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Jiang Z, Zhao Y, Gao B, Wei X, Jiao P, Zhang H, Liu S, Guan S, Ma Y. ZmARF16 Regulates ZCN12 to Promote the Accumulation of Florigen and Accelerate Flowering. Int J Mol Sci 2024; 25:9607. [PMID: 39273554 PMCID: PMC11395262 DOI: 10.3390/ijms25179607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2024] [Revised: 08/31/2024] [Accepted: 09/03/2024] [Indexed: 09/15/2024] Open
Abstract
Auxin response factors(ARFs) are a class of transcription factors that regulate the expression of auxin response genes and play a crucial role in plant growth and development. Florigen plays a crucial role in the process of flowering. However, the process by which auxin regulates the accumulation of florigen remains largely unclear. This study found that the expression of ZmARF16 in maize increases during flowering, and the genetic transformation of ZmARF16 accelerates the flowering process in Arabidopsis and maize. Furthermore, ZmARF16 was found to be positively correlated with the transcription of the ZCN12 gene. Similarly, the FT-like gene ZCN12 in maize rescues the late flowering phenotype of the FT mutation in Arabidopsis. Moreover, ZCN12 actively participates in the accumulation of florigen and the flowering process. Further research revealed that ZmARF16 positively responds to the auxin signal, and that the interaction between ZmARF16 and the ZCN12 promoter, as well as the subsequent promotion of ZCN12 gene expression, leads to early flowering. This was confirmed through a yeast one-hybrid and dual-luciferase assay. Therefore, the study provides evidence that the ZmARF16-ZCN12 module plays a crucial role in regulating the flowering process of maize.
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Affiliation(s)
- Zhenzhong Jiang
- College of Life Sciences, Jilin Agricultural University, Changchun 130118, China
- Joint International Research Laboratory of Modern Agricultural Technology, Ministry of Education, Changchun 130118, China
| | - Yang Zhao
- Joint International Research Laboratory of Modern Agricultural Technology, Ministry of Education, Changchun 130118, China
- College of Agronomy, Jilin Agricultural University, Changchun 130118, China
| | - Bai Gao
- Joint International Research Laboratory of Modern Agricultural Technology, Ministry of Education, Changchun 130118, China
- College of Agronomy, Jilin Agricultural University, Changchun 130118, China
| | - Xiaotong Wei
- Joint International Research Laboratory of Modern Agricultural Technology, Ministry of Education, Changchun 130118, China
- College of Agronomy, Jilin Agricultural University, Changchun 130118, China
| | - Peng Jiao
- Joint International Research Laboratory of Modern Agricultural Technology, Ministry of Education, Changchun 130118, China
- College of Agronomy, Jilin Agricultural University, Changchun 130118, China
| | - Honglin Zhang
- Joint International Research Laboratory of Modern Agricultural Technology, Ministry of Education, Changchun 130118, China
- College of Agronomy, Jilin Agricultural University, Changchun 130118, China
| | - Siyan Liu
- Joint International Research Laboratory of Modern Agricultural Technology, Ministry of Education, Changchun 130118, China
- College of Agronomy, Jilin Agricultural University, Changchun 130118, China
| | - Shuyan Guan
- Joint International Research Laboratory of Modern Agricultural Technology, Ministry of Education, Changchun 130118, China
- College of Agronomy, Jilin Agricultural University, Changchun 130118, China
| | - Yiyong Ma
- Joint International Research Laboratory of Modern Agricultural Technology, Ministry of Education, Changchun 130118, China
- College of Agronomy, Jilin Agricultural University, Changchun 130118, China
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Phookaew P, Ma Y, Suzuki T, Stolze SC, Harzen A, Sano R, Nakagami H, Demura T, Ohtani M. Active protein ubiquitination regulates xylem vessel functionality. THE PLANT CELL 2024; 36:3298-3317. [PMID: 39092875 PMCID: PMC11371170 DOI: 10.1093/plcell/koae221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 06/18/2024] [Accepted: 07/22/2024] [Indexed: 08/04/2024]
Abstract
Xylem vessels function in the long-distance conduction of water in land plants. The NAC transcription factor VASCULAR-RELATED NAC-DOMAIN7 (VND7) is a master regulator of xylem vessel cell differentiation in Arabidopsis (Arabidopsis thaliana). We previously isolated suppressor of ectopic xylem vessel cell differentiation induced by VND7 (seiv) mutants. Here, we report that the responsible genes for seiv3, seiv4, seiv6, and seiv9 are protein ubiquitination-related genes encoding PLANT U-BOX46 (PUB46), an uncharacterized F-BOX protein (FBX), PUB36, and UBIQUITIN-SPECIFIC PROTEASE1 (UBP1), respectively. We also found decreased expression of genes downstream of VND7 and abnormal xylem transport activity in the seiv mutants. Upon VND7 induction, ubiquitination levels from 492 and 180 protein groups were upregulated and downregulated, respectively. VND7 induction resulted in the ubiquitination of proteins for cell wall biosynthesis and protein transport, whereas such active protein ubiquitination did not occur in the seiv mutants. We detected the ubiquitination of three lysine residues in VND7: K94, K105, and K260. Substituting K94 with arginine significantly decreased the transactivation activity of VND7, suggesting that the ubiquitination of K94 is crucial for regulating VND7 activity. Our findings highlight the crucial roles of target protein ubiquitination in regulating xylem vessel activity.
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Affiliation(s)
- Pawittra Phookaew
- Graduate School of Science and Technology, Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Ya Ma
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8562, Japan
| | - Takaomi Suzuki
- Graduate School of Science and Technology, Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Sara Christina Stolze
- Protein Mass Spectrometry, Max Planck Institute for Plant Breeding Research, Cologne 50829, Germany
| | - Anne Harzen
- Protein Mass Spectrometry, Max Planck Institute for Plant Breeding Research, Cologne 50829, Germany
| | - Ryosuke Sano
- Graduate School of Science and Technology, Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Hirofumi Nakagami
- Protein Mass Spectrometry, Max Planck Institute for Plant Breeding Research, Cologne 50829, Germany
| | - Taku Demura
- Graduate School of Science and Technology, Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
- Center for Sustainable Resource Science, RIKEN, Yokohama 230-0045, Japan
| | - Misato Ohtani
- Graduate School of Science and Technology, Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8562, Japan
- Center for Sustainable Resource Science, RIKEN, Yokohama 230-0045, Japan
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3
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Du Q, Yuan B, Thapa Chhetri G, Wang T, Qi L, Wang H. A transcriptional repressor HVA regulates vascular bundle formation through auxin transport in Arabidopsis stem. THE NEW PHYTOLOGIST 2024; 243:1681-1697. [PMID: 39014537 DOI: 10.1111/nph.19970] [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: 04/29/2024] [Accepted: 07/02/2024] [Indexed: 07/18/2024]
Abstract
Vascular bundles transport water and photosynthate to all organs, and increased bundle number contributes to crop lodging resistance. However, the regulation of vascular bundle formation is poorly understood in the Arabidopsis stem. We report a novel semi-dominant mutant with high vascular activity, hva-d, showing increased vascular bundle number and enhanced cambium proliferation in the stem. The activation of a C2H2 zinc finger transcription factor, AT5G27880/HVA, is responsible for the hva-d phenotype. Genetic, biochemical, and fluorescent microscopic analyses were used to dissect the functions of HVA. HVA functions as a repressor and interacts with TOPLESS via the conserved Ethylene-responsive element binding factor-associated Amphiphilic Repression motif. In contrast to the HVA activation line, knockout of HVA function with a CRISPR-Cas9 approach or expression of HVA fused with an activation domain VP16 (HVA-VP16) resulted in fewer vascular bundles. Further, HVA directly regulates the expression of the auxin transport efflux facilitator PIN1, as a result affecting auxin accumulation. Genetics analysis demonstrated that PIN1 is epistatic to HVA in controlling bundle number. This research identifies HVA as a positive regulator of vascular initiation through negatively modulating auxin transport and sheds new light on the mechanism of bundle formation in the stem.
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Affiliation(s)
- Qian Du
- Department of Plant Science and Landscape Architecture, University of Connecticut, 1376 Storrs Rd, Storrs, CT, 06269, USA
| | - Bingjian Yuan
- Department of Plant Science and Landscape Architecture, University of Connecticut, 1376 Storrs Rd, Storrs, CT, 06269, USA
| | - Gaurav Thapa Chhetri
- Department of Plant Science and Landscape Architecture, University of Connecticut, 1376 Storrs Rd, Storrs, CT, 06269, USA
| | - Tong Wang
- Department of Plant Science and Landscape Architecture, University of Connecticut, 1376 Storrs Rd, Storrs, CT, 06269, USA
| | - Liying Qi
- Department of Plant Science and Landscape Architecture, University of Connecticut, 1376 Storrs Rd, Storrs, CT, 06269, USA
| | - Huanzhong Wang
- Department of Plant Science and Landscape Architecture, University of Connecticut, 1376 Storrs Rd, Storrs, CT, 06269, USA
- Institute for System Genomics, University of Connecticut, Storrs, CT, 06269, USA
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Rabeh K, Oubohssaine M, Hnini M. TOR in plants: Multidimensional regulators of plant growth and signaling pathways. JOURNAL OF PLANT PHYSIOLOGY 2024; 294:154186. [PMID: 38330538 DOI: 10.1016/j.jplph.2024.154186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 01/20/2024] [Accepted: 01/22/2024] [Indexed: 02/10/2024]
Abstract
Target Of Rapamycin (TOR) represents a ubiquitous kinase complex that has emerged as a central regulator of cell growth and metabolism in nearly all eukaryotic organisms. TOR is an evolutionarily conserved protein kinase, functioning as a central signaling hub that integrates diverse internal and external cues to regulate a multitude of biological processes. These processes collectively exert significant influence on plant growth, development, nutrient assimilation, photosynthesis, fruit ripening, and interactions with microorganisms. Within the plant domain, the TOR complex comprises three integral components: TOR, RAPTOR, and LST8. This comprehensive review provides insights into various facets of the TOR protein, encompassing its origin, structure, function, and the regulatory and signaling pathways operative in photosynthetic organisms. Additionally, we explore future perspectives related to this pivotal protein kinase.
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Affiliation(s)
- Karim Rabeh
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco.
| | - Malika Oubohssaine
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco
| | - Mohamed Hnini
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco
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Kim SH, Lee SH, Park TK, Tian Y, Yu K, Lee BH, Bai MY, Cho SJ, Kim TW. Comparative analysis of BZR1/BES1 family transcription factors in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 117:747-765. [PMID: 37926922 DOI: 10.1111/tpj.16527] [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: 06/04/2023] [Revised: 09/26/2023] [Accepted: 10/23/2023] [Indexed: 11/07/2023]
Abstract
Brassinazole Resistant 1 (BZR1) and bri1 EMS Suppressor 1 (BES1) are key transcription factors that mediate brassinosteroid (BR)-responsive gene expression in Arabidopsis. The BZR1/BES1 family is composed of BZR1, BES1, and four BES1/BZR1 homologs (BEH1-BEH4). However, little is known about whether BEHs are regulated by BR signaling in the same way as BZR1 and BES1. We comparatively analyzed the functional characteristics of six BZR1/BES1 family members and their regulatory mechanisms in BR signaling using genetic and biochemical analyses. We also compared their subcellular localizations regulated by the phosphorylation status, interaction with GSK3-like kinases, and heterodimeric combination. We found that all BZR1/BES1 family members restored the phenotypic defects of bri1-5 by their overexpression. Unexpectedly, BEH2-overexpressing plants showed the most distinct phenotype with enhanced BR responses. RNA-Seq analysis indicated that overexpression of both BZR1 and BEH2 regulates BR-responsive gene expression, but BEH2 has a much greater proportion of BR-independent gene expression than BZR1. Unlike BZR1 and BES1, the BR-regulated subcellular translocation of the four BEHs was not tightly correlated with their phosphorylation status. Notably, BEH1 and BEH2 are predominantly localized in the nucleus, which induces the nuclear accumulation of other BZR1/BES1 family proteins through heterodimerization. Altogether, our comparative analyses suggest that BEH1 and BEH2 play an important role in the functional interaction between BZR1/BES1 family transcription factors.
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Affiliation(s)
- So-Hee Kim
- Department of Life Science, Hanyang University, Seoul, 04763, Republic of Korea
- Research Institute for Convergence of Basic Science, Hanyang University, Seoul, 04763, Republic of Korea
| | - Se-Hwa Lee
- Department of Life Science, Hanyang University, Seoul, 04763, Republic of Korea
- Research Institute for Convergence of Basic Science, Hanyang University, Seoul, 04763, Republic of Korea
| | - Tae-Ki Park
- Department of Life Science, Hanyang University, Seoul, 04763, Republic of Korea
- Hanyang Institute of Bioscience and Biotechnology, Hanyang University, Seoul, 04763, Republic of Korea
| | - Yanchen Tian
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, 266237, China
| | - Kyoungjae Yu
- Department of Life Science, Sogang University, Seoul, 04107, Republic of Korea
| | - Byeong-Ha Lee
- Department of Life Science, Sogang University, Seoul, 04107, Republic of Korea
| | - Ming-Yi Bai
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, 266237, China
| | - Sung-Jin Cho
- School of Biological Sciences, College of Natural Sciences, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Tae-Wuk Kim
- Department of Life Science, Hanyang University, Seoul, 04763, Republic of Korea
- Research Institute for Convergence of Basic Science, Hanyang University, Seoul, 04763, Republic of Korea
- Hanyang Institute of Bioscience and Biotechnology, Hanyang University, Seoul, 04763, Republic of Korea
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Zhang S, Cao L, Chang R, Zhang H, Yu J, Li C, Liu G, Yan J, Xu Z. Network Analysis of Metabolome and Transcriptome Revealed Regulation of Different Nitrogen Concentrations on Hybrid Poplar Cambium Development. Int J Mol Sci 2024; 25:1017. [PMID: 38256092 PMCID: PMC10816006 DOI: 10.3390/ijms25021017] [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: 12/19/2023] [Revised: 01/08/2024] [Accepted: 01/11/2024] [Indexed: 01/24/2024] Open
Abstract
Secondary development is a key biological characteristic of woody plants and the basis of wood formation. Exogenous nitrogen can affect the secondary growth of poplar, and some regulatory mechanisms have been found in the secondary xylem. However, the effect of nitrogen on cambium has not been reported. Herein, we investigated the effects of different nitrogen concentrations on cambium development using combined transcriptome and metabolome analysis. The results show that, compared with 1 mM NH4NO3 (M), the layers of hybrid poplar cambium cells decreased under the 0.15 mM NH4NO3 (L) and 0.3 mM NH4NO3 (LM) treatments. However, there was no difference in the layers of hybrid poplar cambium cells under the 3 mM NH4NO3 (HM) and 5 mM NH4NO3 (H) treatments. Totals of 2365, 824, 649 and 398 DEGs were identified in the M versus (vs.) L, M vs. LM, M vs. HM and M vs. H groups, respectively. Expression profile analysis of the DEGs showed that exogenous nitrogen affected the gene expression involved in plant hormone signal transduction, phenylpropanoid biosynthesis, the starch and sucrose metabolism pathway and the ubiquitin-mediated proteolysis pathway. In M vs. L, M vs. LM, M vs. HM and M vs. H, differential metabolites were enriched in flavonoids, lignans, coumarins and saccharides. The combined analysis of the transcriptome and metabolome showed that some genes and metabolites in plant hormone signal transduction, phenylpropanoid biosynthesis and starch and sucrose metabolism pathways may be involved in nitrogen regulation in cambium development, whose functions need to be verified. In this study, from the point of view that nitrogen influences cambium development to regulate wood formation, the network analysis of the transcriptome and metabolomics of cambium under different nitrogen supply levels was studied for the first time, revealing the potential regulatory and metabolic mechanisms involved in this process and providing new insights into the effects of nitrogen on wood development.
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Affiliation(s)
- Shuang Zhang
- College of Life Science, Northeast Forestry University, Harbin 150040, China; (S.Z.); (R.C.)
| | - Lina Cao
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (L.C.); (H.Z.); (J.Y.); (C.L.); (G.L.)
| | - Ruhui Chang
- College of Life Science, Northeast Forestry University, Harbin 150040, China; (S.Z.); (R.C.)
| | - Heng Zhang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (L.C.); (H.Z.); (J.Y.); (C.L.); (G.L.)
| | - Jiajie Yu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (L.C.); (H.Z.); (J.Y.); (C.L.); (G.L.)
| | - Chunming Li
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (L.C.); (H.Z.); (J.Y.); (C.L.); (G.L.)
| | - Guanjun Liu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (L.C.); (H.Z.); (J.Y.); (C.L.); (G.L.)
| | - Junxin Yan
- College of Landscape Architecture, Northeast Forestry University, Harbin 150040, China
| | - Zhiru Xu
- College of Life Science, Northeast Forestry University, Harbin 150040, China; (S.Z.); (R.C.)
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China; (L.C.); (H.Z.); (J.Y.); (C.L.); (G.L.)
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Lindsay P, Swentowsky KW, Jackson D. Cultivating potential: Harnessing plant stem cells for agricultural crop improvement. MOLECULAR PLANT 2024; 17:50-74. [PMID: 38130059 DOI: 10.1016/j.molp.2023.12.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 12/14/2023] [Accepted: 12/18/2023] [Indexed: 12/23/2023]
Abstract
Meristems are stem cell-containing structures that produce all plant organs and are therefore important targets for crop improvement. Developmental regulators control the balance and rate of cell divisions within the meristem. Altering these regulators impacts meristem architecture and, as a consequence, plant form. In this review, we discuss genes involved in regulating the shoot apical meristem, inflorescence meristem, axillary meristem, root apical meristem, and vascular cambium in plants. We highlight several examples showing how crop breeders have manipulated developmental regulators to modify meristem growth and alter crop traits such as inflorescence size and branching patterns. Plant transformation techniques are another innovation related to plant meristem research because they make crop genome engineering possible. We discuss recent advances on plant transformation made possible by studying genes controlling meristem development. Finally, we conclude with discussions about how meristem research can contribute to crop improvement in the coming decades.
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Affiliation(s)
- Penelope Lindsay
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | | | - David Jackson
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
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8
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Ai W, Liu H, Wang Y, Wang Y, Wei J, Zhang X, Lu X. Identification of Functional Brassinosteroid Receptor Genes in Oaks and Functional Analysis of QmBRI1. Int J Mol Sci 2023; 24:16405. [PMID: 38003597 PMCID: PMC10671120 DOI: 10.3390/ijms242216405] [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: 10/11/2023] [Revised: 11/10/2023] [Accepted: 11/13/2023] [Indexed: 11/26/2023] Open
Abstract
Brassinosteroids (BRs) play important regulatory roles in plant growth and development, with functional BR receptors being crucial for BR recognition or signaling. Although functional BR receptors have been extensively studied in herbaceous plants, they remain largely under-studied in forest tree species. In this study, nine BR receptors were identified in three representative oak species, of which BRI1s and BRL1s were functional BR receptors. Dispersed duplications were a driving force for oak BR receptor expansion, among which the Brassinosteroid-Insensitive-1 (BRI1)-type genes diverged evolutionarily from most rosids. In oak BRI1s, we identified that methionine in the conserved Asn-Gly-Ser-Met (NGSM) motif was replaced by isoleucine and that the amino acid mutation occurred after the divergence of Quercus and Fagus. Compared with QmBRL1, QmBRI1 was relatively highly expressed during BR-induced xylem differentiation and in young leaves, shoots, and the phloem and xylem of young stems of Quercus mongolica. Based on Arabidopsis complementation experiments, we proved the important role of QmBRI1 in oak growth and development, especially in vascular patterning and xylem differentiation. These findings serve as an important supplement to the findings of the structural, functional and evolutionary studies on functional BR receptors in woody plants and provide the first example of natural mutation occurring in the conserved BR-binding region (NGSM motif) of angiosperm BRI1s.
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Affiliation(s)
- Wanfeng Ai
- College of Forestry, Shenyang Agricultural University, Shenyang 110866, China; (W.A.)
- Key Laboratory for Silviculture of Liaoning Province, Shenyang 110866, China
| | - Hanzhang Liu
- College of Forestry, Shenyang Agricultural University, Shenyang 110866, China; (W.A.)
- Key Laboratory for Silviculture of Liaoning Province, Shenyang 110866, China
| | - Yutao Wang
- College of Forestry, Shenyang Agricultural University, Shenyang 110866, China; (W.A.)
- Key Laboratory for Silviculture of Liaoning Province, Shenyang 110866, China
| | - Yu Wang
- College of Forestry, Shenyang Agricultural University, Shenyang 110866, China; (W.A.)
- Key Laboratory for Silviculture of Liaoning Province, Shenyang 110866, China
| | - Jun Wei
- College of Forestry, Shenyang Agricultural University, Shenyang 110866, China; (W.A.)
- Key Laboratory for Silviculture of Liaoning Province, Shenyang 110866, China
| | - Xiaolin Zhang
- College of Forestry, Shenyang Agricultural University, Shenyang 110866, China; (W.A.)
- Key Laboratory for Silviculture of Liaoning Province, Shenyang 110866, China
| | - Xiujun Lu
- College of Forestry, Shenyang Agricultural University, Shenyang 110866, China; (W.A.)
- Key Laboratory for Silviculture of Liaoning Province, Shenyang 110866, China
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Guo X, Li Y, Li N, Li G, Sun Y, Zhang S. BvCPD promotes parenchyma cell and vascular bundle development in sugar beet ( Beta vulgaris L.) taproot. FRONTIERS IN PLANT SCIENCE 2023; 14:1271329. [PMID: 37771491 PMCID: PMC10523326 DOI: 10.3389/fpls.2023.1271329] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 08/28/2023] [Indexed: 09/30/2023]
Abstract
Constitutive photomorpogenic dwarf (CPD) is a pivotal enzyme gene for brassinolide (BR) synthesis and plays an important role in plant growth, including increasing plant biomass and plant height, elongating cells, and promoting xylem differentiation. However, little is known about the function of the CPD gene in sugar beet. In the current study, we isolated CPD from Beta vulgaris L. (BvCPD), which encodes protein localized in the nucleus, cell membrane, and cell wall. BvCPD was strongly expressed in parenchyma cells and vascular bundles. The transgenic sugar beet overexpressing BvCPD exhibited larger diameter than that of the wild type (WT), which mainly owing to the increased number and size of parenchyma cells, the enlarged lumen and area of vessel in the xylem. Additionally, overexpression of BvCPD increased the synthesis of endogenous BR, causing changes in the content of endogenous auxin (IAA) and gibberellin (GA) and accumulation of cellulose and lignin in cambium 1-4 rings of the taproot. These results suggest that BvCPD can promote the biosynthesis of endogenous BR, improve cell wall components, promote the development of parenchyma cells and vascular bundle, thereby playing an important role in promoting the growth and development of sugar beet taproot.
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Affiliation(s)
| | | | | | | | - Yaqing Sun
- Sugar Beet Physiological Research Institute, Inner Mongolia Agricultural University, Hohhot, China
| | - Shaoying Zhang
- Sugar Beet Physiological Research Institute, Inner Mongolia Agricultural University, Hohhot, China
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10
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Wei H, Song Z, Xie Y, Cheng H, Yan H, Sun F, Liu H, Shen J, Li L, He X, Wang H, Luo K. High temperature inhibits vascular development via the PIF4-miR166-HB15 module in Arabidopsis. Curr Biol 2023; 33:3203-3214.e4. [PMID: 37442138 DOI: 10.1016/j.cub.2023.06.049] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/16/2023] [Accepted: 06/19/2023] [Indexed: 07/15/2023]
Abstract
The plant vascular system is an elaborate network of conducting and supporting tissues that extends throughout the plant body, and its structure and function must be orchestrated with different environmental conditions. Under high temperature, plants display thin and lodging stems that may lead to decreased yield and quality of crops. However, the molecular mechanism underlying high-temperature-mediated regulation of vascular development is not known. Here, we show that Arabidopsis plants overexpressing the basic-helix-loop-helix (bHLH) transcription factor PHYTOCHROME INTERACTING FACTOR 4 (PIF4), a central regulator of high-temperature signaling, display fewer vascular bundles (VBs) and decreased secondary cell wall (SCW) thickening, mimicking the lodging inflorescence stems of high-temperature-grown wild-type plants. Rising temperature and elevated PIF4 expression reduced the expression of MIR166 and, concomitantly, elevated the expression of the downstream class III homeodomain leucine-zipper (HD-ZIP III) family gene HB15. Consistently, knockdown of miR166 and overexpression of HB15 led to inhibition of vascular development and SCW formation, whereas the hb15 mutant displayed the opposite phenotype in response to high temperature. Moreover, in vitro and in vivo assays verified that PIF4 binds to the promoters of several MIR166 genes and represses their expression. Our study establishes a direct functional link between PIF4 and the miR166-HB15 module in modulating vascular development and SCW thickening and consequently stem-lodging susceptibility at elevated temperatures.
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Affiliation(s)
- Hongbin Wei
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Zhi Song
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Yurong Xie
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Hongli Cheng
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Huiting Yan
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Fan Sun
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Huajie Liu
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Junlong Shen
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Laigeng Li
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Xinhua He
- Centre of Excellence for Soil Biology, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Haiyang Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China.
| | - Keming Luo
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, Chongqing 400715, China; Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China.
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11
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Hardtke CS. Phloem development. THE NEW PHYTOLOGIST 2023. [PMID: 37243530 DOI: 10.1111/nph.19003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Accepted: 04/13/2023] [Indexed: 05/29/2023]
Abstract
The evolution of the plant vascular system is a key process in Earth history because it enabled plants to conquer land and transform the terrestrial surface. Among the vascular tissues, the phloem is particularly intriguing because of its complex functionality. In angiosperms, its principal components are the sieve elements, which transport phloem sap, and their neighboring companion cells. Together, they form a functional unit that sustains sap loading, transport, and unloading. The developmental trajectory of sieve elements is unique among plant cell types because it entails selective organelle degradation including enucleation. Meticulous analyses of primary, so-called protophloem in the Arabidopsis thaliana root meristem have revealed key steps in protophloem sieve element formation at single-cell resolution. A transcription factor cascade connects specification with differentiation and also orchestrates phloem pole patterning via noncell-autonomous action of sieve element-derived effectors. Reminiscent of vascular tissue patterning in secondary growth, these involve receptor kinase pathways, whose antagonists guide the progression of sieve element differentiation. Receptor kinase pathways may also safeguard phloem formation by maintaining the developmental plasticity of neighboring cell files. Our current understanding of protophloem development in the A. thaliana root has reached sufficient detail to instruct molecular-level investigation of phloem formation in other organs.
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Affiliation(s)
- Christian S Hardtke
- Department of Plant Molecular Biology, University of Lausanne, CH-1015, Lausanne, Switzerland
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12
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Costigliolo Rojas C, Bianchimano L, Oh J, Romero Montepaone S, Tarkowská D, Minguet EG, Schön J, García Hourquet M, Flugel T, Blázquez MA, Choi G, Strnad M, Mora-García S, Alabadi D, Zurbriggen MD, Casal JJ. Organ-specific COP1 control of BES1 stability adjusts plant growth patterns under shade or warmth. Dev Cell 2022; 57:2009-2025.e6. [PMID: 35901789 DOI: 10.1016/j.devcel.2022.07.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 02/16/2022] [Accepted: 07/05/2022] [Indexed: 11/18/2022]
Abstract
Under adverse conditions such as shade or elevated temperatures, cotyledon expansion is reduced and hypocotyl growth is promoted to optimize plant architecture. The mechanisms underlying the repression of cotyledon cell expansion remain unknown. Here, we report that the nuclear abundance of the BES1 transcription factor decreased in the cotyledons and increased in the hypocotyl in Arabidopsis thaliana under shade or warmth. Brassinosteroid levels did not follow the same trend. PIF4 and COP1 increased their nuclear abundance in both organs under shade or warmth. PIF4 directly bound the BES1 promoter to enhance its activity but indirectly reduced BES1 expression. COP1 physically interacted with the BES1 protein, promoting its proteasome degradation in the cotyledons. COP1 had the opposite effect in the hypocotyl, demonstrating organ-specific regulatory networks. Our work indicates that shade or warmth reduces BES1 activity by transcriptional and post-translational regulation to inhibit cotyledon cell expansion.
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Affiliation(s)
- Cecilia Costigliolo Rojas
- Fundaciόn Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, 1405 Buenos Aires, Argentina
| | - Luciana Bianchimano
- Fundaciόn Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, 1405 Buenos Aires, Argentina
| | - Jeonghwa Oh
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
| | - Sofía Romero Montepaone
- Institute of Synthetic Biology and Cluster of Excellence in Plant Sciences, University of Düsseldorf, 40225 Düsseldorf, Germany
| | - Dana Tarkowská
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc, Czech Republic
| | - Eugenio G Minguet
- Instituto de Biologίa Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas, Universidad Politécnica de Valencia, 46022 Valencia, Spain
| | - Jonas Schön
- Institute of Synthetic Biology and Cluster of Excellence in Plant Sciences, University of Düsseldorf, 40225 Düsseldorf, Germany
| | - Mariano García Hourquet
- Fundaciόn Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, 1405 Buenos Aires, Argentina
| | - Timo Flugel
- Fundaciόn Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, 1405 Buenos Aires, Argentina
| | - Miguel A Blázquez
- Instituto de Biologίa Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas, Universidad Politécnica de Valencia, 46022 Valencia, Spain
| | - Giltsu Choi
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental Botany, Czech Academy of Sciences, Olomouc, Czech Republic
| | - Santiago Mora-García
- Fundaciόn Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, 1405 Buenos Aires, Argentina
| | - David Alabadi
- Instituto de Biologίa Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas, Universidad Politécnica de Valencia, 46022 Valencia, Spain
| | - Matias D Zurbriggen
- Institute of Synthetic Biology and Cluster of Excellence in Plant Sciences, University of Düsseldorf, 40225 Düsseldorf, Germany
| | - Jorge J Casal
- Fundaciόn Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, 1405 Buenos Aires, Argentina; Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura, Facultad de Agronomía, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, 1417 Buenos Aires, Argentina.
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13
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Current Understanding of the Genetics and Molecular Mechanisms Regulating Wood Formation in Plants. Genes (Basel) 2022; 13:genes13071181. [PMID: 35885964 PMCID: PMC9319765 DOI: 10.3390/genes13071181] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 06/24/2022] [Accepted: 06/29/2022] [Indexed: 11/17/2022] Open
Abstract
Unlike herbaceous plants, woody plants undergo volumetric growth (a.k.a. secondary growth) through wood formation, during which the secondary xylem (i.e., wood) differentiates from the vascular cambium. Wood is the most abundant biomass on Earth and, by absorbing atmospheric carbon dioxide, functions as one of the largest carbon sinks. As a sustainable and eco-friendly energy source, lignocellulosic biomass can help address environmental pollution and the global climate crisis. Studies of Arabidopsis and poplar as model plants using various emerging research tools show that the formation and proliferation of the vascular cambium and the differentiation of xylem cells require the modulation of multiple signals, including plant hormones, transcription factors, and signaling peptides. In this review, we summarize the latest knowledge on the molecular mechanism of wood formation, one of the most important biological processes on Earth.
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14
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Cieslak M, Owens A, Prusinkiewicz P. Computational Models of Auxin-Driven Patterning in Shoots. Cold Spring Harb Perspect Biol 2022; 14:a040097. [PMID: 34001531 PMCID: PMC8886983 DOI: 10.1101/cshperspect.a040097] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Auxin regulates many aspects of plant development and behavior, including the initiation of new outgrowth, patterning of vascular systems, control of branching, and responses to the environment. Computational models have complemented experimental studies of these processes. We review these models from two perspectives. First, we consider cellular and tissue-level models of interaction between auxin and its transporters in shoots. These models form a coherent body of results exploring different hypotheses pertinent to the patterning of new outgrowth and vascular strands. Second, we consider models operating at the level of plant organs and entire plants. We highlight techniques used to reduce the complexity of these models, which provide a path to capturing the essence of studied phenomena while running simulations efficiently.
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Affiliation(s)
- Mikolaj Cieslak
- Department of Computer Science, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Andrew Owens
- Department of Computer Science, University of Calgary, Calgary, Alberta T2N 1N4, Canada
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15
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Wang C, Liu N, Geng Z, Ji M, Wang S, Zhuang Y, Wang D, He G, Zhao S, Zhou G, Chai G. Integrated transcriptome and proteome analysis reveals brassinosteroid-mediated regulation of cambium initiation and patterning in woody stem. HORTICULTURE RESEARCH 2022; 9:6497794. [PMID: 35031795 PMCID: PMC8788366 DOI: 10.1093/hr/uhab048] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 06/30/2021] [Accepted: 08/20/2021] [Indexed: 05/20/2023]
Abstract
Wood formation involves sequential developmental events requiring the coordination of multiple hormones. Brassinosteroids (BRs) play a key role in wood development, but little is known about the cellular and molecular processes that underlie wood formation in tree species. Here, we generated transgenic poplar lines with edited PdBRI1 genes, which are orthologs of Arabidopsis vascular-enriched BR receptors, and showed how inhibition of BR signaling influences wood development at the mRNA and/or proteome level. Six Populus PdBRI1 genes formed three gene pairs, each of which was highly expressed in basal stems. Simultaneous mutation of PdBRI1-1, -2, -3 and - 6, which are orthologs of the Arabidopsis vascular-enriched BR receptors BRI1, BRL1 and BRL3, resulted in severe growth defects. In particular, the stems of these mutant lines displayed a discontinuous cambial ring and patterning defects in derived secondary vascular tissues. Abnormal cambial formation within the cortical parenchyma was also observed in the stems of pdbri1-1;2;3;6. Transgenic poplar plants expressing edited versions of PdBRI1-1 or PdBRI1-1;2;6 exhibited phenotypic alterations in stem development at 4.5 months of growth, indicating that there is functional redundancy among these PdBRI1 genes. Integrated analysis of the transcriptome and proteome of pdbri1-1;2;3;6 stems revealed differential expression of a number of genes/proteins associated with wood development and hormones. Concordant (16%) and discordant (84%) regulation of mRNA and protein expression, including wood-associated mRNA/protein expression, was found in pdbri1-1;2;3;6 stems. This study found a dual role of BRs in procambial cell division and xylem differentiation and provides insights into the multiple layers of gene regulation that contribute to wood formation in Populus.
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Affiliation(s)
- Congpeng Wang
- College of Resources and Environment, Qingdao Agricultural University, Qingdao 266109, China
- Academy of Dongying Efficient Agricultural Technology and Industry on Saline and Alkaline Land in Collaboration with Qingdao Agricultural University, Dongying 257000, China
| | - Naixu Liu
- College of Resources and Environment, Qingdao Agricultural University, Qingdao 266109, China
| | - Zhao Geng
- College of Resources and Environment, Qingdao Agricultural University, Qingdao 266109, China
| | - Meijing Ji
- College of Resources and Environment, Qingdao Agricultural University, Qingdao 266109, China
| | - Shumin Wang
- Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Yamei Zhuang
- Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Dian Wang
- College of Agronomy, Qingdao Agricultural University, Qingdao 266109, China
| | - Guo He
- Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Shutang Zhao
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Gongke Zhou
- College of Resources and Environment, Qingdao Agricultural University, Qingdao 266109, China
- Academy of Dongying Efficient Agricultural Technology and Industry on Saline and Alkaline Land in Collaboration with Qingdao Agricultural University, Dongying 257000, China
- Corresponding authors. E-mail: ,
| | - Guohua Chai
- College of Resources and Environment, Qingdao Agricultural University, Qingdao 266109, China
- Academy of Dongying Efficient Agricultural Technology and Industry on Saline and Alkaline Land in Collaboration with Qingdao Agricultural University, Dongying 257000, China
- Corresponding authors. E-mail: ,
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16
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Albertos P, Dündar G, Schenk P, Carrera S, Cavelius P, Sieberer T, Poppenberger B. Transcription factor BES1 interacts with HSFA1 to promote heat stress resistance of plants. EMBO J 2022; 41:e108664. [PMID: 34981847 PMCID: PMC8804921 DOI: 10.15252/embj.2021108664] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 12/05/2021] [Accepted: 12/08/2021] [Indexed: 12/18/2022] Open
Abstract
Heat stress is a major environmental stress type that can limit plant growth and development. To survive sudden temperature increases, plants utilize the heat shock response, an ancient signaling pathway. Initial results had suggested a role for brassinosteroids (BRs) in this response. Brassinosteroids are growth-promoting steroid hormones whose activity is mediated by transcription factors of the BES1/BZR1 subfamily. Here, we provide evidence that BES1 can contribute to heat stress signaling. In response to heat, BES1 is activated even in the absence of BRs and directly binds to heat shock elements (HSEs), known binding sites of heat shock transcription factors (HSFs). HSFs of the HSFA1 type can interact with BES1 and facilitate its activity in HSE binding. These findings lead us to propose an extended model of the heat stress response in plants, in which the recruitment of BES1 is a means of heat stress signaling cross-talk with a central growth regulatory pathway.
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Affiliation(s)
- Pablo Albertos
- Biotechnology of Horticultural Crops, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Gönül Dündar
- Biotechnology of Horticultural Crops, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Philipp Schenk
- Biotechnology of Horticultural Crops, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Sergio Carrera
- Biotechnology of Horticultural Crops, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Philipp Cavelius
- Biotechnology of Horticultural Crops, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Tobias Sieberer
- Plant Growth Regulation, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Brigitte Poppenberger
- Biotechnology of Horticultural Crops, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
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17
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Mazzoni-Putman SM, Brumos J, Zhao C, Alonso JM, Stepanova AN. Auxin Interactions with Other Hormones in Plant Development. Cold Spring Harb Perspect Biol 2021; 13:a039990. [PMID: 33903155 PMCID: PMC8485746 DOI: 10.1101/cshperspect.a039990] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Auxin is a crucial growth regulator that governs plant development and responses to environmental perturbations. It functions at the heart of many developmental processes, from embryogenesis to organ senescence, and is key to plant interactions with the environment, including responses to biotic and abiotic stimuli. As remarkable as auxin is, it does not act alone, but rather solicits the help of, or is solicited by, other endogenous signals, including the plant hormones abscisic acid, brassinosteroids, cytokinins, ethylene, gibberellic acid, jasmonates, salicylic acid, and strigolactones. The interactions between auxin and other hormones occur at multiple levels: hormones regulate one another's synthesis, transport, and/or response; hormone-specific transcriptional regulators for different pathways physically interact and/or converge on common target genes; etc. However, our understanding of this crosstalk is still fragmentary, with only a few pieces of the gigantic puzzle firmly established. In this review, we provide a glimpse into the complexity of hormone interactions that involve auxin, underscoring how patchy our current understanding is.
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Affiliation(s)
- Serina M Mazzoni-Putman
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Javier Brumos
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Chengsong Zhao
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Jose M Alonso
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Anna N Stepanova
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
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18
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Jiang C, Li B, Song Z, Zhang Y, Yu C, Wang H, Wang L, Zhang H. PtBRI1.2 promotes shoot growth and wood formation through a brassinosteroid-mediated PtBZR1-PtWNDs module in poplar. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:6350-6364. [PMID: 34089602 DOI: 10.1093/jxb/erab260] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 06/04/2021] [Indexed: 06/12/2023]
Abstract
Brassinosteroid-insensitive-1 (BRI1) plays important roles in various signalling pathways controlling plant growth and development. However, the regulatory mechanism of BRI1 in brassinosteroid (BR)-mediated signalling for shoot growth and wood formation in woody plants is largely unknown. In this study, PtBRI1.2, a brassinosteroid-insensitive-1 gene, was overexpressed in poplar. Shoot growth and wood formation of transgenic plants were examined and the regulatory genes involved were verified. PtBRI1.2 was localized to the plasma membrane, with a predominant expression in leaves. Ectopic expression of PtBRI1.2 in Arabidopsis bri1-201 and bri1-5 mutants rescued their retarded-growth phenotype. Overexpression of PtBRI1.2 in poplar promoted shoot growth and wood formation in transgenic plants. Further studies revealed that overexpression of PtBRI1.2 promoted the accumulation of PtBZR1 (BRASSINAZOLE RESISTANT1) in the nucleus, which subsequently activated PtWNDs (WOOD-ASSOCIATED NAC DOMAIN transcription factors) to up-regulate expression of secondary cell wall biosynthesis genes involved in wood formation. Our results suggest that PtBRI1.2 plays a crucial role in regulating shoot growth and wood formation by activating BR signalling.
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Affiliation(s)
- Chunmei Jiang
- The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai, China
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Bei Li
- The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai, China
- The Key Laboratory of Molecular Module-Based Breeding of High Yield and abiotic Resistant Plants in the Universities of Shandong, and Institute for Advanced Study of Coastal Ecology, Ludong University, Yantai, China
| | - Zhizhong Song
- The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai, China
- The Key Laboratory of Molecular Module-Based Breeding of High Yield and abiotic Resistant Plants in the Universities of Shandong, and Institute for Advanced Study of Coastal Ecology, Ludong University, Yantai, China
| | - Yuliang Zhang
- Hainan Key Laboratory for Biosafety Monitoring and Molecular Breeding in Off-Season Reproduction Regions, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Chunyan Yu
- The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai, China
- The Key Laboratory of Molecular Module-Based Breeding of High Yield and abiotic Resistant Plants in the Universities of Shandong, and Institute for Advanced Study of Coastal Ecology, Ludong University, Yantai, China
| | - Haihai Wang
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Limin Wang
- The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai, China
- The Key Laboratory of Molecular Module-Based Breeding of High Yield and abiotic Resistant Plants in the Universities of Shandong, and Institute for Advanced Study of Coastal Ecology, Ludong University, Yantai, China
- Hainan Key Laboratory for Biosafety Monitoring and Molecular Breeding in Off-Season Reproduction Regions, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Hongxia Zhang
- The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai, China
- The Key Laboratory of Molecular Module-Based Breeding of High Yield and abiotic Resistant Plants in the Universities of Shandong, and Institute for Advanced Study of Coastal Ecology, Ludong University, Yantai, China
- Hainan Key Laboratory for Biosafety Monitoring and Molecular Breeding in Off-Season Reproduction Regions, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
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19
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Wang D, Chen Y, Li W, Li Q, Lu M, Zhou G, Chai G. Vascular Cambium: The Source of Wood Formation. FRONTIERS IN PLANT SCIENCE 2021; 12:700928. [PMID: 34484265 PMCID: PMC8416278 DOI: 10.3389/fpls.2021.700928] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/27/2021] [Indexed: 05/29/2023]
Abstract
Wood is the most abundant biomass produced by land plants and is mainly used for timber, pulping, and paper making. Wood (secondary xylem) is derived from vascular cambium, and its formation encompasses a series of developmental processes. Extensive studies in Arabidopsis and trees demonstrate that the initiation of vascular stem cells and the proliferation and differentiation of the cambial derivative cells require a coordination of multiple signals, including hormones and peptides. In this mini review, we described the recent discoveries on the regulation of the three developmental processes by several signals, such as auxin, cytokinins, brassinosteroids, gibberellins, ethylene, TDIF peptide, and their cross talk in Arabidopsis and Populus. There exists a similar but more complex regulatory network orchestrating vascular cambium development in Populus than that in Arabidopsis. We end up with a look at the future research prospects of vascular cambium in perennial woody plants, including interfascicular cambium development and vascular stem cell regulation.
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Affiliation(s)
- Dian Wang
- College of Agronomy, Qingdao Agricultural University, Qingdao, China
| | - Yan Chen
- College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, China
| | - Wei Li
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
| | - Quanzi Li
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
| | - Mengzhu Lu
- State Key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, China
| | - Gongke Zhou
- College of Resources and Environment, Qingdao Agricultural University, Qingdao, China
| | - Guohua Chai
- College of Resources and Environment, Qingdao Agricultural University, Qingdao, China
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20
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Fan F, Zhou Z, Qin H, Tan J, Ding G. Exogenous Brassinosteroid Facilitates Xylem Development in Pinus massoniana Seedlings. Int J Mol Sci 2021; 22:ijms22147615. [PMID: 34299234 PMCID: PMC8303313 DOI: 10.3390/ijms22147615] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/11/2021] [Accepted: 07/14/2021] [Indexed: 12/28/2022] Open
Abstract
Brassinosteroids (BRs) are known to be essential regulators for wood formation in herbaceous plants and poplar, but their roles in secondary growth and xylem development are still not well-defined, especially in pines. Here, we treated Pinus massoniana seedlings with different concentrations of exogenous BRs, and assayed the effects on plant growth, xylem development, endogenous phytohormone contents and gene expression within stems. Application of exogenous BR resulted in improving development of xylem more than phloem, and promoting xylem development in a dosage-dependent manner in a certain concentration rage. Endogenous hormone determination showed that BR may interact with other phytohormones in regulating xylem development. RNA-seq analysis revealed that some conventional phenylpropanoid biosynthesis- or lignin synthesis-related genes were downregulated, but the lignin content was elevated, suggesting that new lignin synthesis pathways or other cell wall components should be activated by BR treatment in P. massoniana. The results presented here reveal the foundational role of BRs in regulating plant secondary growth, and provide the basis for understanding molecular mechanisms of xylem development in P. massoniana.
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Affiliation(s)
- Fuhua Fan
- Institute for Forest Resources and Environment of Guizhou, Guizhou University, Guiyang 550025, China; (Z.Z.); (H.Q.)
- Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, Guizhou University, Guiyang 550025, China
- College of Forestry, Guizhou University, Guiyang 550025, China
- Correspondence: (F.F.); (G.D.)
| | - Zijing Zhou
- Institute for Forest Resources and Environment of Guizhou, Guizhou University, Guiyang 550025, China; (Z.Z.); (H.Q.)
- Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, Guizhou University, Guiyang 550025, China
- College of Forestry, Guizhou University, Guiyang 550025, China
| | - Huijuan Qin
- Institute for Forest Resources and Environment of Guizhou, Guizhou University, Guiyang 550025, China; (Z.Z.); (H.Q.)
- Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, Guizhou University, Guiyang 550025, China
- College of Forestry, Guizhou University, Guiyang 550025, China
| | - Jianhui Tan
- Timber Forest Research Institute, Guangxi Academy of Forestry, Nanning 530009, China;
| | - Guijie Ding
- Institute for Forest Resources and Environment of Guizhou, Guizhou University, Guiyang 550025, China; (Z.Z.); (H.Q.)
- Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province, Guizhou University, Guiyang 550025, China
- College of Forestry, Guizhou University, Guiyang 550025, China
- Correspondence: (F.F.); (G.D.)
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21
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Starodubtseva A, Kalachova T, Iakovenko O, Stoudková V, Zhabinskii V, Khripach V, Ruelland E, Martinec J, Burketová L, Kravets V. BODIPY Conjugate of Epibrassinolide as a Novel Biologically Active Probe for In Vivo Imaging. Int J Mol Sci 2021; 22:3599. [PMID: 33808421 PMCID: PMC8036458 DOI: 10.3390/ijms22073599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 11/17/2022] Open
Abstract
Brassinosteroids (BRs) are plant hormones of steroid nature, regulating various developmental and adaptive processes. The perception, transport, and signaling of BRs are actively studied nowadays via a wide range of biochemical and genetic tools. However, most of the knowledge about BRs intracellular localization and turnover relies on the visualization of the receptors or cellular compartments using dyes or fluorescent protein fusions. We have previously synthesized a conjugate of epibrassinolide with green fluorescent dye BODIPY (eBL-BODIPY). Here we present a detailed assessment of the compound bioactivity and its suitability as probe for in vivo visualization of BRs. We show that eBL-BODIPY rapidly penetrates epidermal cells of Arabidopsis thaliana roots and after long exposure causes physiological and transcriptomic responses similar to the natural hormone.
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Affiliation(s)
- Anastasiia Starodubtseva
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague, Czech Republic
- Institute of Ecology and Environmental Sciences of Paris, Paris-Est University, UPEC, 94010 Créteil, France
| | - Tetiana Kalachova
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
| | - Oksana Iakovenko
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, 02094 Kyiv, Ukraine;
| | - Vera Stoudková
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
| | - Vladimir Zhabinskii
- Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus, Kuprevich Str., 5/2, 220141 Minsk, Belarus; (V.Z.); (V.K.)
| | - Vladimir Khripach
- Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus, Kuprevich Str., 5/2, 220141 Minsk, Belarus; (V.Z.); (V.K.)
| | - Eric Ruelland
- UMR 7025 CNRS, GEC Génie Enzymatique et Cellulaire, Centre de Recherches, Rue Personne de Roberval, CS 60319, Alliance Sorbonne Universités, Université de Technologie de Compiègne, 60203 Compiègne CEDEX, France;
| | - Jan Martinec
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
| | - Lenka Burketová
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
| | - Volodymyr Kravets
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, 02094 Kyiv, Ukraine;
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22
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Liu J, Wang Z, Zhao J, Zhao L, Wang L, Su Z, Wei J. HrCYP90B1 modulating brassinosteroid biosynthesis in sea buckthorn (Hippophae rhamnoides L.) against fruit fly (Rhagoletis batava obseuriosa Kol.) infection. TREE PHYSIOLOGY 2021; 41:444-459. [PMID: 33238299 DOI: 10.1093/treephys/tpaa164] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/21/2020] [Accepted: 11/18/2020] [Indexed: 06/11/2023]
Abstract
Sea buckthorn is an important ecological and economic tree species, and its berries have been severely damaged by sea buckthorn fruit fly, Rhagoletis batava obseuriosa Kol. (Diptera: Tephritidae) (RBO). Brassinosteroid (BR) is widely involved in stress tolerance of plant. However, limited knowledge exists regarding the molecular mechanisms underlying insect resistance. Here, we found that BR content was much higher in sea buckthorn fruits with RBO infection than non-infection, and the damage rates of fruit with BR treatment were significantly lower than that of non-treatment. It indicated that BR could enhance RBO resistance in sea buckthorn. Several BR biosynthesis-related HrCYPs genes (CYP85A1/85A2/90A1/90B1/90C1/90D1/92A6/724B/734A1) were obtained and identified based on transcriptome analysis, of which the most up-regulated gene in fruits was HrCYP90B1 under RBO and mechanical damage. Overexpression of HrCYP90B1 in Arabidopsis thaliana showed BR and salicylic acid (SA) content was significantly increased, and the substrate campesterol (CR) of HrCYP90B1 content decreased. Further studies revealed that silencing HrCYP90B1 by virus-induced gene silencing resulted in decrease of BR, SA and defense-related enzymes contents, and increase of CR content. Silencing HrCYP90B1 also caused suppression of SA and activation of jasmonic acid pathways, enabling enhanced RBO susceptibility and more damage of fruits. Taken together, we obtained evidence that HrCYP90B1 was a positive regulator in RBO resistance improvement in sea buckthorn, which will provide comprehensive insights into the tree defense system of sea buckthorn to pest infection.
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Affiliation(s)
- Jianfeng Liu
- School of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Zhaoyu Wang
- School of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Jie Zhao
- School of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Lin Zhao
- School of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Lei Wang
- Hebei Research Center for Geoanalysis, Baoding 071051, China
| | - Zhi Su
- Desert Forest Experimental Center, Chinese Academy of Forestry, Dengkou 015200, China
| | - Jianrong Wei
- School of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
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23
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Overexpression of PtoCYCD3;3 Promotes Growth and Causes Leaf Wrinkle and Branch Appearance in Populus. Int J Mol Sci 2021; 22:ijms22031288. [PMID: 33525476 PMCID: PMC7866192 DOI: 10.3390/ijms22031288] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 12/18/2022] Open
Abstract
D-type cyclin (cyclin D, CYCD), combined with cyclin-dependent kinases (CDKs), participates in the regulation of cell cycle G1/S transition and plays an important role in cell division and proliferation. CYCD could affect the growth and development of herbaceous plants, such as Arabidopsis thaliana, by regulating the cell cycle process. However, its research in wood plants (e.g., poplar) is poor. Phylogenetic analysis showed that in Populus trichocarpa, CYCD3 genes expanded to six members, namely PtCYCD3;1–6. P. tomentosa CYCD3 genes were amplified based on the CDS region of P. trichocarpa CYCD3 genes. PtoCYCD3;3 showed the highest expression in the shoot tip, and the higher expression in young leaves among all members. Therefore, this gene was selected for further study. The overexpression of PtoCYCD3;3 in plants demonstrated obvious morphological changes during the observation period. The leaves became enlarged and wrinkled, the stems thickened and elongated, and multiple branches were formed by the plants. Anatomical study showed that in addition to promoting the differentiation of cambium tissues and the expansion of stem vessel cells, PtoCYCD3;3 facilitated the division of leaf adaxial epidermal cells and palisade tissue cells. Yeast two-hybrid experiment exhibited that 12 PtoCDK proteins could interact with PtoCYCD3;3, of which the strongest interaction strength was PtoCDKE;2, whereas the weakest was PtoCDKG;3. Molecular docking experiments further verified the force strength of PtoCDKE;2 and PtoCDKG;3 with PtoCYCD3;3. In summary, these results indicated that the overexpression of PtoCYCD3;3 significantly promoted the vegetative growth of Populus, and PtoCYCD3;3 may interact with different types of CDK proteins to regulate cell cycle processes.
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24
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Kreynes AE, Yong Z, Ellis BE. Developmental phenotypes of Arabidopsis plants expressing phosphovariants of AtMYB75. PLANT SIGNALING & BEHAVIOR 2021; 16:1836454. [PMID: 33100126 PMCID: PMC7781762 DOI: 10.1080/15592324.2020.1836454] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The Arabidopsis transcription factor Myeloblastosis protein 75 (MYB75, AT1G56650) is a well-established transcriptional activator of genes required for anthocyanin and flavonoid production, and a repressor of lignin and other secondary cell wall biosynthesis genes. MYB75 is itself tightly regulated at the transcriptional, translational and post-translational levels, including protein phosphorylation by Arabidopsis MAP kinases Examination of the behavior of different phosphovariant versions of MYB75 in vitro and in vivo revealed that overexpression of the MYB75T131E phosphovariant had a particularly marked effect on global changes in gene expression suggesting that phosphorylated MYB75 could be involved in a broader range of functions than previously recognized. Here, we describe a range of distinct developmental phenotypes observed among Arabidopsis lines expressing various phosphovariant forms of MYB75. Expression of either MYB75T131E or MYB75T131A phosphovariants, from the endogenous MYB75 promoter, in Arabidopsis myb75- mutants (Nossen background), resulted in severely impaired germination rates, and developmental arrest at early seedling stages. Arabidopsis plants overexpressing MYB75T131E from a strong constitutive Cauliflower mosaic virus (CaMV35S) promoter displayed slower development, with delayed bolting, flowering and onset of senescence. Conversely, MYB75T131A -overexpressing lines flowered and set seed earlier than either Col-0 WT controls or other MYB75-overexpressors (MYB75WT and MYB75T131E ). Histochemical analysis of mature stems also revealed ectopic vessel development in plants overexpressing MYB75; this phenotype was particularly prominent in the MYB75T131E phosphovariant. These data suggest that MYB75 plays a significant role in plant development, and that this aspect of MYB75 function is influenced by its phosphorylation status.
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Affiliation(s)
- Anna E. Kreynes
- Michael Smith Laboratories, Department of Botany, University of British Columbia, Vancouver, Canada
- CONTACT Anna E. Kreynes Michael Smith Laboratories, Department of Botany, University of British Columbia, Vancouver, Canada
| | - Zhenhua Yong
- Michael Smith Laboratories, Department of Botany, University of British Columbia, Vancouver, Canada
| | - Brian E. Ellis
- Michael Smith Laboratories, Department of Botany, University of British Columbia, Vancouver, Canada
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25
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Wang P, Wang T, Han J, Li M, Zhao Y, Su T, Ma C. Plant Autophagy: An Intricate Process Controlled by Various Signaling Pathways. FRONTIERS IN PLANT SCIENCE 2021; 12:754982. [PMID: 34630498 PMCID: PMC8495024 DOI: 10.3389/fpls.2021.754982] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 08/31/2021] [Indexed: 05/17/2023]
Abstract
Autophagy is a ubiquitous process used widely across plant cells to degrade cellular material and is an important regulator of plant growth and various environmental stress responses in plants. The initiation and dynamics of autophagy in plant cells are precisely controlled according to the developmental stage of the plant and changes in the environment, which are transduced into intracellular signaling pathways. These signaling pathways often regulate autophagy by mediating TOR (Target of Rapamycin) kinase activity, an important regulator of autophagy initiation; however, some also act via TOR-independent pathways. Under nutrient starvation, TOR activity is suppressed through glucose or ROS (reactive oxygen species) signaling, thereby promoting the initiation of autophagy. Under stresses, autophagy can be regulated by the regulatory networks connecting stresses, ROS and plant hormones, and in turn, autophagy regulates ROS levels and hormone signaling. This review focuses on the latest research progress in the mechanism of different external signals regulating autophagy.
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26
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Hwang H, Lee HY, Ryu H, Cho H. Functional Characterization of BRASSINAZOLE-RESISTANT 1 in Panax Ginseng ( PgBZR1) and Brassinosteroid Response during Storage Root Formation. Int J Mol Sci 2020; 21:ijms21249666. [PMID: 33352948 PMCID: PMC7766047 DOI: 10.3390/ijms21249666] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/09/2020] [Accepted: 12/15/2020] [Indexed: 11/17/2022] Open
Abstract
Brassinosteroids (BRs) play crucial roles in the physiology and development of plants. In the model plant Arabidopsis, BR signaling is initiated at the level of membrane receptors, BRASSINOSTEROIDS INSENSITIVE 1 (BRI1) and BRI1-ASSOCIATED RECEPTOR KINASE 1 (BAK1) complex, thus activating the transcription factors (TFs) BRASSINAZOLE RESISTANT 1/BRI1-EMS-SUPPRESSOR 1 (BZR1/BES1) to coordinate BR responsive genes. BRASSINOSTEROIDS INSENSITIVE 2 (BIN2), glycogen synthase kinase 3 (GSK3) like-kinase, negatively regulates BZR1/BES1 transcriptional activity through phosphorylation-dependent cytosolic retention and shuttling. However, it is still unknown whether this mechanism is conserved in Panax ginseng C. A. Mayer, a member of the Araliaceae family, which is a shade-tolerant perennial root crop. Despite its pharmacological and agricultural importance, the role of BR signaling in the development of P. ginseng and characterization of BR signaling components are still elusive. In this study, by utilizing the Arabidopsisbri1 mutant, we found that ectopic expression of the gain of function form of PgBZR1 (Pgbzr1-1D) restores BR deficiency. In detail, ectopic expression of Pgbzr1-1D rescues dwarfism, defects of floral organ development, and hypocotyl elongation of bri1-5, implying the functional conservation of PgBZR1 in P. ginseng. Interestingly, brassinolide (BL) and BRs biosynthesis inhibitor treatment in two-year-old P. ginseng storage root interferes with and promotes, respectively, secondary growth in terms of xylem formation. Altogether, our results provide new insight into the functional conservation and potential diversification of BR signaling and response in P. ginseng.
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Affiliation(s)
- Hyeona Hwang
- Department of Biology, College of Natural Sciences, Chungbuk National University, Cheongju 28644, Korea;
| | - Hwa-Yong Lee
- Department of Forest Science, College of Agriculture, Life & Environmental Sciences, Chungbuk National University, Cheongju 28644, Korea;
| | - Hojin Ryu
- Department of Biology, College of Natural Sciences, Chungbuk National University, Cheongju 28644, Korea;
- Correspondence: (H.R.); (H.C.)
| | - Hyunwoo Cho
- Department of Industrial Plant Science & Technology, College of Agriculture, Life & Environmental Sciences, Chungbuk National University, Cheongju 28644, Korea
- Correspondence: (H.R.); (H.C.)
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27
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Mugume Y, Kazibwe Z, Bassham DC. Target of Rapamycin in Control of Autophagy: Puppet Master and Signal Integrator. Int J Mol Sci 2020; 21:ijms21218259. [PMID: 33158137 PMCID: PMC7672647 DOI: 10.3390/ijms21218259] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/01/2020] [Accepted: 11/03/2020] [Indexed: 02/06/2023] Open
Abstract
The target of rapamycin (TOR) is an evolutionarily-conserved serine/threonine kinase that senses and integrates signals from the environment to coordinate developmental and metabolic processes. TOR senses nutrients, hormones, metabolites, and stress signals to promote cell and organ growth when conditions are favorable. However, TOR is inhibited when conditions are unfavorable, promoting catabolic processes such as autophagy. Autophagy is a macromolecular degradation pathway by which cells degrade and recycle cytoplasmic materials. TOR negatively regulates autophagy through phosphorylation of ATG13, preventing activation of the autophagy-initiating ATG1-ATG13 kinase complex. Here we review TOR complex composition and function in photosynthetic and non-photosynthetic organisms. We also review recent developments in the identification of upstream TOR activators and downstream effectors of TOR. Finally, we discuss recent developments in our understanding of the regulation of autophagy by TOR in photosynthetic organisms.
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28
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Ren R, Yang X, Song A, Li C, Yang H, Kang Y. Control of Phytophthora melonis damping-off treated with 24-epibrassinolide and a histological study of cucumber hypocotyl. PROTOPLASMA 2020; 257:1519-1529. [PMID: 32621043 DOI: 10.1007/s00709-020-01523-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 06/12/2020] [Indexed: 06/11/2023]
Abstract
The oomycete Phytophthora melonis causes a severe disease in cucumber plants in Asia. In this study, the diameter of cucumber hypocotyl in the resistant variety 'Shantou qing gua' was significantly larger than that of the susceptible variety 'Zhongnong No. 20'. The significantly lower incidence of disease and less invasive hyphae on the epidermis and transverse section of hypocotyls in P plants of the resistant variety than those in susceptible cultivars were also observed. Brassinosteroids are a class of phytohormones that affect plant growth and development and are involved in regulating plant resistance to a variety of biotic and abiotic stresses. 24-Epibrassinolide root drenching significantly enhanced the thickening of cucumber hypocotyl. Thick hypocotyls showed strong resistance to P. melonis, indicating that it significantly reduced the incidence of disease and retarded the hyphae extension for both resistant and susceptible cucumbers. 24-Epibrassinolide pretreatment had no significant effect on the elongation of cucumber hypocotyl. Further histological observation showed that under the condition of infection with P. melonis, exogenous 24-epibrassinolide could induce lignin deposition in external phloem and xylem vessel cell wall of the cucumber hypocotyl vascular bundle. There is also an accumulation of callose in the external phloem sieve plate, which activates the resistance responses in cell walls. It is worth mentioning that in both inoculated and uninoculated conditions, exogenous 24-epibrassinolide enhanced lignin formation in external phloem and xylem vessel cell wall of the vascular bundle. This increased the content of lignin in hypocotyl as well as the number of vascular bundles in the hypocotyl base. The above results show that 24-epibrassinolide constitutively regulates the thickening of cucumber hypocotyl and the development of vascular bundle, hence preventing phytophthora infection and inducing plant resistance to disease.
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Affiliation(s)
- Rongrong Ren
- College of Horticulture, South China Agricultural University, Guangzhou, 510642, People's Republic of China
| | - Xian Yang
- College of Horticulture, South China Agricultural University, Guangzhou, 510642, People's Republic of China
| | - Aiting Song
- College of Horticulture, South China Agricultural University, Guangzhou, 510642, People's Republic of China
| | - Chenchen Li
- College of Horticulture, South China Agricultural University, Guangzhou, 510642, People's Republic of China
| | - Haijun Yang
- Center of Experimental Teaching for Common Basic Courses, South China Agricultural University, Guangzhou, 510642, People's Republic of China.
| | - Yunyan Kang
- College of Horticulture, South China Agricultural University, Guangzhou, 510642, People's Republic of China.
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29
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Li T, Kang X, Lei W, Yao X, Zou L, Zhang D, Lin H. SHY2 as a node in the regulation of root meristem development by auxin, brassinosteroids, and cytokinin. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2020; 62:1500-1517. [PMID: 32239656 DOI: 10.1111/jipb.12931] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/25/2020] [Indexed: 05/27/2023]
Abstract
In multicellular organisms, the balance between cell division and differentiation determines organ size, and represents a central unknown in developmental biology. In Arabidopsis roots, this balance is mediated between cytokinin and auxin through a regulatory circuit converging on the IAA3/SHORT HYPOCOTYL 2 (SHY2) gene. Here, we show that crosstalk between brassinosteroids (BRs) and auxin occurs in the vascular transition zone to promote root meristem development. We found that BR increases root meristem size by up-regulating expression of the PINFORMED 7 (PIN7) gene and down-regulating expression of the SHY2 gene. In addition, BES1 could directly bind to the promoter regions of both PIN7 and SHY2, indicating that PIN7 and SHY2 mediate the BR-induced growth of the root meristem by serving as direct targets of BES1. Moreover, the PIN7 overexpression and loss-of-function SHY2 mutant were sensitive to the effects of BR and could partially suppress the short-root phenotypes associated with deficient BR signaling. Interestingly, BRs could inhibit the accumulation of SHY2 protein in response to cytokinin. Taken together, these findings suggest that a complex equilibrium model exists in which regulatory interactions among BRs, auxin, and cytokinin regulate optimal root growth.
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Affiliation(s)
- Taotao Li
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
- School of Life Science and Engineering, Henan University of Urban Construction, Pingdingshan, 467044, China
| | - Xinke Kang
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
| | - Wei Lei
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
| | - Xiuhong Yao
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
| | - Lijuan Zou
- Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianyang, 621000, China
| | - Dawei Zhang
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
| | - Honghui Lin
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China
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30
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Wu L, Zhao Y, Zhang Q, Chen Y, Gao M, Wang Y. Overexpression of the 3-hydroxy-3-methylglutaryl-CoA synthase gene LcHMGS effectively increases the yield of monoterpenes and sesquiterpenes. TREE PHYSIOLOGY 2020; 40:1095-1107. [PMID: 32325486 DOI: 10.1093/treephys/tpaa045] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 02/15/2020] [Accepted: 04/03/2020] [Indexed: 06/11/2023]
Abstract
Monoterpenes are important components of plant essential oils and have long been used as raw materials for spices and food flavorings. A number of studies have been performed to increase the content of monoterpenes in plants, but no obvious effect was observed. Exchange was observed between the methylerythritol phosphate (MEP) and mevalonic acid (MVA) metabolic pathways, which produce monoterpenes and sesquiterpenes, respectively. However, the specific details of the communication have not been elucidated. In the present study, we investigated the effects of overexpressing Litsea cubeba (Lour.) Persoon 3-hydroxy-3-methylglutaryl-coenzyme A synthase (LcHMGS) on the production of monoterpenes and sesquiterpenes. In addition, we also explored the flow of metabolic flux between the MEP and MVA pathways. We cloned LcHMGS and analyzed its expression pattern in various tissues. The overexpression of LcHMGS significantly increased the species and content of monoterpenes and sesquiterpenes. In addition, LcHMGS overexpression in plants induced such phenotypes as excessive growth, enlarged vegetative organs and early flowering by elevating the GA3 content. Our results demonstrate a metabolic engineering strategy to improve the yield of monoterpenes and sesquiterpenes and simultaneously increase the biomass of plants.
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Affiliation(s)
- Liwen Wu
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Xiangshan Rd, Beijing 100091, China
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Yunxiao Zhao
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Xiangshan Rd, Beijing 100091, China
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Qiyan Zhang
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Xiangshan Rd, Beijing 100091, China
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Yicun Chen
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Xiangshan Rd, Beijing 100091, China
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Ming Gao
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Xiangshan Rd, Beijing 100091, China
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
| | - Yangdong Wang
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Xiangshan Rd, Beijing 100091, China
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China
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31
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Zhang Z, Yang X, Cheng L, Guo Z, Wang H, Wu W, Shin K, Zhu J, Zheng X, Bian J, Li Y, Gu L, Zhu Q, Wang ZY, Wang W. Physiological and transcriptomic analyses of brassinosteroid function in moso bamboo (Phyllostachys edulis) seedlings. PLANTA 2020; 252:27. [PMID: 32712728 DOI: 10.1007/s00425-020-03432-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 07/17/2020] [Indexed: 06/11/2023]
Abstract
This study demonstrates that brassinosteroid is essential for seedling and shoot growth in moso bamboo. The shoot of moso bamboo is known to grow extremely fast. The roles of phytohormones in such fast growth of bamboo shoot remain unclear. Here we reported that endogenous brassinosteroid (BR) is a major factor promoting bamboo shoot internode elongation. Reducing endogenous brassinosteroid level by its biosynthesis inhibitor propiconazole stunted shoot growth in seedling stage, whereas exogenous BR application promoted scale leaf elongation and the inclination of lamina joint of leaves and scale leaves. Genome-wide transcriptome analysis identified hundreds of genes whose expression levels are altered by BR and propiconazole in shoots and roots of bamboo seedling. The data show that BR regulates cell wall-related genes, hydrogen peroxide catabolic genes, and auxin-related genes. Our study demonstrates an essential role of BR in fast growth bamboo shoots and identifies a large number of BR-responsive genes in bamboo seedlings.
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Affiliation(s)
- Zhe Zhang
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xuelian Yang
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Ling Cheng
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
- College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Zejun Guo
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Huiyuan Wang
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Weihuang Wu
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Kihye Shin
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Jinyao Zhu
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiaoli Zheng
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Jianghu Bian
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
- College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yangchen Li
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
- College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Lianfeng Gu
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Qiang Zhu
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Zhi-Yong Wang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Wenfei Wang
- Basic Forestry and Proteomics Research Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China.
- College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China.
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Li JW, Zhang SB, Xi HP, Bradshaw CJA, Zhang JL. Processes controlling programmed cell death of root velamen radicum in an epiphytic orchid. ANNALS OF BOTANY 2020; 126:261-275. [PMID: 32318689 PMCID: PMC7380463 DOI: 10.1093/aob/mcaa077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Accepted: 04/18/2020] [Indexed: 05/06/2023]
Abstract
BACKGROUND AND AIMS Development of the velamen radicum on the outer surface of the root epidermis is an important characteristic for water uptake and retention in some plant families, particularly epiphytic orchids, for survival under water-limited environments. Velamen radicum cells derive from the primary root meristem; however, following this development, velamen radicum cells die by incompletely understood processes of programmed cell death (PCD). METHODS We combined the use of transmission electron microscopy, X-ray micro-tomography and transcriptome methods to characterize the major anatomical and molecular changes that occur during the development and death of velamen radicum cells of Cymbidium tracyanum, a typical epiphytic orchid, to determine how PCD occurs. KEY RESULTS Typical changes of PCD in anatomy and gene expression were observed in the development of velamen radicum cells. During the initiation of PCD, we found that both cell and vacuole size increased, and several genes involved in brassinosteroid and ethylene pathways were upregulated. In the stage of secondary cell wall formation, significant anatomical changes included DNA degradation, cytoplasm thinning, organelle decrease, vacuole rupture and cell wall thickening. Changes were found in the expression of genes related to the biosynthesis of cellulose and lignin, which are instrumental in the formation of secondary cell walls, and are regulated by cytoskeleton-related factors and phenylalanine ammonia-lyase. In the final stage of PCD, cell autolysis was terminated from the outside to the inside of the velamen radicum. The regulation of genes related to autophagy, vacuolar processing enzyme, cysteine proteases and metacaspase was involved in the final execution of cell death and autolysis. CONCLUSIONS Our results showed that the development of the root velamen radicum in an epiphytic orchid was controlled by the process of PCD, which included initiation of PCD, followed by formation of the secondary cell wall, and execution of autolysis following cell death.
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Affiliation(s)
- Jia-Wei Li
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China
- Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan, China
| | - Shi-Bao Zhang
- Key Laboratory for Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- For correspondence. E-mail or
| | - Hui-Peng Xi
- Horticulture Department, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China
| | - Corey J A Bradshaw
- Global Ecology, College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, South Australia, Australia
| | - Jiao-Lin Zhang
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China
- Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan, China
- For correspondence. E-mail or
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MYB43 in Oilseed Rape ( Brassica napus) Positively Regulates Vascular Lignification, Plant Morphology and Yield Potential but Negatively Affects Resistance to Sclerotinia sclerotiorum. Genes (Basel) 2020; 11:genes11050581. [PMID: 32455973 PMCID: PMC7290928 DOI: 10.3390/genes11050581] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/18/2020] [Accepted: 05/20/2020] [Indexed: 11/17/2022] Open
Abstract
Arabidopsis thaliana MYB43 (AtMYB43) is suggested to be involved in cell wall lignification. PtrMYB152, the Populus orthologue of AtMYB43, is a transcriptional activator of lignin biosynthesis and vessel wall deposition. In this research, MYB43 genes from Brassica napus (rapeseed) and its parental species B. rapa and B. oleracea were molecularly characterized, which were dominantly expressed in stem and other vascular organs and showed responsiveness to Sclerotinia sclerotiorum infection. The BnMYB43 family was silenced by RNAi, and the transgenic rapeseed lines showed retardation in growth and development with smaller organs, reduced lodging resistance, fewer silique number and lower yield potential. The thickness of the xylem layer decreased by 28%; the numbers of sclerenchymatous cells, vessels, interfascicular fibers, sieve tubes and pith cells in the whole cross section of the stem decreased by 28%, 59%, 48%, 34% and 21% in these lines, respectively. The contents of cellulose and lignin decreased by 17.49% and 16.21% respectively, while the pectin content increased by 71.92% in stems of RNAi lines. When inoculated with S. sclerotiorum, the lesion length was drastically decreased by 52.10% in the stems of transgenic plants compared with WT, implying great increase in disease resistance. Correspondingly, changes in the gene expression patterns of lignin biosynthesis, cellulose biosynthesis, pectin biosynthesis, cell cycle, SA- and JA-signals, and defensive pathways were in accordance with above phenotypic modifications. These results show that BnMYB43, being a growth-defense trade-off participant, positively regulates vascular lignification, plant morphology and yield potential, but negatively affects resistance to S. sclerotiorum. Moreover, this lignification activator influences cell biogenesis of both lignified and non-lignified tissues of the whole vascular organ.
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Oh MH, Honey SH, Tax FE. The Control of Cell Expansion, Cell Division, and Vascular Development by Brassinosteroids: A Historical Perspective. Int J Mol Sci 2020; 21:ijms21051743. [PMID: 32143305 PMCID: PMC7084555 DOI: 10.3390/ijms21051743] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/10/2020] [Accepted: 02/22/2020] [Indexed: 12/21/2022] Open
Abstract
Steroid hormones are important signaling molecules in plants and animals. The plant steroid hormone brassinosteroids were first isolated and characterized in the 1970s and have been studied since then for their functions in plant growth. Treatment of plants or plant cells with brassinosteroids revealed they play important roles during diverse developmental processes, including control of cell expansion, cell division, and vascular differentiation. Molecular genetic studies, primarily in Arabidopsis thaliana, but increasingly in many other plants, have identified many genes involved in brassinosteroid biosynthesis and responses. Here we review the roles of brassinosteroids in cell expansion, cell division, and vascular differentiation, comparing the early physiological studies with more recent results of the analysis of mutants in brassinosteroid biosynthesis and signaling genes. A few representative examples of other molecular pathways that share developmental roles with brassinosteroids are described, including pathways that share functional overlap or response components with the brassinosteroid pathway. We conclude by briefly discussing the origin and conservation of brassinosteroid signaling.
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Affiliation(s)
- Man-Ho Oh
- Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon 34134, Korea;
| | - Saxon H. Honey
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA;
| | - Frans E. Tax
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA;
- Correspondence:
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Liu ZJ, Zhang YH, Ma XF, Ye P, Gao F, Li XF, Zhou YJ, Shi ZH, Cheng HM, Zheng CX, Li HJ, Zhang GF. Biological functions of Arabidopsis thaliana MBP-1-like protein encoded by ENO2 in the response to drought and salt stresses. PHYSIOLOGIA PLANTARUM 2020; 168:660-674. [PMID: 31343741 DOI: 10.1111/ppl.13013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 06/21/2019] [Accepted: 07/16/2019] [Indexed: 06/10/2023]
Abstract
Arabidopsis thaliana ENO2 (AtENO2) plays an important role in plant growth and development. It encodes two proteins, a full-length AtENO2 and a truncated version, AtMBP-1, alternatively translated from the second start codon of the mRNA. The AtENO2 mutant (eno2- ) exhibited reduced leaf size, shortened siliques, a dwarf phenotype and higher sensitivity to abiotic stress. The objectives of this study were to analyze the regulatory network of the ENO2 gene in plant growth development and understand the function of AtENO2/AtMBP-1 to abiotic stresses. An eno2- /35S:AtENO2-GFP line and an eno2- /35S:AtMBP-1-GFP line of Arabidopsis were obtained. Results of sequencing by 454 GS FLX identified 578 upregulated and 720 downregulated differential expressed genes (DEGs) in a pairwise comparison (WT-VS-eno2- ). All the high-quality reads were annotated using the Gene Ontology (GO) terms. The DEGs with KEGG pathway annotations occurred in 110 pathways. The metabolic pathways and biosynthesis of secondary metabolites contained more DEGs. Moreover, the eno2- /35S:AtENO2-GFP line returned to the wild-type (WT) phenotype and was tolerant to drought and salt stresses. However, the eno2- /35S:AtMBP-1-GFP line was not able to recover the WT phenotype but it has a higher tolerance to drought and salt stresses. Results from this study demonstrate that AtENO2 is critical for the growth and development, and the AtMBP-1 coded by AtENO2 is important in tolerance of Arabidopsis to abiotic stresses.
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Affiliation(s)
- Zi-Jin Liu
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yong-Hua Zhang
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Xiao-Feng Ma
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Pan Ye
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Fei Gao
- College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China
| | - Xiao-Feng Li
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yi-Jun Zhou
- College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China
| | - Zi-Han Shi
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Hui-Mei Cheng
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Chao-Xing Zheng
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Hong-Jie Li
- The National Engineering Laboratory of Crop Molecular Breeding, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Gen-Fa Zhang
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
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Wolf S. Deviating from the Beaten Track: New Twists in Brassinosteroid Receptor Function. Int J Mol Sci 2020; 21:ijms21051561. [PMID: 32106564 PMCID: PMC7084826 DOI: 10.3390/ijms21051561] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/21/2020] [Accepted: 02/22/2020] [Indexed: 12/15/2022] Open
Abstract
A key feature of plants is their plastic development tailored to the environmental conditions. To integrate environmental signals with genetic growth regulatory programs, plants rely on a number of hormonal pathways, which are intimately connected at multiple levels. Brassinosteroids (BRs), a class of plant sterol hormones, are perceived by cell surface receptors and trigger responses instrumental in tailoring developmental programs to environmental cues. Arguably, BR signalling is one of the best-characterized plant signalling pathways, and the molecular composition of the core signal transduction cascade seems clear. However, BR research continues to reveal new twists to re-shape our view on this key signalling circuit. Here, exciting novel findings pointing to the plasma membrane as a key site for BR signalling modulation and integration with other pathways are reviewed and new inputs into the BR signalling pathway and emerging “non-canonical” functions of the BR receptor complex are highlighted. Together, this new evidence underscores the complexity of plant signalling integration and serves as a reminder that highly-interconnected signalling pathways frequently comprise non-linear aspects which are difficult to convey in classical conceptual models.
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Affiliation(s)
- Sebastian Wolf
- Centre for Organismal Studies (COS) Heidelberg, INF230, 69120 Heidelberg, Germany
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Molecular Evidences for the Interactions of Auxin, Gibberellin, and Cytokinin in Bent Peduncle Phenomenon in Rose ( Rosa sp.). Int J Mol Sci 2020; 21:ijms21041360. [PMID: 32085472 PMCID: PMC7072929 DOI: 10.3390/ijms21041360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/08/2020] [Accepted: 02/14/2020] [Indexed: 12/03/2022] Open
Abstract
In roses (Rosa sp.), peduncle morphology is an important ornamental feature. The common physiological abnormality known as the bent peduncle phenomenon (BPP) seriously decreases the quality of rose flowers and thus the commercial value. Because the molecular mechanisms underlying this condition are poorly understood, we analysed the transcriptional profiles and cellular structures of bent rose peduncles. Numerous differentially expressed genes involved in the auxin, cytokinin, and gibberellin signaling pathways were shown to be associated with bent peduncle. Paraffin sections showed that the cell number on the upper sides of bent peduncles was increased, while the cells on the lower sides were larger than those in normal peduncles. We also investigated the large, deformed sepals that usually accompany BPP and found increased expression level of some auxin-responsive genes and decreased expression level of genes that are involved in cytokinin and gibberellin synthesis in these sepals. Furthermore, removal of the deformed sepals partially relieved BPP. In summary, our findings suggest that auxin, cytokinin, and gibberellin all influence the development of BPP by regulating cell division and expansion. To effectively reduce BPP in roses, more efforts need to be devoted to the molecular regulation of gibberellins and cytokinins in addition to that of auxin.
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Ackerman-Lavert M, Savaldi-Goldstein S. Growth models from a brassinosteroid perspective. CURRENT OPINION IN PLANT BIOLOGY 2020; 53:90-97. [PMID: 31809963 DOI: 10.1016/j.pbi.2019.10.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/17/2019] [Accepted: 10/21/2019] [Indexed: 05/19/2023]
Abstract
Plant growth relies on interconnected hormonal pathways, their corresponding transcriptional networks and mechanical signals. This work reviews recent brassinosteroid (BR) studies and integrates them with current growth models derived from research in roots. The relevance of spatiotemporal BR signaling in the longitudinal and radial root axes and its multifaceted interaction with auxin, the impact of BR on final cell size determination and its interplay with microtubules and the cell wall are discussed. Also highlighted are emerging variations of canonical BR signaling that could function in developmental-specific context.
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Wang H. Regulation of vascular cambium activity. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 291:110322. [PMID: 31928672 DOI: 10.1016/j.plantsci.2019.110322] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 09/25/2019] [Accepted: 10/24/2019] [Indexed: 05/04/2023]
Abstract
Vascular cambium contributes to lateral growth in dicotyledonous plants and gymnosperms. Physiological, genetics and molecular studies indicate that cambial activity is regulated by a combination of long-distance hormonal signals and short-range peptide signaling pathways. Communication from endodermis and phloem tissues also affects cambial stem cell proliferation. Interactions between these signaling pathways provide flexibility for vascular development. In this mini-review, we discuss the new findings in long- and short-range signaling pathways in regulating vascular cambium proliferation and provide future perspectives in the cambium research. Deep imaging and mathematical modeling will help further dissecting the functional mechanisms of cambial activity control.
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Affiliation(s)
- Huanzhong Wang
- Department of Plant Science and Landscape Architecture, University of Connecticut, 1376 Storrs Rd, Storrs, CT 06269, United States.
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40
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Du J, Gerttula S, Li Z, Zhao ST, Liu YL, Liu Y, Lu MZ, Groover AT. Brassinosteroid regulation of wood formation in poplar. THE NEW PHYTOLOGIST 2020; 225:1516-1530. [PMID: 31120133 DOI: 10.1111/nph.15936] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 04/30/2019] [Indexed: 05/06/2023]
Abstract
Brassinosteroids have been implicated in the differentiation of vascular cell types in herbaceous plants, but their roles during secondary growth and wood formation are not well defined. Here we pharmacologically and genetically manipulated brassinosteroid levels in poplar trees and assayed the effects on secondary growth and wood formation, and on gene expression within stems. Elevated brassinosteroid levels resulted in increases in secondary growth and tension wood formation, while inhibition of brassinosteroid synthesis resulted in decreased growth and secondary vascular differentiation. Analysis of gene expression showed that brassinosteroid action is positively associated with genes involved in cell differentiation and cell-wall biosynthesis. The results presented here show that brassinosteroids play a foundational role in the regulation of secondary growth and wood formation, in part through the regulation of cell differentiation and secondary cell wall biosynthesis.
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Affiliation(s)
- Juan Du
- College of Life Sciences, Zhejiang University, 866 Yu Hang tang Road, Hangzhou, 310058, China
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
- Pacific Southwest Research Station, US Forest Service, Davis, CA, 95618, USA
| | - Suzanne Gerttula
- Pacific Southwest Research Station, US Forest Service, Davis, CA, 95618, USA
| | - Zehua Li
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
| | - Shu-Tang Zhao
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
| | - Ying-Li Liu
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
| | - Yu Liu
- College of Life Sciences, Zhejiang University, 866 Yu Hang tang Road, Hangzhou, 310058, China
| | - Meng-Zhu Lu
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China
- State Key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang Agriculture and Forest University, Hangzhou, 311300, China
| | - Andrew T Groover
- Pacific Southwest Research Station, US Forest Service, Davis, CA, 95618, USA
- Department of Plant Biology, University of California Davis, Davis, CA, 95616, USA
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Fan C, Yu H, Qin S, Li Y, Alam A, Xu C, Fan D, Zhang Q, Wang Y, Zhu W, Peng L, Luo K. Brassinosteroid overproduction improves lignocellulose quantity and quality to maximize bioethanol yield under green-like biomass process in transgenic poplar. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:9. [PMID: 31988661 PMCID: PMC6969456 DOI: 10.1186/s13068-020-1652-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 01/06/2020] [Indexed: 05/19/2023]
Abstract
BACKGROUND As a leading biomass feedstock, poplar plants provide enormous lignocellulose resource convertible for biofuels and bio-chemicals. However, lignocellulose recalcitrance particularly in wood plants, basically causes a costly bioethanol production unacceptable for commercial marketing with potential secondary pollution to the environment. Therefore, it becomes important to reduce lignocellulose recalcitrance by genetic modification of plant cell walls, and meanwhile to establish advanced biomass process technology in woody plants. Brassinosteroids, plant-specific steroid hormones, are considered to participate in plant growth and development for biomass production, but little has been reported about brassinosteroids roles in plant cell wall assembly and modification. In this study, we generated transgenic poplar plant that overexpressed DEETIOLATED2 gene for brassinosteroids overproduction. We then detected cell wall feature alteration and examined biomass enzymatic saccharification for bioethanol production under various chemical pretreatments. RESULTS Compared with wild type, the PtoDET2 overexpressed transgenic plants contained much higher brassinosteroids levels. The transgenic poplar also exhibited significantly enhanced plant growth rate and biomass yield by increasing xylem development and cell wall polymer deposition. Meanwhile, the transgenic plants showed significantly improved lignocellulose features such as reduced cellulose crystalline index and degree of polymerization values and decreased hemicellulose xylose/arabinose ratio for raised biomass porosity and accessibility, which led to integrated enhancement on biomass enzymatic saccharification and bioethanol yield under various chemical pretreatments. In contrast, the CRISPR/Cas9-generated mutation of PtoDET2 showed significantly lower brassinosteroids level for reduced biomass saccharification and bioethanol yield, compared to the wild type. Notably, the optimal green-like pretreatment could even achieve the highest bioethanol yield by effective lignin extraction in the transgenic plant. Hence, this study proposed a mechanistic model elucidating how brassinosteroid regulates cell wall modification for reduced lignocellulose recalcitrance and increased biomass porosity and accessibility for high bioethanol production. CONCLUSIONS This study has demonstrated a powerful strategy to enhance cellulosic bioethanol production by regulating brassinosteroid biosynthesis for reducing lignocellulose recalcitrance in the transgenic poplar plants. It has also provided a green-like process for biomass pretreatment and enzymatic saccharification in poplar and beyond.
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Affiliation(s)
- Chunfen Fan
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, Institute of Resources Botany, School of Life Sciences, Southwest University, Chongqing, 400715 China
| | - Hua Yu
- Biomass & Bioenergy Research Centre, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Shifei Qin
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, Institute of Resources Botany, School of Life Sciences, Southwest University, Chongqing, 400715 China
| | - Yongli Li
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, Institute of Resources Botany, School of Life Sciences, Southwest University, Chongqing, 400715 China
| | - Aftab Alam
- Biomass & Bioenergy Research Centre, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Changzhen Xu
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, Institute of Resources Botany, School of Life Sciences, Southwest University, Chongqing, 400715 China
| | - Di Fan
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, Institute of Resources Botany, School of Life Sciences, Southwest University, Chongqing, 400715 China
| | - Qingwei Zhang
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, Institute of Resources Botany, School of Life Sciences, Southwest University, Chongqing, 400715 China
| | - Yanting Wang
- Biomass & Bioenergy Research Centre, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Wanbin Zhu
- College of Biomass Sciences and Engineering, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193 China
| | - Liangcai Peng
- Biomass & Bioenergy Research Centre, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070 China
- College of Biomass Sciences and Engineering, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193 China
| | - Keming Luo
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, Institute of Resources Botany, School of Life Sciences, Southwest University, Chongqing, 400715 China
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Tang X, Wang C, Liu Y, He G, Ma N, Chai G, Li S, Xu H, Zhou G. Brassinosteroid Signaling Converges With Auxin-Mediated C3H17 to Regulate Xylem Formation in Populus. FRONTIERS IN PLANT SCIENCE 2020; 11:586014. [PMID: 33193536 PMCID: PMC7652770 DOI: 10.3389/fpls.2020.586014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 09/29/2020] [Indexed: 05/05/2023]
Abstract
Brassinosteroid (BR) signaling has long been reported to have an effect on xylem development, but the detailed mechanism remains unclear, especially in tree species. In this study, we find PdC3H17, which was demonstrated to mediate xylem formation driven by auxin in our previous report, is also involved in BR-promoted xylem development. Y1H analysis, EMSA, and transcription activation assay confirmed that PdC3H17 was directly targeted by PdBES1, which is a key transcriptional regulator in BR signaling. Tissue specificity expression analysis and in situ assay revealed that PdC3H17 had an overlapping expression profile with PdBES1. Hormone treatment examinations verified that xylem phenotypes in PdC3H17 transgenic plants, which were readily apparent in normal condition, were attenuated by treatment with either brassinolide or the BR biosynthesis inhibitor propiconazole. The subsequent quantitative real-time polymerase chain reaction (qRT-PCR) analyses further revealed that BR converged with PdC3H17 to influence transcription of downstream xylem-related genes. Additionally, the enhancement of xylem differentiation by auxin in PdC3H17 overexpression plants was significantly attenuated compared with wild-type and dominant negative plants due to BR deficiency, which suggested that the BR- and auxin-responsive gene PdC3H17 acted as an mediation of these two hormones to facilitate xylem development. Taken together, our results demonstrate that BR signaling converges with auxin-mediated PdC3H17 to regulate xylem formation in Populus and thus provide insight into the regulation mechanism of BRs and the crosstalk with auxin signaling on xylem formation.
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Affiliation(s)
- Xianfeng Tang
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Shandong Institute of Energy Technology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Congpeng Wang
- College of Resources and Environment, Qingdao Agricultural University, Qingdao, China
| | - Yu Liu
- College of Resources and Environment, Qingdao Agricultural University, Qingdao, China
| | - Guo He
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Shandong Institute of Energy Technology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Nana Ma
- State Key Laboratory of Crop Biology, College of Life Science, Shandong Agricultural University, Tai’an, China
| | - Guohua Chai
- College of Resources and Environment, Qingdao Agricultural University, Qingdao, China
| | - Shengjun Li
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Shandong Institute of Energy Technology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Hua Xu
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Shandong Institute of Energy Technology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
- *Correspondence: Hua Xu,
| | - Gongke Zhou
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Shandong Institute of Energy Technology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
- College of Resources and Environment, Qingdao Agricultural University, Qingdao, China
- Gongke Zhou,
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43
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Cabello JV, Chan RL. Arabidopsis and sunflower plants with increased xylem area show enhanced seed yield. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 99:717-732. [PMID: 31009150 DOI: 10.1111/tpj.14356] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 04/09/2019] [Accepted: 04/17/2019] [Indexed: 06/09/2023]
Abstract
Plant architecture plasticity determines the efficiency at harvesting and plays a major role defining biomass and seed yield. We observed that several previously described transgenic genotypes exhibiting increased seed yield also show wider stems and more vascular bundles than wild-type plants. Here, the relationship between these characteristics and seed yield was investigated. Hanging weight on the main stem of Arabidopsis plants provoked significant stem widening. Such widening was accompanied by an increase in the number of vascular bundles and about 100% of yield increase. In parallel, lignin deposition diminished. Vascular bundle formation started in the upper internode and continued downstream. AUX/LAX carriers were essential for this response. The increase of vascular bundles was reverted 3 weeks after the treatment leading to an enlarged xylem area. Aux1, lax1, and lax3 mutant plants were also able to enlarge their stems after the treatment, whereas lax2 plants did not. However, none of these mutants exhibited more vascular bundles or seed yield compared with untreated plants. Weight-induced xylem area enhancement and increased seed yield were also observed in sunflower plants. Altogether these results showed a strong correlation between the number of vascular bundles and enhanced seed yield under a long-day photoperiod. Furthermore, changes in the levels of auxin carriers affected both these processes in the same manner, suggesting that there may be an underlying causality.
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Affiliation(s)
- Julieta V Cabello
- Instituto de Agrobiotecnología del Litoral, Universidad Nacional del Litoral, CONICET, Centro Científico Tecnológico CONICET Santa Fe, Colectora Ruta Nacional N° 168 km. 0, Paraje El Pozo, (3000), Santa Fe, Argentina
| | - Raquel L Chan
- Instituto de Agrobiotecnología del Litoral, Universidad Nacional del Litoral, CONICET, Centro Científico Tecnológico CONICET Santa Fe, Colectora Ruta Nacional N° 168 km. 0, Paraje El Pozo, (3000), Santa Fe, Argentina
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44
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Hearn DJ. Turing-like mechanism in a stochastic reaction-diffusion model recreates three dimensional vascular patterning of plant stems. PLoS One 2019; 14:e0219055. [PMID: 31339881 PMCID: PMC6715405 DOI: 10.1371/journal.pone.0219055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Accepted: 06/16/2019] [Indexed: 11/19/2022] Open
Abstract
Vascular tissue in plants provides a resource distribution network for water and nutrients that exhibits remarkable diversity in patterning among different species. In many succulent plants, the vascular network includes longitudinally-oriented supplemental vascular bundles (SVBs) in the central core of the succulent stems and roots in addition to the more typical zone of vascular tissue development (vascular cambium) in a cylinder at the periphery of the succulent organ. Plant SVBs evolved in over 38 plant families often in tandem with evolutionary increases in stem and root parenchyma storage tissue, so it is of interest to understand the evolutionary-developmental processes responsible for their recurrent evolution and patterning. Previous mathematical models have successfully recreated the two-dimensional vascular patterns in stem and root cross sections, but such models have yet to recreate three-dimensional vascular patterning. Here, a stochastic reaction-diffusion model of plant vascular bundle patterning is developed in an effort to highlight a potential mechanism of three dimensional patterning-Turing pattern formation coupled with longitudinal efflux of a regulatory molecule. A relatively simple model of four or five molecules recreated empirical SVB patterns and many other common vascular arrangements. SVBs failed to develop below a threshold width of parenchymatous tissues, suggesting a mechanism of evolutionary character loss due to changes in the spatial context in which development takes place. Altered diffusion rates of the modeled activator and substrate molecules affected the number and size of the simulated SVBs. This work provides a first mathematical model employing a stochastic Turing-type mechanism that recreates three dimensional vascular patterns seen in plant stems. The model offers predictions that can be tested using molecular-genetic approaches. Evolutionary-developmental ramifications concerning evolution of diffusion rates, organ size and geometry are discussed.
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Affiliation(s)
- David J. Hearn
- Department of Biological Sciences, Towson University, Towson, Maryland, United States of America
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45
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Roodt D, Li Z, Van de Peer Y, Mizrachi E. Loss of Wood Formation Genes in Monocot Genomes. Genome Biol Evol 2019; 11:1986-1996. [PMID: 31173081 PMCID: PMC6644875 DOI: 10.1093/gbe/evz115] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2019] [Indexed: 12/23/2022] Open
Abstract
Woodiness (secondary xylem derived from vascular cambium) has been gained and lost multiple times in the angiosperms, but has been lost ancestrally in all monocots. Here, we investigate the conservation of genes involved in xylogenesis in fully sequenced angiosperm genomes, hypothesizing that monocots have lost some essential orthologs involved in this process. We analyzed the conservation of genes preferentially expressed in the developing secondary xylem of two eudicot trees in the sequenced genomes of 26 eudicot and seven monocot species, and the early diverging angiosperm Amborella trichopoda. We also reconstructed a regulatory model of early vascular cambial cell identity and differentiation and investigated the conservation of orthologs across the angiosperms. Additionally, we analyzed the genome of the aquatic seagrass Zostera marina for additional losses of genes otherwise essential to, especially, secondary cell wall formation. Despite almost complete conservation of orthology within the early cambial differentiation gene network, we show a clear pattern of loss of genes preferentially expressed in secondary xylem in the monocots that are highly conserved across eudicot species. Our study provides candidate genes that may have led to the loss of vascular cambium in the monocots, and, by comparing terrestrial angiosperms to an aquatic monocot, highlights genes essential to vasculature on land.
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Affiliation(s)
- Danielle Roodt
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, South Africa
- Genomics Research Institute, University of Pretoria, South Africa
| | - Zhen Li
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Belgium
- VIB Center for Plant Systems Biology, VIB, Ghent, Belgium
- Bioinformatics Institute Ghent, Ghent University, Belgium
| | - Yves Van de Peer
- Genomics Research Institute, University of Pretoria, South Africa
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Belgium
- VIB Center for Plant Systems Biology, VIB, Ghent, Belgium
- Bioinformatics Institute Ghent, Ghent University, Belgium
- Department of Biochemistry, Genetics and Microbiology, Centre for Microbial Ecology and Genomics, University of Pretoria, South Africa
| | - Eshchar Mizrachi
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, South Africa
- Genomics Research Institute, University of Pretoria, South Africa
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Wang X, Zhang R, Shi Z, Zhang Y, Sun X, Ji Y, Zhao Y, Wang J, Zhang Y, Xing J, Wang Y, Wang R, Song W, Zhao J. Multi-omics analysis of the development and fracture resistance for maize internode. Sci Rep 2019; 9:8183. [PMID: 31160669 PMCID: PMC6547879 DOI: 10.1038/s41598-019-44690-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 05/21/2019] [Indexed: 12/26/2022] Open
Abstract
The maize stalk is an important mechanical supporting tissue. The stalk fracture resistance is closely related to lodging resistance, and thus the yield. In this study, we showed that the basal zone (BZ) was more fragile than the middle zone (MZ) of the stalk internode before tasseling. In order to clarify the relationship between the different zones and fragile resistance between the internodes, we systematically analyzed the phenotypic, metabolomic and transcriptomic differences. The results indicated that the BZ zone had lower stalk strength, which corresponded to the results of less lignin, cellulose and hemicellulose than that of the MZ. The 27 highly enriched metabolites and 4430 highly expressed genes in the BZ mainly participated in pentose phosphate, and in ribosome and sterol synthesis pathways, respectively. In addition, the BZ had higher vascular bundles density but smaller size compared with the MZ. By contrast, the 28 highly enriched known metabolites and 4438 highly expressed genes in the MZ were mainly involved in lignin synthesis, and secondary metabolites synthesis, respectively, especially the phenylpropanoid synthesis. The results provide a deeper understanding of the relationship between development and fracture differences in stalk, and may facilitate the improvement of field management practice to reduce lodging.
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Affiliation(s)
- Xiaqing Wang
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Ruyang Zhang
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Zi Shi
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Ying Zhang
- Beijing Key Lab of Digital Plant, Beijing Research Center for Information Technology in Agriculture, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 11, Beijing, 100097, China
| | - Xuan Sun
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Yulong Ji
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Yanxin Zhao
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Jidong Wang
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Yunxia Zhang
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Jinfeng Xing
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Yuandong Wang
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Ronghuan Wang
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China
| | - Wei Song
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China.
| | - Jiuran Zhao
- Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture and Forestry Sciences, Shuguang Huayuan Middle Road, Haidian District, No. 9, Beijing, 100097, China.
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Lee J, Han S, Lee HY, Jeong B, Heo TY, Hyun TK, Kim K, Je BI, Lee H, Shim D, Park SJ, Ryu H. Brassinosteroids facilitate xylem differentiation and wood formation in tomato. PLANTA 2019; 249:1391-1403. [PMID: 30673841 DOI: 10.1007/s00425-019-03094-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 01/14/2019] [Indexed: 06/09/2023]
Abstract
BR signaling pathways facilitate xylem differentiation and wood formation by fine tuning SlBZR1/SlBZR2-mediated gene expression networks involved in plant secondary growth. Brassinosteroid (BR) signaling and BR crosstalk with diverse signaling cues are involved in the pleiotropic regulation of plant growth and development. Recent studies reported the critical roles of BR biosynthesis and signaling in vascular bundle development and plant secondary growth; however, the molecular bases of these roles are unclear. Here, we performed comparative physiological and anatomical analyses of shoot morphological growth in a cultivated wild-type tomato (Solanum lycopersicum cv. BGA) and a BR biosynthetic mutant [Micro Tom (MT)]. We observed that the canonical BR signaling pathway was essential for xylem differentiation and sequential wood formation by facilitating plant secondary growth. The gradual retardation of xylem development phenotypes during shoot vegetative growth in the BR-deficient MT tomato mutant recovered completely in response to exogenous BR treatment or genetic complementation of the BR biosynthetic DWARF (D) gene. By contrast, overexpression of the tomato Glycogen synthase kinase 3 (SlGSK3) or CRISPR-Cas9 (CR)-mediated knockout of the tomato Brassinosteroid-insensitive 1 (SlBRI1) impaired BR signaling and resulted in severely defective xylem differentiation and secondary growth. Genetic modulation of the transcriptional activity of the tomato Brassinazole-resistant 1/2 (SlBZR1/SlBZR2) confirmed the positive roles of BR signaling pathways for xylem differentiation and secondary growth. Our data indicate that BR signaling pathways directly promote xylem differentiation and wood formation by canonical BR-activated SlBZR1/SlBZR2.
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Affiliation(s)
- Jinsu Lee
- Department of Biology, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Seahee Han
- National Agrobiodiversity Center, National Academy of Agricultural Science RDA, Jeonju, 54875, Republic of Korea
| | - Hwa-Yong Lee
- Department of Biology, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Bomi Jeong
- Department of Information and Statistics, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Tae-Young Heo
- Department of Information and Statistics, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Tae Kyung Hyun
- Department of Industrial Plant Science and Technology, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Kyunghwan Kim
- Department of Biology, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Byoung Il Je
- Department of Horticultural Bioscience, College of Natural Resource and Life Science, Pusan National University, Miryang, 50467, Republic of Korea
| | - Horim Lee
- Department of Biotechnology, Duksung Women's University, Seoul, 01369, Republic of Korea
| | - Donghwan Shim
- Department of Forest Bio-Resources, National Institute of Forest Science, Suwon, 16631, Republic of Korea
| | - Soon Ju Park
- Division of Biological Sciences, Research Institute for Basic Science, Wonkwang University, Iksan, 54538, Republic of Korea
| | - Hojin Ryu
- Department of Biology, Chungbuk National University, Cheongju, 28644, Republic of Korea.
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Planas-Riverola A, Gupta A, Betegón-Putze I, Bosch N, Ibañes M, Caño-Delgado AI. Brassinosteroid signaling in plant development and adaptation to stress. Development 2019; 146:146/5/dev151894. [PMID: 30872266 PMCID: PMC6432667 DOI: 10.1242/dev.151894] [Citation(s) in RCA: 215] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Brassinosteroids (BRs) are steroid hormones that are essential for plant growth and development. These hormones control the division, elongation and differentiation of various cell types throughout the entire plant life cycle. Our current understanding of the BR signaling pathway has mostly been obtained from studies using Arabidopsis thaliana as a model. In this context, the membrane steroid receptor BRI1 (BRASSINOSTEROID INSENSITIVE 1) binds directly to the BR ligand, triggering a signal cascade in the cytoplasm that leads to the transcription of BR-responsive genes that drive cellular growth. However, recent studies of the primary root have revealed distinct BR signaling pathways in different cell types and have highlighted cell-specific roles for BR signaling in controlling adaptation to stress. In this Review, we summarize our current knowledge of the spatiotemporal control of BR action in plant growth and development, focusing on BR functions in primary root development and growth, in stem cell self-renewal and death, and in plant adaption to environmental stress. Summary: This Review summarizes current knowledge of the spatiotemporal control of brassinosteroid function in plants, focusing on primary root development and growth, stem cell self-renewal and death, and adaptation to environmental stress.
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Affiliation(s)
- Ainoa Planas-Riverola
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Barcelona E-08193, Spain
| | - Aditi Gupta
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Barcelona E-08193, Spain
| | - Isabel Betegón-Putze
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Barcelona E-08193, Spain
| | - Nadja Bosch
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Barcelona E-08193, Spain
| | - Marta Ibañes
- Departament de Física de la Matèria Condensada, Universitat de Barcelona, Barcelona 08028, Spain.,Universitat de Barcelona Institute of Complex Systems (UBICS), Universitat de Barcelona, Barcelona 08028, Spain
| | - Ana I Caño-Delgado
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Barcelona E-08193, Spain
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Tikhomirova LI, Bazarnova NG, Sinitsyna AA. Histochemical Study of Xylem Cells in In Vitro Culture of Iris sibirica L. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2019. [DOI: 10.1134/s1068162018070129] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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50
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Exogenous Application of Phytohormones Promotes Growth and Regulates Expression of Wood Formation-Related Genes in Populus simonii × P. nigra. Int J Mol Sci 2019; 20:ijms20030792. [PMID: 30759868 PMCID: PMC6387376 DOI: 10.3390/ijms20030792] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 02/06/2019] [Accepted: 02/11/2019] [Indexed: 02/06/2023] Open
Abstract
Although phytohormones are known to be important signal molecules involved in wood formation, their roles are still largely unclear. Here, Populus simonii × P. nigra seedlings were treated with different concentrations of exogenous phytohormones, indole-3-acetic acid (IAA), gibberellin (GA3), and brassinosteroid (BR), and the effects of phytohormones on growth were investigated. Next, 27 genes with known roles in wood formation were selected for qPCR analysis to determine tissue-specificity and timing of responses to phytohormone treatments. Compared to the control, most IAA, GA3, and BR concentrations significantly increased seedling height. Meanwhile, IAA induced significant seedling stem diameter and cellulose content increases that peaked at 3 and 30 mg·L−1, respectively. Significant increase in cellulose content was also observed in seedlings treated with 100 mg·L−1 GA3. Neither stem diameter nor cellulose content of seedlings were affected by BR treatment significantly, although slight effects were observed. Anatomical measurements demonstrated improved xylem, but not phloem, development in IAA- and BR-treated seedlings. Most gene expression patterns induced by IAA, GA3, and BR differed among tissues. Many IAA response genes were also regulated by GA3, while BR-induced transcription was weaker and slower in Populus than for IAA and GA3. These results reveal the roles played by phytohormones in plant growth and lay the foundation for exploring molecular regulatory mechanisms of wood formation in Populus.
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