This ATM activation accounts for the telomere erosion and loss of ribosomal DNA that are described for fas1 plants. Knocking out SOG1 in the fas1 wee1 background restores replication stress sensitivity, demonstrating that SOG1 is an important secondary checkpoint regulator in plants that fail to activate the intra-S-phase checkpoint.
Collapse
Affiliation(s)
- Thomas Eekhout
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Gent, Belgium
| | - Martina Dvorackova
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, CZ-62500 Brno, Czech Republic
| | - José Antonio Pedroza Garcia
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Gent, Belgium
| | - Martina Nespor Dadejova
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, CZ-62500 Brno, Czech Republic
| | - Pooneh Kalhorzadeh
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Gent, Belgium
| | - Hilde Van den Daele
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Gent, Belgium
| | - Ilse Vercauteren
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Gent, Belgium
| | - Jiri Fajkus
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, CZ-62500 Brno, Czech Republic
| | - Lieven De Veylder
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Gent, Belgium
| |
Collapse
|
8
|
Kolářová K, Nešpor Dadejová M, Loja T, Lochmanová G, Sýkorová E, Dvořáčková M. Disruption of NAP1 genes in Arabidopsis thaliana suppresses the fas1 mutant phenotype, enhances genome stability and changes chromatin compaction. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:56-73. [PMID: 33368779 DOI: 10.1111/tpj.15145] [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: 09/12/2020] [Revised: 11/21/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
Histone chaperones mediate the assembly and disassembly of nucleosomes and participate in essentially all DNA-dependent cellular processes. In Arabidopsis thaliana, loss-of-function of FAS1 or FAS2 subunits of the H3-H4 histone chaperone complex CHROMATIN ASSEMBLY FACTOR 1 (CAF-1) has a dramatic effect on plant morphology, growth and overall fitness. CAF-1 dysfunction can lead to altered chromatin compaction, systematic loss of repetitive elements or increased DNA damage, clearly demonstrating its severity. How chromatin composition is maintained without functional CAF-1 remains elusive. Here we show that disruption of the H2A-H2B histone chaperone NUCLEOSOME ASSEMBLY PROTEIN 1 (NAP1) suppresses the FAS1 loss-of-function phenotype. The quadruple mutant fas1 nap1;1 nap1;2 nap1;3 shows wild-type growth, decreased sensitivity to genotoxic stress and suppression of telomere and 45S rDNA loss. Chromatin of fas1 nap1;1 nap1;2 nap1;3 plants is less accessible to micrococcal nuclease and the nuclear H3.1 and H3.3 histone pools change compared to fas1. Consistently, association between NAP1 and H3 occurs in the cytoplasm and nucleus in vivo in protoplasts. Altogether we show that NAP1 proteins play an essential role in DNA repair in fas1, which is coupled to nucleosome assembly through modulation of H3 levels in the nucleus.
Collapse
Affiliation(s)
- Karolína Kolářová
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kotlářská 2, Brno, CZ-61137, Czech Republic
- Molecular Cytology and Cytometry, Institute of Biophysics of the Czech Academy of Sciences, v.v.i., Královopolská 135, Brno, CZ-61265, Czech Republic
| | - Martina Nešpor Dadejová
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology/Masaryk University, Kamenice 5, Brno, CZ-62500, Czech Republic
| | - Tomáš Loja
- Centre for Molecular Medicine, Central European Institute of Technology/Masaryk University, Kamenice 5, Brno, CZ-62500, Czech Republic
| | - Gabriela Lochmanová
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology/Masaryk University, Kamenice 5, Brno, CZ-62500, Czech Republic
| | - Eva Sýkorová
- Molecular Cytology and Cytometry, Institute of Biophysics of the Czech Academy of Sciences, v.v.i., Královopolská 135, Brno, CZ-61265, Czech Republic
| | - Martina Dvořáčková
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology/Masaryk University, Kamenice 5, Brno, CZ-62500, Czech Republic
| |
Collapse
|
9
|
Fujikura U, Ezaki K, Horiguchi G, Seo M, Kanno Y, Kamiya Y, Lenhard M, Tsukaya H. Suppression of class I compensated cell enlargement by xs2 mutation is mediated by salicylic acid signaling. PLoS Genet 2020; 16:e1008873. [PMID: 32584819 PMCID: PMC7343186 DOI: 10.1371/journal.pgen.1008873] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 07/08/2020] [Accepted: 05/20/2020] [Indexed: 11/18/2022] Open
Abstract
The regulation of leaf size has been studied for decades. Enhancement of post-mitotic cell expansion triggered by impaired cell proliferation in Arabidopsis is an important process for leaf size regulation, and is known as compensation. This suggests a key interaction between cell proliferation and cell expansion during leaf development. Several studies have highlighted the impact of this integration mechanism on leaf size determination; however, the molecular basis of compensation remains largely unknown. Previously, we identified extra-small sisters (xs) mutants which can suppress compensated cell enlargement (CCE) via a specific defect in cell expansion within the compensation-exhibiting mutant, angustifolia3 (an3). Here we revealed that one of the xs mutants, namely xs2, can suppress CCE not only in an3 but also in other compensation-exhibiting mutants erecta (er) and fugu2. Molecular cloning of XS2 identified a deleterious mutation in CATION CALCIUM EXCHANGER 4 (CCX4). Phytohormone measurement and expression analysis revealed that xs2 shows hyper activation of the salicylic acid (SA) response pathway, where activation of SA response can suppress CCE in compensation mutants. All together, these results highlight the regulatory connection which coordinates compensation and SA response. Leaves are determinate organ and size of leaves are determined by intrinsic and extrinsic cues. Cell proliferation and post-mitotic cell expansion should be coordinated during leaf morphogenesis to develop appropriate size depending on its developmental programs. Recent studies highlighted the existence of integrated mechanism which coordinates cell proliferation and cell expansion during leaf development. Compensation, which is enhanced post-mitotic cell expansion accompanied by a significant decrease in cell number during leaf organogenesis, is one of the clues for such coordination. However, the molecular mechanisms linking cell proliferation and cell expansion are still poorly understood. Previously, we reported extra-small sisters 2 (xs2) mutation caused specific defect in cell expansion and it suppressed increased post-mitotic cell enlargement in angustifolia3 (an3) mutant, which exhibits typical compensation. Here we identify the affected gene of xs2 mutant encodes a member of cation calcium exchanger which is believed to be involved in cation homeostasis within cells. Loss of function of this protein causes hyper accumulation of salicylic acid (SA) and increased expression of pathogen related genes. Physiological and genetic studies revealed activated SA signal transduction reduced cell size. It suppressed post-mitotic cell expansion in several compensation mutants not only an3 but partially suppressed in another type of compensation mutant which increases size of mitotic cells. This finding suggests post-mitotic cell expansion pathway is regulated in common by SA-dependent signaling and by compensation signaling during leaf development.
Collapse
Affiliation(s)
- Ushio Fujikura
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Japan
- * E-mail:
| | - Kazune Ezaki
- Graduate School of Science, The University of Tokyo, Japan
| | - Gorou Horiguchi
- Department of Life Science, College of Science, Rikkyo University, Japan
| | - Mitsunori Seo
- RIKEN Center for Sustainable Resource Science, Japan
| | - Yuri Kanno
- RIKEN Center for Sustainable Resource Science, Japan
| | - Yuji Kamiya
- RIKEN Center for Sustainable Resource Science, Japan
| | - Michael Lenhard
- Institut für Biochemie und Biologie, Universität Potsdam, Potsdam-Golm, Germany
| | - Hirokazu Tsukaya
- Graduate School of Science, The University of Tokyo, Japan
- Okazaki Institute for Integrative Bioscience, Japan
| |
Collapse
|
10
|
Maulión E, Gomez MS, Bustamante CA, Casati P. AtCAF-1 mutants show different DNA damage responses after ultraviolet-B than those activated by other genotoxic agents in leaves. PLANT, CELL & ENVIRONMENT 2019; 42:2730-2745. [PMID: 31145828 DOI: 10.1111/pce.13596] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 05/21/2019] [Accepted: 05/25/2019] [Indexed: 05/27/2023]
Abstract
Chromatin assembly factor-1 (CAF-1) is a histone H3/H4 chaperone that participates in DNA and chromatin interaction processes. In this manuscript, we show that organs from CAF-1 deficient plants respond differently to ultraviolet-B (UV-B) radiation than to other genotoxic stresses. For example, CAF-1 deficient leaves tolerate better UV-B radiation, showing lower cyclobutane pyrimidine dimer (CPD) accumulation, lower inhibition of cell proliferation, increased cell wall thickness, UV-B absorbing compounds, and ploidy levels, whereas previous data from different groups have shown that CAF-1 mutants show shortening of telomeres, loss of 45S rDNA, and increased homologous recombination, phenotypes associated to DNA breaks. Interestingly, CAF-1 deficient roots show increased inhibition of primary root elongation, with decreased meristem size due to a higher inhibition of cell proliferation after UV-B exposure. The decrease in root meristem size in CAF-1 mutants is a consequence of defects in programmed cell death after UV-B exposure. Together, we provide evidence demonstrating that root and shoot meristematic cells may have distinct protection mechanisms against CPD accumulation by UV-B, which may be linked with different functions of the CAF-1 complex in these different organs.
Collapse
Affiliation(s)
- Evangelina Maulión
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Rosario, Argentina
| | - María Sol Gomez
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Rosario, Argentina
| | - Claudia Anabel Bustamante
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Rosario, Argentina
| | - Paula Casati
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Rosario, Argentina
| |
Collapse
|
11
|
Tsukaya H. Has the impact of endoreduplication on cell size been overestimated? THE NEW PHYTOLOGIST 2019; 223:11-15. [PMID: 30854661 DOI: 10.1111/nph.15781] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Accepted: 02/28/2019] [Indexed: 06/09/2023]
Affiliation(s)
- Hirokazu Tsukaya
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan
- ExCELLS, National Institutes of Natural Sciences, Okazaki, 444-8787, Japan
| |
Collapse
|
12
|
Abnormal leaf development of rpt5a mutant under zinc deficiency reveals important role of DNA damage alleviation for normal leaf development. Sci Rep 2019; 9:9369. [PMID: 31249317 PMCID: PMC6597565 DOI: 10.1038/s41598-019-44789-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 04/27/2019] [Indexed: 12/22/2022] Open
Abstract
Leaf development in plants, including dorsoventral (adaxial–abaxial) patterning, is tightly regulated. The involvement of several subunits of the 26S proteasome in adaxial–abaxial polarity establishment has been reported. In the present study, we revealed that in Arabidopsis thaliana, a mutation in RPT5A, a subunit of 26S proteasome, causes abnormally narrow true leaves under zinc deficiency. mRNA accumulations of DNA damage marker genes in leaves were elevated by zinc deficiency. PARP2, a single-strand break (SSB) inducible gene, was more strongly induced by zinc deficiency in rpt5a mutants compared with the wild type. A comet assay indicated that SSB is enhanced in mutants grown under the zinc deficiency condition. These results suggest that SSB accumulation is accompanied by abnormal leaf development. To test if DNA damage is a sole cause of abnormal leaf development, we treated the wild type grown under normal zinc conditions with zeocin, a DNA damage-inducing reagent, and found that narrow leaves developed, suggesting that DNA damage is sufficient to induce the development of abnormally narrow leaves. Taken together with the observation of the abnormal leaf morphology of our mutant plant under zinc deficiency, we demonstrated that the alleviation of DNA damage is important for normal leaf development.
Collapse
|
13
|
Montané MH, Menand B. TOR inhibitors: from mammalian outcomes to pharmacogenetics in plants and algae. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2297-2312. [PMID: 30773593 DOI: 10.1093/jxb/erz053] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 02/05/2019] [Indexed: 05/19/2023]
Abstract
Target of rapamycin (TOR) is a conserved eukaryotic phosphatidylinositol 3-kinase-related kinase that regulates growth and metabolism in response to environment in plants and algae. The study of the plant and algal TOR pathway has largely depended on TOR inhibitors first developed for non-photosynthetic eukaryotes. In animals and yeast, fundamental work on the TOR pathway has benefited from the allosteric TOR inhibitor rapamycin and more recently from ATP-competitive TOR inhibitors (asTORis) that circumvent the limitations of rapamycin. The asTORis, developed for medical application, inhibit TOR complex 1 (TORC1) more efficiently than rapamycin and also inhibit rapamycin-resistant TORCs. This review presents knowledge on TOR inhibitors from the mammalian field and underlines important considerations for plant and algal biologists. It discusses the use of rapamycin and asTORis in plants and algae and concludes with guidelines for physiological studies and genetic screens with TOR inhibitors.
Collapse
Affiliation(s)
- Marie-Hélène Montané
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de génétique et biophysique des plantes, Marseille, F-13009, France
| | - Benoît Menand
- Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de génétique et biophysique des plantes, Marseille, F-13009, France
| |
Collapse
|
14
|
Kim JH, Ryu TH, Lee SS, Lee S, Chung BY. Ionizing radiation manifesting DNA damage response in plants: An overview of DNA damage signaling and repair mechanisms in plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 278:44-53. [PMID: 30471728 DOI: 10.1016/j.plantsci.2018.10.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 09/30/2018] [Accepted: 10/16/2018] [Indexed: 05/23/2023]
Abstract
Plants orchestrate various DNA damage responses (DDRs) to overcome the deleterious impacts of genotoxic agents on genetic materials. Ionizing radiation (IR) is widely used as a potent genotoxic agent in plant DDR research as well as plant breeding and quarantine services for commercial uses. This review aimed to highlight the recent advances in cellular and phenotypic DDRs, especially those induced by IR. Various physicochemical genotoxic agents damage DNA directly or indirectly by inhibiting DNA replication. Among them, IR-induced DDRs are considerably more complicated. Many aspects of such DDRs and their initial transcriptomes are closely related to oxidative stress response. Although many key components of DDR signaling have been characterized in plants, DDRs in plant cells are not understood in detail to allow comparison with those in yeast and mammalian cells. Recent studies have revealed plant DDR signaling pathways including the key regulator SOG1. The SOG1 and its upstream key components ATM and ATR could be functionally characterized by analyzing their knockout DDR phenotypes after exposure to IR. Considering the potent genotoxicity of IR and its various DDR phenotypes, IR-induced DDR studies should help to establish an integrated model for plant DDR signaling pathways by revealing the unknown key components of various DDRs in plants.
Collapse
Affiliation(s)
- Jin-Hong Kim
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea; Department of Radiation Biotechnology and Applied Radioisotope Science, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea.
| | - Tae Ho Ryu
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
| | - Seung Sik Lee
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea; Department of Radiation Biotechnology and Applied Radioisotope Science, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea
| | - Sungbeom Lee
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea; Department of Radiation Biotechnology and Applied Radioisotope Science, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea
| | - Byung Yeoup Chung
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
| |
Collapse
|
15
|
Hasegawa J, Sakamoto T, Fujimoto S, Yamashita T, Suzuki T, Matsunaga S. Auxin decreases chromatin accessibility through the TIR1/AFBs auxin signaling pathway in proliferative cells. Sci Rep 2018; 8:7773. [PMID: 29773913 PMCID: PMC5958073 DOI: 10.1038/s41598-018-25963-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 05/02/2018] [Indexed: 11/09/2022] Open
Abstract
Chromatin accessibility is closely associated with chromatin functions such as gene expression, DNA replication, and maintenance of DNA integrity. However, the relationship between chromatin accessibility and plant hormone signaling has remained elusive. Here, based on the correlation between chromatin accessibility and DNA damage, we used the sensitivity to DNA double strand breaks (DSBs) as an indicator of chromatin accessibility and demonstrated that auxin regulates chromatin accessibility through the TIR1/AFBs signaling pathway in proliferative cells. Treatment of proliferating plant cells with an inhibitor of the TIR1/AFBs auxin signaling pathway, PEO-IAA, caused chromatin loosening, indicating that auxin signaling functions to decrease chromatin accessibility. In addition, a transcriptome analysis revealed that several histone H4 genes and a histone chaperone gene, FAS1, are positively regulated through the TIR1/AFBs signaling pathway, suggesting that auxin plays a role in promoting nucleosome assembly. Analysis of the fas1 mutant of Arabidopsis thaliana confirmed that FAS1 is required for the auxin-dependent decrease in chromatin accessibility. These results suggest that the positive regulation of chromatin-related genes mediated by the TIR1/AFBs auxin signaling pathway enhances nucleosome assembly, resulting in decreased chromatin accessibility in proliferative cells.
Collapse
Affiliation(s)
- Junko Hasegawa
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan
| | - Takuya Sakamoto
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan
| | - Satoru Fujimoto
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan
| | - Tomoe Yamashita
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan
| | - Takamasa Suzuki
- College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi, 487-8501, Japan
| | - Sachihiro Matsunaga
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan.
| |
Collapse
|
16
|
Nikitaki Z, Holá M, Donà M, Pavlopoulou A, Michalopoulos I, Angelis KJ, Georgakilas AG, Macovei A, Balestrazzi A. Integrating plant and animal biology for the search of novel DNA damage biomarkers. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2018; 775:21-38. [DOI: 10.1016/j.mrrev.2018.01.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 01/08/2018] [Accepted: 01/16/2018] [Indexed: 12/11/2022]
|
17
|
Gázquez A, Beemster GTS. What determines organ size differences between species? A meta-analysis of the cellular basis. THE NEW PHYTOLOGIST 2017; 215:299-308. [PMID: 28440558 DOI: 10.1111/nph.14573] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 03/13/2017] [Indexed: 05/23/2023]
Abstract
Little is known about how the characteristic differences in organ size between species are regulated. At the cellular level, the size of an organ is strictly regulated by cell division and expansion during its development. We performed a meta-analysis of the growth parameters of roots, and Graminae and eudicotyledonous leaves, to address the question of how quantitative variation in these two processes contributes to size differences across a range of species. We extracted or derived cellular parameters from published kinematic growth analyses. These data were subjected to linear regression analyses to identify the parameters that determine differences in organ growth. Our results demonstrate that, across all species and organs, similar conclusions can be made: cell number rather than cell size determines the final size of plant organs; cell number is determined by meristem size rather than the rate at which cells divide; cells that are small when leaving the meristem compensate by expanding for longer; mature cell size is primarily determined by the duration of cell expansion. These results identify the regulation of the transition from cell division to expansion as the key cellular mechanism targeted by the evolution of organ size.
Collapse
Affiliation(s)
- Ayelén Gázquez
- Laboratory for Integrated Molecular Plant Physiology Research (IMPRES), Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
- Laboratorio de Fisiología de Estrés Abiótico en Plantas, Unidad de Biotecnología 1, IIB-INTECH - CONICET - UNSAM, Chascomús, Argentina
| | - Gerrit T S Beemster
- Laboratory for Integrated Molecular Plant Physiology Research (IMPRES), Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
| |
Collapse
|
18
|
Ma H, Song T, Wang T, Wang S. Influence of Human p53 on Plant Development. PLoS One 2016; 11:e0162840. [PMID: 27648563 PMCID: PMC5029891 DOI: 10.1371/journal.pone.0162840] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 08/29/2016] [Indexed: 11/19/2022] Open
Abstract
Mammalian p53 is a super tumor suppressor and plays a key role in guarding genome from DNA damage. However, p53 has not been found in plants which do not bear cancer although they constantly expose to ionizing radiation of ultraviolet light. Here we introduced p53 into the model plant Arabidopsis and examined p53-conferred phenotype in plant. Most strikingly, p53 caused early senescence and fasciation. In plants, fasciation has been shown as a result of the elevated homologous DNA recombination. Consistently, a reporter with overlapping segments of the GUS gene (1445) showed that the frequency of homologous recombination was highly induced in p53-transgenic plants. In contrast to p53, SUPPRESSOR OF NPR1-1 INDUCIBLE 1 (SNI1), as a negative regulator of homologous recombination in plants, is not present in mammals. Comet assay and clonogenic survival assay demonstrated that SNI1 inhibited DNA damage repair caused by either ionizing radiation or hydroxyurea in human osteosarcoma U2OS cancer cells. RAD51D is a recombinase in homologous recombination and functions downstream of SNI1 in plants. Interestingly, p53 rendered the sni1 mutants madly branching of inflorescence, a phenotype of fasciation, whereas rad51d mutant fully suppressed the p53-induced phenotype, indicating that human p53 action in plant is mediated by the SNI1-RAD51D signaling pathway. The reciprocal species-swap tests of p53 and SNI1 in human and Arabidopsis manifest that these species-specific proteins play a common role in homologous recombination across kingdoms of animals and plants.
Collapse
Affiliation(s)
- Huimin Ma
- Development Center of Plant Germplasm Resources, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Teng Song
- Development Center of Plant Germplasm Resources, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Tianhua Wang
- Development Center of Plant Germplasm Resources, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Shui Wang
- Development Center of Plant Germplasm Resources, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai 200234, China
- * E-mail:
| |
Collapse
|
19
|
Abstract
Because the genome stores all genetic information required for growth and development, it is of pivotal importance to maintain DNA integrity, especially during cell division, when the genome is prone to replication errors and damage. Although over the last two decades it has become evident that the basic cell cycle toolbox of plants shares several similarities with those of fungi and mammals, plants appear to have evolved a set of distinct checkpoint regulators in response to different types of DNA stress. This might be a consequence of plants' sessile lifestyle, which exposes them to a set of unique DNA damage-inducing conditions. In this review, we highlight the types of DNA stress that plants typically experience and describe the plant-specific molecular mechanisms that control cell division in response to these stresses.
Collapse
Affiliation(s)
- Zhubing Hu
- Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium
| | - Toon Cools
- Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium
| | | |
Collapse
|
20
|
Katano M, Takahashi K, Hirano T, Kazama Y, Abe T, Tsukaya H, Ferjani A. Suppressor Screen and Phenotype Analyses Revealed an Emerging Role of the Monofunctional Peroxisomal Enoyl-CoA Hydratase 2 in Compensated Cell Enlargement. FRONTIERS IN PLANT SCIENCE 2016; 7:132. [PMID: 26925070 PMCID: PMC4756126 DOI: 10.3389/fpls.2016.00132] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 01/25/2016] [Indexed: 05/02/2023]
Abstract
Efficient use of seed nutrient reserves is crucial for germination and establishment of plant seedlings. Mobilizing seed oil reserves in Arabidopsis involves β-oxidation, the glyoxylate cycle, and gluconeogenesis, which provide essential energy and the carbon skeletons needed to sustain seedling growth until photoautotrophy is acquired. We demonstrated that H(+)-PPase activity is required for gluconeogenesis. Lack of H(+)-PPase in fugu5 mutants increases cytosolic pyrophosphate (PPi) levels, which partially reduces sucrose synthesis de novo and inhibits cell division. In contrast, post-mitotic cell expansion in cotyledons was unusually enhanced, a phenotype called compensation. Therefore, it appears that PPi inhibits several cellular functions, including cell cycling, to trigger compensated cell enlargement (CCE). Here, we mutagenized fugu5-1 seeds with (12)C(6+) heavy-ion irradiation and screened mutations that restrain CCE to gain insight into the genetic pathway(s) involved in CCE. We isolated A#3-1, in which cell size was severely reduced, but cell number remained similar to that of original fugu5-1. Moreover, cell number decreased in A#3-1 single mutant (A#3-1sm), similar to that of fugu5-1, but cell size was almost equal to that of the wild type. Surprisingly, A#3-1 mutation did not affect CCE in other compensation exhibiting mutant backgrounds, such as an3-4 and fugu2-1/fas1-6. Subsequent map-based cloning combined with genome sequencing and HRM curve analysis identified enoyl-CoA hydratase 2 (ECH2) as the causal gene of A#3-1. The above phenotypes were consistently observed in the ech2-1 allele and supplying sucrose restored the morphological and cellular phenotypes in fugu5-1, ech2-1, A#3-1sm, fugu5-1 ech2-1, and A#3-1; fugu5-1. Taken together, these results suggest that defects in either H(+)-PPase or ECH2 compromise cell proliferation due to defects in mobilizing seed storage lipids. In contrast, ECH2 alone likely promotes CCE during the post-mitotic cell expansion stage of cotyledon development, probably by converting indolebutyric acid to indole acetic acid.
Collapse
Affiliation(s)
- Mana Katano
- Department of Biology, Tokyo Gakugei UniversityTokyo, Japan
| | | | - Tomonari Hirano
- Department of Biochemistry and Applied Biosciences, Miyazaki UniversityMiyazaki, Japan
| | | | | | - Hirokazu Tsukaya
- Department of Biological Sciences, Graduate School of Science, University of TokyoTokyo, Japan
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural SciencesOkazaki, Japan
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei UniversityTokyo, Japan
- *Correspondence: Ali Ferjani,
| |
Collapse
|
21
|
A Decrease in Ambient Temperature Induces Post-Mitotic Enlargement of Palisade Cells in North American Lake Cress. PLoS One 2015; 10:e0141247. [PMID: 26569502 PMCID: PMC4646676 DOI: 10.1371/journal.pone.0141247] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 10/05/2015] [Indexed: 02/06/2023] Open
Abstract
In order to maintain organs and structures at their appropriate sizes, multicellular organisms orchestrate cell proliferation and post-mitotic cell expansion during morphogenesis. Recent studies using Arabidopsis leaves have shown that compensation, which is defined as post-mitotic cell expansion induced by a decrease in the number of cells during lateral organ development, is one example of such orchestration. Some of the basic molecular mechanisms underlying compensation have been revealed by genetic and chimeric analyses. However, to date, compensation had been observed only in mutants, transgenics, and γ-ray–treated plants, and it was unclear whether it occurs in plants under natural conditions. Here, we illustrate that a shift in ambient temperature could induce compensation in Rorippa aquatica (Brassicaceae), a semi-aquatic plant found in North America. The results suggest that compensation is a universal phenomenon among angiosperms and that the mechanism underlying compensation is shared, in part, between Arabidopsis and R. aquatica.
Collapse
|
22
|
Mozgová I, Wildhaber T, Liu Q, Abou-Mansour E, L'Haridon F, Métraux JP, Gruissem W, Hofius D, Hennig L. Chromatin assembly factor CAF-1 represses priming of plant defence response genes. NATURE PLANTS 2015; 1:15127. [PMID: 27250680 DOI: 10.1038/nplants.2015.127] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 08/03/2015] [Indexed: 05/21/2023]
Abstract
Plants have evolved efficient defence systems against pathogens that often rely on specific transcriptional responses. Priming is part of the defence syndrome, by establishing a hypersensitive state of defence genes such as after a first encounter with a pathogen. Because activation of defence responses has a fitness cost, priming must be tightly controlled to prevent spurious activation of defence. However, mechanisms that repress defence gene priming are poorly understood. Here, we show that the histone chaperone CAF-1 is required to establish a repressed chromatin state at defence genes. Absence of CAF-1 results in spurious activation of a salicylic acid-dependent pathogen defence response in plants grown under non-sterile conditions. Chromatin at defence response genes in CAF-1 mutants under non-inductive (sterile) conditions is marked by low nucleosome occupancy and high H3K4me3 at transcription start sites, resembling chromatin in primed wild-type plants. We conclude that CAF-1-mediated chromatin assembly prevents the establishment of a primed state that may under standard non-sterile growth conditions result in spurious activation of SA-dependent defence responses and consequential reduction of plant vigour.
Collapse
Affiliation(s)
- Iva Mozgová
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-75007, Sweden
| | - Thomas Wildhaber
- Department of Biology and Zurich-Basel Plant Science Center, ETH Zurich, Zurich CH-8092, Switzerland
| | - Qinsong Liu
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-75007, Sweden
| | - Eliane Abou-Mansour
- Department of Biology, University of Fribourg, Ch. du Musée 10, Fribourg 1700, Switzerland
| | - Floriane L'Haridon
- Department of Biology, University of Fribourg, Ch. du Musée 10, Fribourg 1700, Switzerland
| | - Jean-Pierre Métraux
- Department of Biology, University of Fribourg, Ch. du Musée 10, Fribourg 1700, Switzerland
| | - Wilhelm Gruissem
- Department of Biology and Zurich-Basel Plant Science Center, ETH Zurich, Zurich CH-8092, Switzerland
| | - Daniel Hofius
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-75007, Sweden
| | - Lars Hennig
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-75007, Sweden
| |
Collapse
|
23
|
Abstract
To achieve optimal functionality, plant organs like leaves and petals have to grow to a certain size. Beginning with a limited number of undifferentiated cells, the final size of an organ is attained by a complex interplay of cell proliferation and subsequent cell expansion. Regulatory mechanisms that integrate intrinsic growth signals and environmental cues are required to enable optimal leaf and flower development. This review focuses on plant-specific principles of growth reaching from the cellular to the organ level. The currently known genetic pathways underlying these principles are summarized and network connections are highlighted. Putative non-cell autonomously acting mechanisms that might coordinate plant-cell growth are discussed.
Collapse
Affiliation(s)
- Hjördis Czesnick
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam 14476, Germany
| | - Michael Lenhard
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam 14476, Germany
| |
Collapse
|
24
|
Donà M, Mittelsten Scheid O. DNA Damage Repair in the Context of Plant Chromatin. PLANT PHYSIOLOGY 2015; 168:1206-18. [PMID: 26089404 PMCID: PMC4528755 DOI: 10.1104/pp.15.00538] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 06/17/2015] [Indexed: 05/03/2023]
Abstract
The integrity of DNA molecules is constantly challenged. All organisms have developed mechanisms to detect and repair multiple types of DNA lesions. The basic principles of DNA damage repair (DDR) in prokaryotes and unicellular and multicellular eukaryotes are similar, but the association of DNA with nucleosomes in eukaryotic chromatin requires mechanisms that allow access of repair enzymes to the lesions. This is achieved by chromatin-remodeling factors, and their necessity for efficient DDR has recently been demonstrated for several organisms and repair pathways. Plants share many features of chromatin organization and DNA repair with fungi and animals, but they differ in other, important details, which are both interesting and relevant for our understanding of genome stability and genetic diversity. In this Update, we compare the knowledge of the role of chromatin and chromatin-modifying factors during DDR in plants with equivalent systems in yeast and humans. We emphasize plant-specific elements and discuss possible implications.
Collapse
Affiliation(s)
- Mattia Donà
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter, 1030 Vienna, Austria
| | - Ortrun Mittelsten Scheid
- Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter, 1030 Vienna, Austria
| |
Collapse
|
25
|
Randall RS, Sornay E, Dewitte W, Murray JAH. AINTEGUMENTA and the D-type cyclin CYCD3;1 independently contribute to petal size control in Arabidopsis: evidence for organ size compensation being an emergent rather than a determined property. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:3991-4000. [PMID: 25948704 PMCID: PMC4473993 DOI: 10.1093/jxb/erv200] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Plant lateral aerial organ (LAO) growth is determined by the number and size of cells comprising the organ. Genetic alteration of one parameter is often accompanied by changes in the other, such that the overall effect on final LAO size is minimized, suggested to be caused by an active organ level 'compensation mechanism'. For example, the aintegumenta (ant) mutant exhibits reduced cell number but increased cell size in LAOs. The ANT transcription factor regulates the duration of the cell division phase of LAO growth, and its ectopic expression is correlated with increased levels of the cell cycle regulator CYCD3;1. This has previously led to the suggestion that ANT regulates CYCD3;1. It is shown here that while ANT is required for normal cell proliferation in petals, CYCD3;1 is not, suggesting that ANT does not regulate CYCD3;1 during petal growth. Moreover CYCD3;1 expression was similar in wild-type and ant-9 flowers. In contrast to the compensatory changes between cell size and number in ant mutants, cycd3;1 mutants show increased petal cell size unaccompanied by changes in cell number, leading to larger organs. However, loss of CYCD3;1 in the ant-9 mutant background leads to a phenotype consistent with compensation mechanisms. These apparently arbitrary examples of compensation are reconciled through a model of LAO growth in which distinct phases of division and cell expansion occupy differing lengths of a defined overall growth window. This leads to the proposal that many observations of 'compensation mechanisms' might alternatively be more simply explained as emergent properties of LAO development.
Collapse
Affiliation(s)
- Ricardo S Randall
- Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - Emily Sornay
- Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - Walter Dewitte
- Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - James A H Murray
- Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| |
Collapse
|
26
|
Hisanaga T, Kawade K, Tsukaya H. Compensation: a key to clarifying the organ-level regulation of lateral organ size in plants. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:1055-63. [PMID: 25635111 DOI: 10.1093/jxb/erv028] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Leaves are ideal model systems to study the organ size regulation of multicellular plants. Leaf cell number and cell size are determinant factors of leaf size which is controlled through cell proliferation and post-mitotic cell expansion, respectively. To achieve a proper leaf size, cell proliferation and post-mitotic cell expansion should be co-ordinated during leaf morphogenesis. Compensation, which is enhanced post-mitotic cell expansion associated with a decrease in cell number during lateral organ development, is suggestive of such co-ordination. Genetic and kinematic studies revealed at least three classes of modes of compensation, indicating that compensation is a heterogeneous phenomenon. Recent studies have increased our understanding about the molecular basis of compensation by identifying the causal genes of each compensation-exhibiting mutant. Furthermore, analyses using chimeric leaves revealed that a type of compensated cell expansion requires cell-to-cell communication. Information from recent advances in molecular and genetic studies on compensation has been integrated here and its role in organ size regulation is discussed.
Collapse
Affiliation(s)
- Tetsuya Hisanaga
- Graduate School of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Kensuke Kawade
- Department of Biological Sciences, Faculty of Science, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan
| | - Hirokazu Tsukaya
- Graduate School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| |
Collapse
|
27
|
Herridge RP, Day RC, Macknight RC. The role of the MCM2-7 helicase complex during Arabidopsis seed development. PLANT MOLECULAR BIOLOGY 2014; 86:69-84. [PMID: 24947836 DOI: 10.1007/s11103-014-0213-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 06/08/2014] [Indexed: 05/27/2023]
Abstract
The MINICHROMOSOME MAINTENANCE 2-7 (MCM2-7) complex, a ring-shaped heterohexamer, unwinds the DNA double helix ahead of the other replication machinery. Although there is evidence that individual components might have other roles, the essential nature of the MCM2-7 complex in DNA replication has made it difficult to uncover these. Here, we present a detailed analysis of Arabidopsis thaliana mcm2-7 mutants and reveal phenotypic differences. The MCM2-7 genes are coordinately expressed during development, although MCM7 is expressed at a higher level in the egg cell. Consistent with a role in the egg cell, heterozygous mcm7 mutants resulted in frequent ovule abortion, a phenotype that does not occur in other mcm mutants. All mutants showed a maternal effect, whereby seeds inheriting a maternal mutant allele occasionally aborted later in seed development with defects in embryo patterning, endosperm nuclear size, and cellularization, a phenotype that is variable between subunit mutants. We provide evidence that this maternal effect is due to the necessity of a maternal store of MCM protein in the central cell that is sufficient for maintaining seed viability and size in the absence of de novo MCM transcription. Reducing MCM levels using endosperm-specific RNAi constructs resulted in the up-regulation of DNA repair transcripts, consistent with the current hypothesis that excess MCM2-7 complexes are loaded during G1 phase, and are required during S phase to overcome replicative stress or DNA damage. Overall, this study demonstrates the importance of the MCM2-7 subunits during seed development and suggests that there are functional differences between the subunits.
Collapse
Affiliation(s)
- Rowan P Herridge
- Department of Biochemistry, University of Otago, Dunedin, 9054, New Zealand
| | | | | |
Collapse
|
28
|
Sablowski R, Carnier Dornelas M. Interplay between cell growth and cell cycle in plants. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:2703-14. [PMID: 24218325 DOI: 10.1093/jxb/ert354] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The growth of organs and whole plants depends on both cell growth and cell-cycle progression, but the interaction between both processes is poorly understood. In plants, the balance between growth and cell-cycle progression requires coordinated regulation of four different processes: macromolecular synthesis (cytoplasmic growth), turgor-driven cell-wall extension, mitotic cycle, and endocycle. Potential feedbacks between these processes include a cell-size checkpoint operating before DNA synthesis and a link between DNA contents and maximum cell size. In addition, key intercellular signals and growth regulatory genes appear to target at the same time cell-cycle and cell-growth functions. For example, auxin, gibberellin, and brassinosteroid all have parallel links to cell-cycle progression (through S-phase Cyclin D-CDK and the anaphase-promoting complex) and cell-wall functions (through cell-wall extensibility or microtubule dynamics). Another intercellular signal mediated by microtubule dynamics is the mechanical stress caused by growth of interconnected cells. Superimposed on developmental controls, sugar signalling through the TOR pathway has recently emerged as a central control point linking cytoplasmic growth, cell-cycle and cell-wall functions. Recent progress in quantitative imaging and computational modelling will facilitate analysis of the multiple interconnections between plant cell growth and cell cycle and ultimately will be required for the predictive manipulation of plant growth.
Collapse
Affiliation(s)
- Robert Sablowski
- Cell and Developmental Biology Department, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - Marcelo Carnier Dornelas
- Instituto de Biologia, Departamento de Biologia Vegetal, Universidade Estadual de Campinas, Campinas, SP, CEP 13083-862, Brazil
| |
Collapse
|
29
|
Hepworth J, Lenhard M. Regulation of plant lateral-organ growth by modulating cell number and size. CURRENT OPINION IN PLANT BIOLOGY 2014; 17:36-42. [PMID: 24507492 DOI: 10.1016/j.pbi.2013.11.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 11/04/2013] [Accepted: 11/06/2013] [Indexed: 05/23/2023]
Abstract
Leaves and floral organs grow to distinct, species-specific sizes and shapes. Research over the last few years has increased our understanding of how genetic pathways modulate cell proliferation and cell expansion to determine these sizes and shapes. In particular, the timing of proliferation arrest is an important point of control for organ size, and work on the regulators involved is showing how this control is achieved mechanistically and integrates environmental information. We are also beginning to understand how growth differs in different organs to produce their characteristic shapes, and how growth is integrated between different tissues that make up plant organs. Lastly, components of the general machinery in eukaryotic cells have been identified as having important roles in growth control.
Collapse
Affiliation(s)
- Jo Hepworth
- Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, House 26, 14476 Potsdam, Germany
| | - Michael Lenhard
- Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, House 26, 14476 Potsdam, Germany.
| |
Collapse
|
30
|
Roy S. Maintenance of genome stability in plants: repairing DNA double strand breaks and chromatin structure stability. FRONTIERS IN PLANT SCIENCE 2014; 5:487. [PMID: 25295048 PMCID: PMC4172009 DOI: 10.3389/fpls.2014.00487] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 09/03/2014] [Indexed: 05/19/2023]
Abstract
Plant cells are subject to high levels of DNA damage resulting from plant's obligatory dependence on sunlight and the associated exposure to environmental stresses like solar UV radiation, high soil salinity, drought, chilling injury, and other air and soil pollutants including heavy metals and metabolic by-products from endogenous processes. The irreversible DNA damages, generated by the environmental and genotoxic stresses affect plant growth and development, reproduction, and crop productivity. Thus, for maintaining genome stability, plants have developed an extensive array of mechanisms for the detection and repair of DNA damages. This review will focus recent advances in our understanding of mechanisms regulating plant genome stability in the context of repairing of double stand breaks and chromatin structure maintenance.
Collapse
Affiliation(s)
- Sujit Roy
- *Correspondence: Sujit Roy, Protein Chemistry Laboratory, Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, West Bengal, India e-mail:
| |
Collapse
|
31
|
Does ploidy level directly control cell size? Counterevidence from Arabidopsis genetics. PLoS One 2013; 8:e83729. [PMID: 24349549 PMCID: PMC3861520 DOI: 10.1371/journal.pone.0083729] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 11/14/2013] [Indexed: 12/19/2022] Open
Abstract
Ploidy level affects cell size in many organisms, and ploidy-dependent cell enlargement has been used to breed many useful organisms. However, how polyploidy affects cell size remains unknown. Previous studies have explored changes in transcriptome data caused by polyploidy, but have not been successful. The most naïve theory explaining ploidy-dependent cell enlargement is that increases in gene copy number increase the amount of protein, which in turn increases the cell volume. This hypothesis can be evaluated by examining whether any strains, mutants, or transgenics show the same cell size before and after a tetraploidization event. I performed this experiment by tetraploidizing various mutants and transgenics of Arabidopsis thaliana, which show a wide range in cell size, and found that the ploidy-dependent increase in cell volume is genetically regulated. This result is not in agreement with the theory described above.
Collapse
|
32
|
Ferjani A, Ishikawa K, Asaoka M, Ishida M, Horiguchi G, Maeshima M, Tsukaya H. Enhanced cell expansion in a KRP2 overexpressor is mediated by increased V-ATPase activity. PLANT & CELL PHYSIOLOGY 2013; 54:1989-98. [PMID: 24068796 DOI: 10.1093/pcp/pct138] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Decreased cell numbers during leaf development often trigger increased cell size, a phenomenon called compensation. In compensation-exhibiting mutants, the unusually high cell expansion activity occurs through two different mechanisms during the post-mitotic stage of leaf development, except in the KIP-RELATED PROTEIN 2-overexpressing line (KRP2 o/e), whose cell sizes are 2-fold greater during proliferative growth. However, the molecular basis of compensated cell expansion (CCE) has not been characterized. The det3-1 mutant has a mutation in the C-subunit of the vacuolar-type H(+)-ATPase (V-ATPase) complex that causes a 50% decrease in its activity and cell size. To determine the contribution of V-ATPase activity to CCE, the cellular phenotypes of double mutants between det3-1 and compensation-exhibiting fugu5-1, an3-4, fas1-5 and KRP2 o/e were analyzed in detail. Interestingly, while decreased V-ATPase activity caused by det3-1 did not suppress CCE in fugu5-1, fas1-5 and an3-4, CCE in KRP2 o/e was totally suppressed. Furthermore, measurements revealed that the activity and quantity of the A-subunit of the V-ATPase complex were significantly increased in the shoots of KRP2 o/e plants. Importantly, the unusually increased size of actively dividing KRP2 o/e cells was restored to normal in the det3-1 background. Taken together, our data strongly suggest that CCE in KRP2 o/e, but not in other compensation-exhibiting mutants, occurs exclusively through the increase of V-ATPase activity.
Collapse
Affiliation(s)
- Ali Ferjani
- Department of Biology, Tokyo Gakugei University, Koganei-shi, 184-8501 Japan
| | | | | | | | | | | | | |
Collapse
|
33
|
Ferjani A, Ishikawa K, Asaoka M, Ishida M, Horiguchi G, Maeshima M, Tsukaya H. Class III compensation, represented by KRP2 overexpression, depends on V-ATPase activity in proliferative cells. PLANT SIGNALING & BEHAVIOR 2013; 8:e27204. [PMID: 24305734 PMCID: PMC4091196 DOI: 10.4161/psb.27204] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Compensation refers to an increase in cell size when the cell number is significantly decreased due to the mutation or gain of function of a gene that negatively affects the cell cycle. Given the importance of coordinated growth during organogenesis in both animal and plant systems, compensation is important to understand the mechanism of size regulation. In leaves, cell division precedes cell differentiation (which involves cell expansion); therefore, a decrease in cell number triggers enhanced cell expansion (compensated cell expansion; hereafter, CCE). Functional analyses of genes for which a loss or gain of function triggers compensation have increased our understanding of the molecular mechanisms underlying the decrease in cell number. Nevertheless, the mechanisms that induce enhanced cell expansion (the link between cell cycling and expansion), as well as the cellular machinery mediating CCE, have not been characterized. We recently characterized an important pathway involved in cell enlargement in KRP2-overexpressing plants. Here, we discuss the potential axial role of plant KRPs in triggering enlargement in cells with meristematic features.
Collapse
Affiliation(s)
- Ali Ferjani
- Department of Biology; Tokyo Gakugei University; Koganei-shi, Japan
- Correspondence to: Ali Ferjani,
| | - Kazuki Ishikawa
- Department of Biology; Tokyo Gakugei University; Koganei-shi, Japan
| | - Mariko Asaoka
- Laboratory of Cell Dynamics; Graduate School of Bioagricultural Sciences; Nagoya University; Nagoya, Japan
| | - Masanori Ishida
- Department of Biology; Tokyo Gakugei University; Koganei-shi, Japan
| | - Gorou Horiguchi
- Department of Life Science; College of Science; Rikkyo University; Nishi-Ikebukuro, Japan
- Research Center for Life Science; College of Science; Rikkyo University; Nishi-Ikebukuro, Japan
| | - Masayoshi Maeshima
- Laboratory of Cell Dynamics; Graduate School of Bioagricultural Sciences; Nagoya University; Nagoya, Japan
| | - Hirokazu Tsukaya
- Department of Biological Sciences; Graduate School of Science; University of Tokyo; Bunkyo-ku, Japan
| |
Collapse
|