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Deng J, Ahmad B, Deng X, Fan Z, Liu L, Lu X, Pan Y, Zha X. Genome-wide analysis of the mulberry ( Morus abla L.) GH9 gene family and the functional characterization of MaGH9B6 during the development of the abscission zone. FRONTIERS IN PLANT SCIENCE 2024; 15:1352635. [PMID: 38633459 PMCID: PMC11021789 DOI: 10.3389/fpls.2024.1352635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 03/18/2024] [Indexed: 04/19/2024]
Abstract
Plant glycoside hydrolase family 9 genes (GH9s) are widely distributed in plants and involved in a variety of cellular and physiological processes. In the current study, nine GH9 genes were identified in the mulberry and were divided into two subfamilies based on the phylogenetic analysis. Conserved motifs and gene structure analysis suggested that the evolution of the two subfamilies is relatively conserved and the glycoside hydrolase domain almost occupy the entire coding region of the GH9s gene. Only segmental duplication has played a role in the expansion of gene family. Collinearity analysis showed that mulberry GH9s had the closest relationship with poplar GH9s. MaGH9B1, MaGH9B6, MaGH9B5, and MaGH9B3 were detected to have transcript accumulation in the stalk of easy-to drop mature fruit drop, suggesting that these could play a role in mulberry fruit drop. Multiple cis-acting elements related to plant hormones and abiotic stress responses were found in the mulberry GH9 promoter regions and showed different activities under exogenous abscisic acid (ABA) and 2,4- dichlorophenoxyacetic acid (2,4-D) stresses. We found that the lignin content in the fruit stalk decreased with the formation of the abscission zone (AZ), which could indirectly reflect the formation process of the AZ. These results provide a theoretical basis for further research on the role of GH9s in mulberry abscission.
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Affiliation(s)
- Jing Deng
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
| | - Bilal Ahmad
- National Key Laboratory of Tropical Crop Breeding, Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Xuan Deng
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
| | - Zelin Fan
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
| | - Lianlian Liu
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
| | - Xiuping Lu
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
| | - Yu Pan
- College of Horticulture and Landscape Architecture, Southwest University, Chongqing, China
| | - Xingfu Zha
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
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Shu H, Sun S, Wang X, Chen J, Yang C, Zhang G, Han H, Li Z, Liang T, Liu R. Thidiazuron combined with cyclanilide modulates hormone pathways and ROS systems in cotton, increasing defoliation at low temperatures. FRONTIERS IN PLANT SCIENCE 2024; 15:1333816. [PMID: 38633458 PMCID: PMC11021790 DOI: 10.3389/fpls.2024.1333816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 03/21/2024] [Indexed: 04/19/2024]
Abstract
Low temperatures decrease the thidiazuron (TDZ) defoliation efficiency in cotton, while cyclanilide (CYC) combined with TDZ can improve the defoliation efficiency at low temperatures, but the mechanism is unknown. This study analyzed the effect of exogenous TDZ and CYC application on cotton leaf abscissions at low temperatures (daily mean temperature: 15°C) using physiology and transcriptomic analysis. The results showed that compared with the TDZ treatment, TDZ combined with CYC accelerated cotton leaf abscission and increased the defoliation rate at low temperatures. The differentially expressed genes (DEGs) in cotton abscission zones (AZs) were subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to compare the enriched GO terms and KEGG pathways between the TDZ treatment and TDZ combined with CYC treatment. TDZ combined with CYC could induce more DEGs in cotton leaf AZs at low temperatures, and these DEGs were related to plant hormone and reactive oxygen species (ROS) pathways. CYC is an auxin transport inhibitor. TDZ combined with CYC not only downregulated more auxin response related genes but also upregulated more ethylene and jasmonic acid (JA) response related genes at low temperatures, and it decreased the indole-3-acetic acid (IAA) content and increased the JA and 1-aminocyclopropane-1-carboxylic acid (ACC) contents, which enhanced cotton defoliation. In addition, compared with the TDZ treatment alone, TDZ combined with CYC upregulated the expression of respiratory burst oxidase homologs (RBOH) genes and the hydrogen peroxide content in cotton AZs at low temperatures, which accelerated cotton defoliation. These results indicated that CYC enhanced the TDZ defoliation efficiency in cotton by adjusting hormone synthesis and response related pathways (including auxin, ethylene, and JA) and ROS production at low temperatures.
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Affiliation(s)
- Hongmei Shu
- Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences/Key Laboratory of Cotton and Rapeseed, Ministry of Agriculture and Rural Affairs, Nanjing, China
| | - Shangwen Sun
- Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences/Key Laboratory of Cotton and Rapeseed, Ministry of Agriculture and Rural Affairs, Nanjing, China
| | - Xiaojing Wang
- Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences/Key Laboratory of Cotton and Rapeseed, Ministry of Agriculture and Rural Affairs, Nanjing, China
| | - Jian Chen
- Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Changqin Yang
- Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences/Key Laboratory of Cotton and Rapeseed, Ministry of Agriculture and Rural Affairs, Nanjing, China
| | - Guowei Zhang
- Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences/Key Laboratory of Cotton and Rapeseed, Ministry of Agriculture and Rural Affairs, Nanjing, China
| | - Huanyong Han
- Cotton Research Institute, Xinjiang Academy of Agricultural and Reclamation Science, Shihezi, China
| | - Zhikang Li
- Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences/Key Laboratory of Cotton and Rapeseed, Ministry of Agriculture and Rural Affairs, Nanjing, China
| | - Ting Liang
- Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences/Key Laboratory of Cotton and Rapeseed, Ministry of Agriculture and Rural Affairs, Nanjing, China
| | - Ruixian Liu
- Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences/Key Laboratory of Cotton and Rapeseed, Ministry of Agriculture and Rural Affairs, Nanjing, China
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Safran J, Tabi W, Ung V, Lemaire A, Habrylo O, Bouckaert J, Rouffle M, Voxeur A, Pongrac P, Bassard S, Molinié R, Fontaine JX, Pilard S, Pau-Roblot C, Bonnin E, Larsen DS, Morel-Rouhier M, Girardet JM, Lefebvre V, Sénéchal F, Mercadante D, Pelloux J. Plant polygalacturonase structures specify enzyme dynamics and processivities to fine-tune cell wall pectins. THE PLANT CELL 2023; 35:3073-3091. [PMID: 37202370 PMCID: PMC10396364 DOI: 10.1093/plcell/koad134] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 04/11/2023] [Accepted: 05/10/2023] [Indexed: 05/20/2023]
Abstract
Polygalacturonases (PGs) fine-tune pectins to modulate cell wall chemistry and mechanics, impacting plant development. The large number of PGs encoded in plant genomes leads to questions on the diversity and specificity of distinct isozymes. Herein, we report the crystal structures of 2 Arabidopsis thaliana PGs, POLYGALACTURONASE LATERAL ROOT (PGLR), and ARABIDOPSIS DEHISCENCE ZONE POLYGALACTURONASE2 (ADPG2), which are coexpressed during root development. We first determined the amino acid variations and steric clashes that explain the absence of inhibition of the plant PGs by endogenous PG-inhibiting proteins (PGIPs). Although their beta helix folds are highly similar, PGLR and ADPG2 subsites in the substrate binding groove are occupied by divergent amino acids. By combining molecular dynamic simulations, analysis of enzyme kinetics, and hydrolysis products, we showed that these structural differences translated into distinct enzyme-substrate dynamics and enzyme processivities: ADPG2 showed greater substrate fluctuations with hydrolysis products, oligogalacturonides (OGs), with a degree of polymerization (DP) of ≤4, while the DP of OGs generated by PGLR was between 5 and 9. Using the Arabidopsis root as a developmental model, exogenous application of purified enzymes showed that the highly processive ADPG2 had major effects on both root cell elongation and cell adhesion. This work highlights the importance of PG processivity on pectin degradation regulating plant development.
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Affiliation(s)
- Josip Safran
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Wafae Tabi
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Vanessa Ung
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Adrien Lemaire
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Olivier Habrylo
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Julie Bouckaert
- UMR 8576 Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), 50 Avenue de Halley, Villeneuve d’Ascq 59658, France
| | - Maxime Rouffle
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Aline Voxeur
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), Versailles 78000, France
| | - Paula Pongrac
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Solène Bassard
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Roland Molinié
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Jean-Xavier Fontaine
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Serge Pilard
- Plateforme Analytique, Université de Picardie, 33, Rue St Leu, Amiens 80039, France
| | - Corinne Pau-Roblot
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Estelle Bonnin
- INRAE, UR 1268 Biopolymers, Interactions Assemblies, CS 71627, Nantes Cedex 3 44316, France
| | - Danaé Sonja Larsen
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | | | | | - Valérie Lefebvre
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Fabien Sénéchal
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Davide Mercadante
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Jérôme Pelloux
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
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Sertse D, You FM, Klymiuk V, Haile JK, N'Diaye A, Pozniak CJ, Cloutier S, Kagale S. Historical Selection, Adaptation Signatures, and Ambiguity of Introgressions in Wheat. Int J Mol Sci 2023; 24:ijms24098390. [PMID: 37176097 PMCID: PMC10179502 DOI: 10.3390/ijms24098390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 05/03/2023] [Accepted: 05/04/2023] [Indexed: 05/15/2023] Open
Abstract
Wheat was one of the crops domesticated in the Fertile Crescent region approximately 10,000 years ago. Despite undergoing recent polyploidization, hull-to-free-thresh transition events, and domestication bottlenecks, wheat is now grown in over 130 countries and accounts for a quarter of the world's cereal production. The main reason for its widespread success is its broad genetic diversity that allows it to thrive in different environments. To trace historical selection and hybridization signatures, genome scans were performed on two datasets: approximately 113K SNPs from 921 predominantly bread wheat accessions and approximately 110K SNPs from about 400 wheat accessions representing all ploidy levels. To identify environmental factors associated with the loci, a genome-environment association (GEA) was also performed. The genome scans on both datasets identified a highly differentiated region on chromosome 4A where accessions in the first dataset were dichotomized into a group (n = 691), comprising nearly all cultivars, wild emmer, and most landraces, and a second group (n = 230), dominated by landraces and spelt accessions. The grouping of cultivars is likely linked to their potential ancestor, bread wheat cv. Norin-10. The 4A region harbored important genes involved in adaptations to environmental conditions. The GEA detected loci associated with latitude and temperature. The genetic signatures detected in this study provide insight into the historical selection and hybridization events in the wheat genome that shaped its current genetic structure and facilitated its success in a wide spectrum of environmental conditions. The genome scans and GEA approaches applied in this study can help in screening the germplasm housed in gene banks for breeding, and for conservation purposes.
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Affiliation(s)
- Demissew Sertse
- Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, SK S7N 0W9, Canada
| | - Frank M You
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6, Canada
| | - Valentyna Klymiuk
- Crop Development Centre, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada
| | - Jemanesh K Haile
- Crop Development Centre, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada
| | - Amidou N'Diaye
- Crop Development Centre, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada
| | - Curtis J Pozniak
- Crop Development Centre, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada
| | - Sylvie Cloutier
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6, Canada
| | - Sateesh Kagale
- Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, SK S7N 0W9, Canada
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Yu Y, Beyene G, Villmer J, Duncan KE, Hu H, Johnson T, Doust AN, Taylor NJ, Kellogg EA. Grain shattering by cell death and fracture in Eragrostis tef. PLANT PHYSIOLOGY 2023; 192:222-239. [PMID: 36756804 PMCID: PMC10152664 DOI: 10.1093/plphys/kiad079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 12/15/2022] [Accepted: 01/11/2023] [Indexed: 05/03/2023]
Abstract
Abscission, known as shattering in crop species, is a highly regulated process by which plants shed parts. Although shattering has been studied extensively in cereals and a number of regulatory genes have been identified, much diversity in the process remains to be discovered. Teff (Eragrostis tef) is a crop native to Ethiopia that is potentially highly valuable worldwide for its nutritious grain and drought tolerance. Previous work has suggested that grain shattering in Eragrostis might have little in common with other cereals. In this study, we characterize the anatomy, cellular structure, and gene regulatory control of the abscission zone (AZ) in E. tef. We show that the AZ of E. tef is a narrow stalk below the caryopsis, which is common in Eragrostis species. X-ray microscopy, scanning electron microscopy, transmission electron microscopy, and immunolocalization of cell wall components showed that the AZ cells are thin walled and break open along with programmed cell death (PCD) at seed maturity, rather than separating between cells as in other studied species. Knockout of YABBY2/SHATTERING1, documented to control abscission in several cereals, had no effect on abscission or AZ structure in E. tef. RNA sequencing analysis showed that genes related to PCD and cell wall modification are enriched in the AZ at the early seed maturity stage. These data show that E. tef drops its seeds using a unique mechanism. Our results provide the groundwork for understanding grain shattering in Eragrostis and further improvement of shattering in E. tef.
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Affiliation(s)
- Yunqing Yu
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA
| | - Getu Beyene
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA
| | - Justin Villmer
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA
| | - Keith E Duncan
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA
| | - Hao Hu
- Department of Plant Biology, Ecology, and Evolution, Oklahoma State University, Stillwater, OK 74078, USA
| | - Toni Johnson
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA
| | - Andrew N Doust
- Department of Plant Biology, Ecology, and Evolution, Oklahoma State University, Stillwater, OK 74078, USA
| | - Nigel J Taylor
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA
| | - Elizabeth A Kellogg
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA
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Low Temperature Inhibits the Defoliation Efficiency of Thidiazuron in Cotton by Regulating Plant Hormone Synthesis and the Signaling Pathway. Int J Mol Sci 2022; 23:ijms232214208. [PMID: 36430686 PMCID: PMC9694417 DOI: 10.3390/ijms232214208] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 11/03/2022] [Accepted: 11/15/2022] [Indexed: 11/19/2022] Open
Abstract
Thidiazuron (TDZ) is the main defoliant used in production to promote leaf abscission for machine-picked cotton. Under low temperatures, the defoliation rate of cotton treated with TDZ decreases and the time of defoliation is delayed, but there is little information about this mechanism. In this study, RNA-seq and physiological analysis are performed to reveal the transcriptome profiling and change in endogenous phytohormones upon TDZ treatment in abscission zones (AZs) under different temperatures (daily mean temperatures: 25 °C and 15 °C). Genes differentially expressed in AZs between TDZ treatment and control under different temperatures were subjected to gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to compare the enriched GO terms and KEGG pathways between the two temperature conditions. The results show that, compared with the corresponding control group, TDZ induces many differentially expressed genes (DEGs) in AZs, and the results of the GO and KEGG analyses show that the plant hormone signaling transduction pathway is significantly regulated by TDZ. However, under low temperature, TDZ induced less DEGs, and the enriched GO terms and KEGG pathways were different with those under normal temperature condition. Many genes in the plant hormone signal transduction pathway could not be induced by TDZ under low temperature conditions. In particular, the upregulated ethylene-signaling genes and downregulated auxin-signaling genes in AZs treated with TDZ were significantly affected by low temperatures. Furthermore, the expression of ethylene and auxin synthesis genes and their content in AZs treated with TDZ were also regulated by low temperature conditions. The upregulated cell wall hydrolase genes induced by TDZ were inhibited by low temperatures. However, the inhibition of low temperature on genes in AZs treated with TDZ was relieved with the extension of the treatment time. Together, these results indicate that the responses of ethylene and auxin synthesis and the signaling pathway to TDZ are inhibited by low temperatures, which could not induce the expression of cell wall hydrolase genes, and then inhibit the separation of AZ cells and the abscission of cotton leaves. This result provides new insights into the mechanism of defoliation induced by TDZ under low temperature conditions.
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Integrated Transcriptome and Targeted Metabolite Analysis Reveal miRNA-mRNA Networks in Low-Light-Induced Lotus Flower Bud Abortion. Int J Mol Sci 2022; 23:ijms23179925. [PMID: 36077323 PMCID: PMC9456346 DOI: 10.3390/ijms23179925] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/21/2022] [Accepted: 08/23/2022] [Indexed: 11/16/2022] Open
Abstract
Most Nelumbo nucifera (lotus) flower buds were aborted during the growing season, notably in low-light environments. How lotus produces so many aborted flower buds is largely unknown. An integrated transcriptome and targeted metabolite analysis was performed to reveal the genetic regulatory networks underlying lotus flower bud abortion. A total of 233 miRNAs and 25,351 genes were identified in lotus flower buds, including 68 novel miRNAs and 1108 novel genes. Further enrichment analysis indicated that sugar signaling plays a potential central role in regulating lotus flower bud abortion. Targeted metabolite analysis showed that trehalose levels declined the most in the aborting flower buds. A potential regulatory network centered on miR156 governs lotus flower bud abortion, involving multiple miRNA-mRNA pairs related to cell integrity, cell proliferation and expansion, and DNA repair. Genetic analysis showed that miRNA156-5p-overexpressing lotus showed aggravated flower bud abortion phenotypes. Trehalose-6-P synthase 1 (TPS1), which is required for trehalose synthase, had a negative regulatory effect on miR156 expression. TPS1-overexpression lotus showed significantly decreased flower bud abortion rates both in normal-light and low-light environments. Our study establishes a possible genetic basis for how lotus produces so many aborted flower buds, facilitating genetic improvement of lotus’ shade tolerance.
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Cabrales-Orona G, Martínez-Gallardo N, Délano-Frier JP. Functional Characterization of an Amaranth Natterin-4-Like-1 Gene in Arabidopsis thaliana. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2022. [DOI: 10.3389/fsufs.2021.814188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The functional characterization of an Amaranthus hypochondriacus Natterin-4-Like-1 gene (AhN4L-1) coding for an unknown function protein characterized by the presence of an aerolysin-like pore-forming domain in addition to two amaranthin-like agglutinin domains is herewith described. Natterin and nattering-like proteins have been amply described in the animal kingdom. However, the role of nattering-like proteins in plants is practically unknown. The results described in this study, obtained from gene expression data in grain amaranth and from AhN4L-1-overexpressing Arabidopsis thaliana plants indicated that this gene was strongly induced by several biotic and abiotic conditions in grain amaranth, whereas data obtained from the overexpressing Arabidopsis plants further supported the defensive function of this gene, mostly against bacterial and fungal plant pathogens. GUS and GFP AhN4L-1 localization in roots tips, leaf stomata, stamens and pistils also suggested a defensive function in these organs, although its participation in flowering processes, such as self-incompatibility and abscission, is also possible. However, contrary to expectations, the overexpression of this gene negatively affected the vegetative and reproductive growth of the transgenic plants, which also showed no increased tolerance to salinity and water-deficit stress. The latter despite the maintenance of significantly higher chlorophyll levels and photosynthetic parameters under intense salinity stress. These results are discussed in the context of the physiological roles known to be played by related lectins and AB proteins in plants.
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9
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Morcillo F, Serret J, Beckers A, Collin M, Tisné S, George S, Poveda R, Louise C, Tranbarger TJ. A Non-Shedding Fruit Elaeis oleifera Palm Reveals Perturbations to Hormone Signaling, ROS Homeostasis, and Hemicellulose Metabolism. Genes (Basel) 2021; 12:1724. [PMID: 34828330 PMCID: PMC8621672 DOI: 10.3390/genes12111724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/22/2021] [Accepted: 10/26/2021] [Indexed: 11/16/2022] Open
Abstract
The developmentally programmed loss of a plant organ is called abscission. This process is characterized by the ultimate separation of adjacent cells in the abscission zone (AZ). The discovery of an American oil palm (Elaeis oleifera) variant that does not shed its has allowed for the study of the mechanisms of ripe fruit abscission in this species. A comparative transcriptome analysis was performed to compare the fruit AZs of the non-shedding E. oleifera variant to an individual of the same progeny that sheds its ripe fruit normally. The study provides evidence for widespread perturbation to gene expression in the AZ of the non-shedding variant, compared to the normal fruit-shedding control, and offers insight into abscission-related functions. Beyond the genes with known or suspected roles during organ abscission or indehiscence that were identified, a list of genes with hormone-related functions, including ethylene, jasmonic acid, abscisic acid, cytokinin and salicylic acid, in addition to reactive oxygen species (ROS) metabolism, transcriptional responses and signaling pathways, was compiled. The results also allowed a comparison between the ripe fruit abscission processes of the African and American oil palm species at the molecular level and revealed commonalities with environmental stress pathways.
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Affiliation(s)
- Fabienne Morcillo
- DIADE (Diversité, Adaptation, Développement des Plantes), University of Montpellier, CIRAD (Centre de Coopération Internationale en Recherche Agronomique pour le Développement), IRD (Institut de Recherche pour le Développement), 34393 Montpellier, France; (F.M.); (J.S.); (A.B.); (M.C.)
- CIRAD, UMR (Unité Mixte de Recherche) DIADE, 34398 Montpellier, France
| | - Julien Serret
- DIADE (Diversité, Adaptation, Développement des Plantes), University of Montpellier, CIRAD (Centre de Coopération Internationale en Recherche Agronomique pour le Développement), IRD (Institut de Recherche pour le Développement), 34393 Montpellier, France; (F.M.); (J.S.); (A.B.); (M.C.)
| | - Antoine Beckers
- DIADE (Diversité, Adaptation, Développement des Plantes), University of Montpellier, CIRAD (Centre de Coopération Internationale en Recherche Agronomique pour le Développement), IRD (Institut de Recherche pour le Développement), 34393 Montpellier, France; (F.M.); (J.S.); (A.B.); (M.C.)
| | - Myriam Collin
- DIADE (Diversité, Adaptation, Développement des Plantes), University of Montpellier, CIRAD (Centre de Coopération Internationale en Recherche Agronomique pour le Développement), IRD (Institut de Recherche pour le Développement), 34393 Montpellier, France; (F.M.); (J.S.); (A.B.); (M.C.)
| | - Sebastien Tisné
- CIRAD, UMR AGAP (Amélioration Génétique et Adaptation des Plantes Méditerranéennes et Tropicales), 34398 Montpellier, France;
- AGAP, University of Montpellier, CIRAD, INRAE (Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement), Institut Agro, 34398 Montpellier, France
| | - Simon George
- MGX-Montpellier GenomiX, University of Montpellier, CNRS (Centre National de la Recherche Scientifique), INSERM (Institut National de la Santé et de la Recherche Médicale), 34094 Montpellier, France;
| | - Roberto Poveda
- DANEC, Sangolqui/Rumiñahui, Sangolquí, Pichincha 171102, Ecuador;
| | | | - Timothy John Tranbarger
- DIADE (Diversité, Adaptation, Développement des Plantes), University of Montpellier, CIRAD (Centre de Coopération Internationale en Recherche Agronomique pour le Développement), IRD (Institut de Recherche pour le Développement), 34393 Montpellier, France; (F.M.); (J.S.); (A.B.); (M.C.)
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10
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Fooyontphanich K, Morcillo F, Joët T, Dussert S, Serret J, Collin M, Amblard P, Tangphatsornruang S, Roongsattham P, Jantasuriyarat C, Verdeil JL, Tranbarger TJ. Multi-scale comparative transcriptome analysis reveals key genes and metabolic reprogramming processes associated with oil palm fruit abscission. BMC PLANT BIOLOGY 2021; 21:92. [PMID: 33573592 PMCID: PMC7879690 DOI: 10.1186/s12870-021-02874-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/01/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Fruit abscission depends on cell separation that occurs within specialized cell layers that constitute an abscission zone (AZ). To determine the mechanisms of fleshy fruit abscission of the monocot oil palm (Elaeis guineensis Jacq.) compared with other abscission systems, we performed multi-scale comparative transcriptome analyses on fruit targeting the developing primary AZ and adjacent tissues. RESULTS Combining between-tissue developmental comparisons with exogenous ethylene treatments, and naturally occurring abscission in the field, RNAseq analysis revealed a robust core set of 168 genes with differentially regulated expression, spatially associated with the ripe fruit AZ, and temporally restricted to the abscission timing. The expression of a set of candidate genes was validated by qRT-PCR in the fruit AZ of a natural oil palm variant with blocked fruit abscission, which provides evidence for their functions during abscission. Our results substantiate the conservation of gene function between dicot dry fruit dehiscence and monocot fleshy fruit abscission. The study also revealed major metabolic transitions occur in the AZ during abscission, including key senescence marker genes and transcriptional regulators, in addition to genes involved in nutrient recycling and reallocation, alternative routes for energy supply and adaptation to oxidative stress. CONCLUSIONS The study provides the first reference transcriptome of a monocot fleshy fruit abscission zone and provides insight into the mechanisms underlying abscission by identifying key genes with functional roles and processes, including metabolic transitions, cell wall modifications, signalling, stress adaptations and transcriptional regulation, that occur during ripe fruit abscission of the monocot oil palm. The transcriptome data comprises an original reference and resource useful towards understanding the evolutionary basis of this fundamental plant process.
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Affiliation(s)
- Kim Fooyontphanich
- UMR DIADE, Institut de Recherche Pour le Développement, Université de Montpellier, IRD Centre de Montpellier, 911 Avenue Agropolis BP 64501, 34394 Cedex 5, Montpellier, France
- Grow A Green Co, Ltd. 556 Maha Chakraphat Rd. Namaung, Chachoengsao, Chachoengsao Province, 24000, Thailand
| | - Fabienne Morcillo
- UMR DIADE, Institut de Recherche Pour le Développement, Université de Montpellier, IRD Centre de Montpellier, 911 Avenue Agropolis BP 64501, 34394 Cedex 5, Montpellier, France
- CIRAD, DIADE, F-34398, Montpellier, France
| | - Thierry Joët
- UMR DIADE, Institut de Recherche Pour le Développement, Université de Montpellier, IRD Centre de Montpellier, 911 Avenue Agropolis BP 64501, 34394 Cedex 5, Montpellier, France
| | - Stéphane Dussert
- UMR DIADE, Institut de Recherche Pour le Développement, Université de Montpellier, IRD Centre de Montpellier, 911 Avenue Agropolis BP 64501, 34394 Cedex 5, Montpellier, France
| | - Julien Serret
- UMR DIADE, Institut de Recherche Pour le Développement, Université de Montpellier, IRD Centre de Montpellier, 911 Avenue Agropolis BP 64501, 34394 Cedex 5, Montpellier, France
| | - Myriam Collin
- UMR DIADE, Institut de Recherche Pour le Développement, Université de Montpellier, IRD Centre de Montpellier, 911 Avenue Agropolis BP 64501, 34394 Cedex 5, Montpellier, France
| | | | - Sithichoke Tangphatsornruang
- National Science and Technology Development Agency, 111 Thailand Science Park, Phahonyothin Road, Pathum Thani, Thailand
| | - Peerapat Roongsattham
- UMR DIADE, Institut de Recherche Pour le Développement, Université de Montpellier, IRD Centre de Montpellier, 911 Avenue Agropolis BP 64501, 34394 Cedex 5, Montpellier, France
- Department of Genetics, Faculty of Science, Kasetsart University Bangkhen Campus, 50 Phahonyothin Road Jatujak, Bangkok, Thailand
| | - Chatchawan Jantasuriyarat
- Department of Genetics, Faculty of Science, Kasetsart University Bangkhen Campus, 50 Phahonyothin Road Jatujak, Bangkok, Thailand
| | - Jean-Luc Verdeil
- CIRAD, UMR AGAP, F-34398, Montpellier, France
- AGAP, Univ Montpellier, CIRAD, INRAE, Institut Agro, Montpellier, France
| | - Timothy J Tranbarger
- UMR DIADE, Institut de Recherche Pour le Développement, Université de Montpellier, IRD Centre de Montpellier, 911 Avenue Agropolis BP 64501, 34394 Cedex 5, Montpellier, France.
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11
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López-Hernández F, Cortés AJ. Last-Generation Genome-Environment Associations Reveal the Genetic Basis of Heat Tolerance in Common Bean ( Phaseolus vulgaris L.). Front Genet 2019; 10:954. [PMID: 31824551 PMCID: PMC6883007 DOI: 10.3389/fgene.2019.00954] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 09/06/2019] [Indexed: 01/10/2023] Open
Abstract
Genome-environment associations (GEAs) are a powerful strategy for the study of adaptive traits in wild plant populations, yet they still lack behind in the use of modern statistical methods as the ones suggested for genome-wide association studies (GWASs). In order to bridge this gap, we couple GEA with last-generation GWAS algorithms in common bean to identify novel sources of heat tolerance across naturally heterogeneous ecosystems. Common bean (Phaseolus vulgaris L.) is the most important legume for human consumption, and breeding it for resistance to heat stress is key because annual increases in atmospheric temperature are causing decreases in yield of up to 9% for every 1°C. A total of 78 geo-referenced wild accessions, spanning the two gene pools of common bean, were genotyped by sequencing (GBS), leading to the discovery of 23,373 single-nucleotide polymorphism (SNP) markers. Three indices of heat stress were developed for each accession and inputted in last-generation algorithms (i.e. SUPER, FarmCPU, and BLINK) to identify putative associated loci with the environmental heterogeneity in heat stress. Best-fit models revealed 120 significantly associated alleles distributed in all 11 common bean chromosomes. Flanking candidate genes were identified using 1-kb genomic windows centered in each associated SNP marker. Some of these genes were directly linked to heat-responsive pathways, such as the activation of heat shock proteins (MED23, MED25, HSFB1, HSP40, and HSP20). We also found protein domains related to thermostability in plants such as S1 and Zinc finger A20 and AN1. Other genes were related to biological processes that may correlate with plant tolerance to high temperature, such as time to flowering (MED25, MBD9, and PAP), germination and seedling development (Pkinase_Tyr, Ankyrin-B, and Family Glicosil-hydrolase), cell wall stability (GAE6), and signaling pathway of abiotic stress via abscisic acid (histone-like transcription factors NFYB and phospholipase C) and auxin (Auxin response factor and AUX_IAA). This work offers putative associated loci for marker-assisted and genomic selection for heat tolerance in common bean. It also demonstrates that it is feasible to identify genome-wide environmental associations with modest sample sizes by using a combination of various carefully chosen environmental indices and last-generation GWAS algorithms.
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Affiliation(s)
- Felipe López-Hernández
- Corporación Colombiana de Investigación Agropecuaria (Agrosavia) - CI La Selva, Rionegro, Colombia
- Facultad de Ciencias – Grupo de Investigación en Sistemática Molecular, Universidad Nacional de Colombia - Sede Medellín, Medellín, Colombia
| | - Andrés J. Cortés
- Corporación Colombiana de Investigación Agropecuaria (Agrosavia) - CI La Selva, Rionegro, Colombia
- Facultad de Ciencias Agrarias - Departamento de Ciencias Forestales, Universidad Nacional de Colombia - Sede Medellín, Medellín, Colombia
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12
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Li C, Ma X, Huang X, Wang H, Wu H, Zhao M, Li J. Involvement of HD-ZIP I transcription factors LcHB2 and LcHB3 in fruitlet abscission by promoting transcription of genes related to the biosynthesis of ethylene and ABA in litchi. TREE PHYSIOLOGY 2019; 39:1600-1613. [PMID: 31222320 DOI: 10.1093/treephys/tpz071] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 05/07/2019] [Accepted: 06/11/2019] [Indexed: 05/28/2023]
Abstract
Abnormal fruitlet abscission is a limiting factor in the production of litchi, an economically important fruit in Southern Asia. Both ethylene and abscisic acid (ABA) induce organ abscission in plants. Although ACS/ACO and NCED genes are known to encode key enzymes required for ethylene and ABA biosynthesis, respectively, the transcriptional regulation of these genes is unclear in the process of plant organ shedding. Here, two polygalacturonase (PG) genes (LcPG1 and LcPG2) and two novel homeodomain-leucine zipper I transcription factors genes (LcHB2 and LcHB3) were identified as key genes associated with the fruitlet abscission in litchi. The expression of LcPG1 and LcPG2 was strongly associated with litchi fruitlet abscission, consistent with enhanced PG activity and reduced homogalacturonan content in fruitlet abscission zones (FAZs). The promoter activities of LcPG1/2 were enhanced by ethephon and ABA. In addition, the production of ethylene and ABA in fruitlets was significantly increased during fruit abscission. Consistently, expression of five genes (LcACO2, LcACO3, LcACS1, LcACS4 and LcACS7) related to ethylene biosynthesis and one gene (LcNCED3) related to ABA biosynthesis in FAZs were activated. Further, electrophoretic mobility shift assays and transient expression experiments demonstrated that both LcHB2 and LcHB3 could directly bind to the promoter of LcACO2/3, LcACS1/4/7 and LcNCED3 genes and activate their expression. Collectively, we propose that LcHB2/3 are involved in the litchi fruitlet abscission through positive regulation of ethylene and ABA biosynthesis.
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Affiliation(s)
- Caiqin Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Xingshuai Ma
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Xuming Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Huicong Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Hong Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China
| | - Minglei Zhao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Jianguo Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China
- Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China
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13
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Ge T, Huang X, Pan X, Zhang J, Xie R. Genome-wide identification and expression analysis of citrus fruitlet abscission-related polygalacturonase genes. 3 Biotech 2019; 9:250. [PMID: 31218174 DOI: 10.1007/s13205-019-1782-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 05/27/2019] [Indexed: 12/16/2022] Open
Abstract
Polygalacturonases (PGs) encoded by a relatively large gene family are involved in plant organ abscission, but few data is available in citrus. Here, to explore the role of PGs in citrus fruitlet abscission (CFA), we have obtained 38 citrus PG (CitPG) members, based on the citrus genome sequences. The ORF length varied from 378 to 2418 bp, encoding proteins with theoretical pI and molecular mass ranging from 4.83 to 9.92 and from 13,951.71 to 85,542.28, respectively. Most CitPGs contained no less than 3 introns, suggesting a high probability of alternative splicing. Phylogenetic tree revealed that all PGs could be divided into three groups, in which 9 CitPGs, including CitPG2, CitPG3, CitPG10, CitPG24, CitPG27, CitPG29, CitPG30, CitPG33 and CitPG34 possessed a close relationship with abscission-associated PGs, indicating their role in CFA. Expression analysis further demonstrated that CitPG2, CitPG29 and CitPG34 might be involved in CFA, the expression levels of which could be induced by ethylene, inhibited by IAA and increased during CFA. The findings in this study have provided a foundation for future studies to elucidate the roles of CitPGs in CFA.
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14
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Rafique S. Differential expression of leaf proteome of tolerant and susceptible maize ( Zea mays L.) genotypes in response to multiple abiotic stresses. Biochem Cell Biol 2019; 97:581-588. [PMID: 30807207 DOI: 10.1139/bcb-2018-0338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
In the present work, tropical maize genotypes were evaluated for multiple stresses (drought × low-N and waterlogging × low-N) applied simultaneously to 30-day-old maize seedlings. Two-dimensional gel electrophoresis was used to examine the protein changes induced by combined stress, in leaves, of tolerant and susceptible genotypes. Moreover, physiological and biochemical parameters were assessed to understand the physiological status of tolerant and susceptible genotypes under combined stress. The results show that up-regulated proteins of the tolerant genotype have a significant role in activating defense response, restoration of plant growth, and to maintain metabolic homeostasis under stressful conditions. Therefore, they contribute to improve and maintain the state of acclimation of the genotype under stress. Alternatively in the susceptible genotype, the up-regulated proteins are representative biomarkers of stress or are involved in the defense against pathogens and efforts to maintain energy metabolism. Thus, protecting the survival of the genotype under multiple stress conditions. We conclude that depending on the given stress treatment, tolerant and susceptible genotypes differed in stress-enduring approaches. Therefore, the study provides insight to comprehend the response of tolerant and susceptible genotypes under combined stress conditions, which could be valuable for further research and will demonstrate that it is advantageous to select combined stress-tolerant genotypes.
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Affiliation(s)
- Suphia Rafique
- Department of Biotechnology, Faculty of Chemicals and Life Sciences, Jamia Hamdard, New Delhi, 110062, India.,Department of Biotechnology, Faculty of Chemicals and Life Sciences, Jamia Hamdard, New Delhi, 110062, India
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15
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Ohashi T, Jinno J, Inoue Y, Ito S, Fujiyama K, Ishimizu T. A polygalacturonase localized in the Golgi apparatus in Pisum sativum. J Biochem 2017; 162:193-201. [PMID: 28338792 DOI: 10.1093/jb/mvx014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 01/30/2017] [Indexed: 11/13/2022] Open
Abstract
Pectin is a plant cell wall constituent that is mainly composed of polygalacturonic acid (PGA), a linear α1,4-d-galacturonic acid (GalUA) backbone. Polygalacturonase (PG) hydrolyzes the α1,4-linkages in PGA. Nearly all plant PGs identified thus far are secreted as soluble proteins. Here we describe the microsomal PG activity in pea (Pisum sativum) epicotyls and present biochemical evidence that it was localized to the Golgi apparatus, where pectins are biosynthesized. The microsomal PG was purified, and it was enzymatically characterized. The purified enzyme showed maximum activity towards pyridylaminated oligogalacturonic acids with six degrees of polymerization (PA-GalUA6), with a Km value of 11 μM for PA-GalUA6. The substrate preference of the enzyme was complementary to that of PGA synthase. The main PG activity in microsomes was detected in the Golgi fraction by sucrose density gradient ultracentrifugation. The activity of the microsomal PG was lower in rapidly growing epicotyls, in contrast to the high expression of PGA synthase. The role of this PG in the regulation of pectin biosynthesis or plant growth is discussed.
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Affiliation(s)
- Takao Ohashi
- International Center for Biotechnology, Osaka University, Suita, Osaka 565-0871, Japan
- Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Jun Jinno
- Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Yoshiyuki Inoue
- College of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan
| | - Shoko Ito
- Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Kazuhito Fujiyama
- International Center for Biotechnology, Osaka University, Suita, Osaka 565-0871, Japan
| | - Takeshi Ishimizu
- College of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan
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16
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Glazinska P, Wojciechowski W, Kulasek M, Glinkowski W, Marciniak K, Klajn N, Kesy J, Kopcewicz J. De novo Transcriptome Profiling of Flowers, Flower Pedicels and Pods of Lupinus luteus (Yellow Lupine) Reveals Complex Expression Changes during Organ Abscission. FRONTIERS IN PLANT SCIENCE 2017; 8:641. [PMID: 28512462 PMCID: PMC5412092 DOI: 10.3389/fpls.2017.00641] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 04/10/2017] [Indexed: 05/03/2023]
Abstract
Yellow lupine (Lupinus luteus L., Taper c.), a member of the legume family (Fabaceae L.), has an enormous practical importance. Its excessive flower and pod abscission represents an economic drawback, as proper flower and seed formation and development is crucial for the plant's productivity. Generative organ detachment takes place at the basis of the pedicels, within a specialized group of cells collectively known as the abscission zone (AZ). During plant growth these cells become competent to respond to specific signals that trigger separation and lead to the abolition of cell wall adhesion. Little is known about the molecular network controlling the yellow lupine organ abscission. The aim of our study was to establish the divergences and similarities in transcriptional networks in the pods, flowers and flower pedicels abscised or maintained on the plant, and to identify genes playing key roles in generative organ abscission in yellow lupine. Based on de novo transcriptome assembly, we identified 166,473 unigenes representing 219,514 assembled unique transcripts from flowers, flower pedicels and pods undergoing abscission and from control organs. Comparison of the cDNA libraries from dropped and control organs helped in identifying 1,343, 2,933 and 1,491 differentially expressed genes (DEGs) in the flowers, flower pedicels and pods, respectively. In DEG analyses, we focused on genes involved in phytohormonal regulation, cell wall functioning and metabolic pathways. Our results indicate that auxin, ethylene and gibberellins are some of the main factors engaged in generative organ abscission. Identified 28 DEGs common for all library comparisons are involved in cell wall functioning, protein metabolism, water homeostasis and stress response. Interestingly, among the common DEGs we also found an miR169 precursor, which is the first evidence of micro RNA engaged in abscission. A KEGG pathway enrichment analysis revealed that the identified DEGs were predominantly involved in carbohydrate and amino acid metabolism, but some other pathways were also targeted. This study represents the first comprehensive transcriptome-based characterization of organ abscission in L. luteus and provides a valuable data source not only for understanding the abscission signaling pathway in yellow lupine, but also for further research aimed at improving crop yields.
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Affiliation(s)
- Paulina Glazinska
- Department of Biology and Environmental Science, Nicolaus Copernicus UniversityTorun, Poland
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus UniversityTorun, Poland
| | - Waldemar Wojciechowski
- Department of Biology and Environmental Science, Nicolaus Copernicus UniversityTorun, Poland
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus UniversityTorun, Poland
| | - Milena Kulasek
- Department of Biology and Environmental Science, Nicolaus Copernicus UniversityTorun, Poland
| | - Wojciech Glinkowski
- Department of Biology and Environmental Science, Nicolaus Copernicus UniversityTorun, Poland
| | - Katarzyna Marciniak
- Department of Biology and Environmental Science, Nicolaus Copernicus UniversityTorun, Poland
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus UniversityTorun, Poland
| | - Natalia Klajn
- Department of Biology and Environmental Science, Nicolaus Copernicus UniversityTorun, Poland
| | - Jacek Kesy
- Department of Biology and Environmental Science, Nicolaus Copernicus UniversityTorun, Poland
| | - Jan Kopcewicz
- Department of Biology and Environmental Science, Nicolaus Copernicus UniversityTorun, Poland
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Han Y, Wan H, Cheng T, Wang J, Yang W, Pan H, Zhang Q. Comparative RNA-seq analysis of transcriptome dynamics during petal development in Rosa chinensis. Sci Rep 2017; 7:43382. [PMID: 28225056 PMCID: PMC5320579 DOI: 10.1038/srep43382] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 01/23/2017] [Indexed: 12/21/2022] Open
Abstract
The developmental process that produces the ornate petals of the China rose (Rosa chinensis) is complex and is thought to depend on the balanced expression of a functionally diverse array of genes; however, the molecular basis of rose petal development is largely unknown. Here, petal growth of the R. chinensis cultivar 'Old Blush' was divided into four developmental stages, and RNA-seq technology was used to analyse the dynamic changes in transcription that occur as development progresses. In total, 598 million clean reads and 61,456 successfully annotated unigenes were obtained. Differentially expressed gene (DEG) analysis comparing the transcriptomes of the developmental stages resulted in the identification of several potential candidate genes involved in petal development. DEGs involved in anthocyanin biosynthesis, petal expansion, and phytohormone pathways were considered in depth, in addition to several candidate transcription factors. These results lay a foundation for future studies on the regulatory mechanisms underlying rose petal development and may be used in molecular breeding programs aimed at generating ornamental rose lines with desirable traits.
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Affiliation(s)
- Yu Han
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation &Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Huihua Wan
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation &Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Tangren Cheng
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation &Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Jia Wang
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation &Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Weiru Yang
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation &Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Huitang Pan
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation &Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Qixiang Zhang
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation &Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
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18
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Merelo P, Agustí J, Arbona V, Costa ML, Estornell LH, Gómez-Cadenas A, Coimbra S, Gómez MD, Pérez-Amador MA, Domingo C, Talón M, Tadeo FR. Cell Wall Remodeling in Abscission Zone Cells during Ethylene-Promoted Fruit Abscission in Citrus. FRONTIERS IN PLANT SCIENCE 2017; 8:126. [PMID: 28228766 PMCID: PMC5296326 DOI: 10.3389/fpls.2017.00126] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 01/20/2017] [Indexed: 05/20/2023]
Abstract
Abscission is a cell separation process by which plants can shed organs such as fruits, leaves, or flowers. The process takes place in specific locations termed abscission zones. In fruit crops like citrus, fruit abscission represents a high percentage of annual yield losses. Thus, understanding the molecular regulation of abscission is of capital relevance to control production. To identify genes preferentially expressed within the citrus fruit abscission zone (AZ-C), we performed a comparative transcriptomics assay at the cell type resolution level between the AZ-C and adjacent fruit rind cells (non-abscising tissue) during ethylene-promoted abscission. Our strategy combined laser microdissection with microarray analysis. Cell wall modification-related gene families displayed prominent representation in the AZ-C. Phylogenetic analyses of such gene families revealed a link between phylogenetic proximity and expression pattern during abscission suggesting highly conserved roles for specific members of these families in abscission. Our transcriptomic data was validated with (and strongly supported by) a parallel approach consisting on anatomical, histochemical and biochemical analyses on the AZ-C during fruit abscission. Our work identifies genes potentially involved in organ abscission and provides relevant data for future biotechnology approaches aimed at controlling such crucial process for citrus yield.
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Affiliation(s)
- Paz Merelo
- Centre de Genòmica, Institut Valencià d' AgràriesValència, Spain
| | - Javier Agustí
- Centre de Genòmica, Institut Valencià d' AgràriesValència, Spain
| | - Vicent Arbona
- Centre de Genòmica, Institut Valencià d' AgràriesValència, Spain
| | - Mário L. Costa
- Departamento de Biologia, Faculdade de Ciências, Universidade do PortoPorto, Portugal
| | | | - Aurelio Gómez-Cadenas
- Departament de Ciències Agràries i del Medi Natural, Universitat Jaume ICastelló de la Plana, Spain
| | - Silvia Coimbra
- Departamento de Biologia, Faculdade de Ciências, Universidade do PortoPorto, Portugal
| | - María D. Gómez
- Departamento de Desarrollo y Acción Hormonal en Plantas, Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones CientíficasValencia, Spain
| | - Miguel A. Pérez-Amador
- Departamento de Desarrollo y Acción Hormonal en Plantas, Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones CientíficasValencia, Spain
| | - Concha Domingo
- Centre de Genòmica, Institut Valencià d' AgràriesValència, Spain
| | - Manuel Talón
- Centre de Genòmica, Institut Valencià d' AgràriesValència, Spain
| | - Francisco R. Tadeo
- Centre de Genòmica, Institut Valencià d' AgràriesValència, Spain
- *Correspondence: Francisco R. Tadeo
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19
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Qian M, Zhang Y, Yan X, Han M, Li J, Li F, Li F, Zhang D, Zhao C. Identification and Expression Analysis of Polygalacturonase Family Members during Peach Fruit Softening. Int J Mol Sci 2016; 17:E1933. [PMID: 27869753 PMCID: PMC5133928 DOI: 10.3390/ijms17111933] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 11/02/2016] [Accepted: 11/07/2016] [Indexed: 01/01/2023] Open
Abstract
Polygalacturonase (PG) is an important hydrolytic enzyme involved in pectin degradation during fruit softening. However, the roles of PG family members in fruit softening remain unclear. We identified 45 PpPG genes in the peach genome which are clustered into six subclasses. PpPGs consist of four to nine exons and three to eight introns, and the exon/intron structure is basically conserved in all but subclass E. Only 16 PpPG genes were expressed in ripening fruit, and their expression profiles were analyzed during storage in two peach cultivars with different softening characteristics. Eight PGs (PpPG1, -10, -12, -13, -15, -23, -21, and -22) in fast-softening "Qian Jian Bai" (QJB) fruit and three PGs (PpPG15, -21, and -22) in slow-softening "Qin Wang" (QW) fruit exhibited softening-associated patterns; which also were affected by ethylene treatment. Our results suggest that the different softening characters in QW and QJB fruit is related to the amount of PG members. While keeping relatively lower levels during QW fruit softening, the expression of six PGs (PpPG1, -10, -12, -11, -14, and -35) rapidly induced by ethylene. PpPG24, -25 and -38 may not be involved in softening of peach fruit.
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Affiliation(s)
- Ming Qian
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Yike Zhang
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Xiangyan Yan
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Mingyu Han
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Jinjin Li
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Fang Li
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Furui Li
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Dong Zhang
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Caiping Zhao
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
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Latarullo MBG, Tavares EQP, Padilla G, Leite DCC, Buckeridge MS. Pectins, Endopolygalacturonases, and Bioenergy. FRONTIERS IN PLANT SCIENCE 2016; 7:1401. [PMID: 27703463 PMCID: PMC5028389 DOI: 10.3389/fpls.2016.01401] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Accepted: 09/02/2016] [Indexed: 05/25/2023]
Abstract
The precise disassembly of the extracellular matrix of some plant species used as feedstocks for bioenergy production continues to be a major barrier to reach reasonable cost effective bioethanol production. One solution has been the use of pretreatments, which can be effective, but increase even more the cost of processing and also lead to loss of cell wall materials that could otherwise be used in industry. Although pectins are known to account for a relatively low proportion of walls of grasses, their role in recalcitrance to hydrolysis has been shown to be important. In this mini-review, we examine the importance of pectins for cell wall hydrolysis highlighting the work associated with bioenergy. Here we focus on the importance of endopolygalacturonases (EPGs) discovered to date. The EPGs cataloged by CAZy were screened, revealing that most sequences, as well as the scarce structural work performed with EPGs, are from fungi (mostly Aspergillus niger). The comparisons among the EPG from different microorganisms, suggests that EPGs from bacteria and grasses display higher similarity than each of them with fungi. This compilation strongly suggests that structural and functional studies of EPGs, mainly from plants and bacteria, should be a priority of research regarding the use of pectinases for bioenergy production purposes.
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Affiliation(s)
- Mariana B. G. Latarullo
- Laboratory of Plant Physiological Ecology, Department of Botany, Institute of Biosciences, University of São PauloSão Paulo, Brazil
- Bioproducts Laboratory, Department of Microbiology, Institute of Biomedical Sciences, University of São PauloSão Paulo, Brazil
| | - Eveline Q. P. Tavares
- Laboratory of Plant Physiological Ecology, Department of Botany, Institute of Biosciences, University of São PauloSão Paulo, Brazil
| | - Gabriel Padilla
- Bioproducts Laboratory, Department of Microbiology, Institute of Biomedical Sciences, University of São PauloSão Paulo, Brazil
| | - Débora C. C. Leite
- Laboratory of Plant Physiological Ecology, Department of Botany, Institute of Biosciences, University of São PauloSão Paulo, Brazil
| | - Marcos S. Buckeridge
- Laboratory of Plant Physiological Ecology, Department of Botany, Institute of Biosciences, University of São PauloSão Paulo, Brazil
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21
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Lee Y, Ayeh KO, Ambrose M, Hvoslef-Eide AK. Immunolocalization of pectic polysaccharides during abscission in pea seeds (Pisum sativum L.) and in abscission less def pea mutant seeds. BMC Res Notes 2016; 9:427. [PMID: 27581466 PMCID: PMC5007855 DOI: 10.1186/s13104-016-2231-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 08/19/2016] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND In pea seeds (Pisum sativum L.), the presence of the Def locus determines abscission event between its funicle and the seed coat. Cell wall remodeling is a necessary condition for abscission of pea seed. The changes in cell wall components in wild type (WT) pea seed with Def loci showing seed abscission and in abscission less def mutant peas were studied to identify the factors determining abscission and non-abscission event. METHODS Changes in pectic polysaccharides components were investigated in WT and def mutant pea seeds using immunolabeling techniques. Pectic monoclonal antibodies (1 → 4)-β-D-galactan (LM5), (1 → 5)-α-L-arabinan(LM6), partially de-methyl esterified homogalacturonan (HG) (JIM5) and methyl esterified HG (JIM7) were used for this study. RESULTS Prior to abscission zone (AZ) development, galactan and arabinan reduced in the predestined AZ of the pea seed and disappeared during the abscission process. The AZ cells had partially de-methyl esterified HG while other areas had highly methyl esterified HG. A strong JIM5 labeling in the def mutant may be related to cell wall rigidity in the mature def mutants. In addition, the appearance of pectic epitopes in two F3 populations resulting from cross between WT and def mutant parents was studied. As a result, we identified that homozygous dominant lines (Def/Def) showing abscission and homozygous recessive lines (def/def) showing non-abscission had similar immunolabeling pattern to their parents. However, the heterogeneous lines (Def/def) showed various immunolabeling pattern and the segregation pattern of the Def locus. CONCLUSIONS Through the study of the complexity and variability of pectins in plant cell walls as well as understanding the segregation patterns of the Def locus using immunolabeling techniques, we conclude that cell wall remodeling occurs in the abscission process and de-methyl esterification may play a role in the non-abscission event in def mutant. Overall, this study contributes new insights into understanding the structural and architectural organization of the cell walls during abscission.
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Affiliation(s)
- YeonKyeong Lee
- Department of Plant Sciences, Norwegian University of Life Sciences (NMBU), P.O. BOX 5003, 1432 Ås, Norway
| | - Kwadwo Owusu Ayeh
- Department of Botany, School of Biological Sciences, College of Basic and Applied Sciences, University of Ghana, Legon-Accra, Ghana
| | - Mike Ambrose
- Department of Crops Genetics, John Innes Centre, Norwich Research Park, Colney Lane, NR4 7UH Norwich, UK
| | - Anne Kathrine Hvoslef-Eide
- Department of Plant Sciences, Norwegian University of Life Sciences (NMBU), P.O. BOX 5003, 1432 Ås, Norway
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Patterson SE, Bolivar-Medina JL, Falbel TG, Hedtcke JL, Nevarez-McBride D, Maule AF, Zalapa JE. Are We on the Right Track: Can Our Understanding of Abscission in Model Systems Promote or Derail Making Improvements in Less Studied Crops? FRONTIERS IN PLANT SCIENCE 2016; 6:1268. [PMID: 26858730 PMCID: PMC4726918 DOI: 10.3389/fpls.2015.01268] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 12/28/2015] [Indexed: 05/24/2023]
Abstract
As the world population grows and resources and climate conditions change, crop improvement continues to be one of the most important challenges for agriculturalists. The yield and quality of many crops is affected by abscission or shattering, and environmental stresses often hasten or alter the abscission process. Understanding this process can not only lead to genetic improvement, but also changes in cultural practices and management that will contribute to higher yields, improved quality and greater sustainability. As plant scientists, we have learned significant amounts about this process through the study of model plants such as Arabidopsis, tomato, rice, and maize. While these model systems have provided significant valuable information, we are sometimes challenged to use this knowledge effectively as variables including the economic value of the crop, the uniformity of the crop, ploidy levels, flowering and crossing mechanisms, ethylene responses, cultural requirements, responses to changes in environment, and cellular and tissue specific morphological differences can significantly influence outcomes. The value of genomic resources for lesser-studied crops such as cranberries and grapes and the orphan crop fonio will also be considered.
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Affiliation(s)
- Sara E. Patterson
- Department of Horticulture, University of Wisconsin–MadisonMadison, WI, USA
| | - Jenny L. Bolivar-Medina
- Department of Horticulture, University of Wisconsin–MadisonMadison, WI, USA
- Vegetable Crops Research Unit, United States Department of Agriculture – Agricultural Research ServiceMadison, WI, USA
| | - Tanya G. Falbel
- Department of Horticulture, University of Wisconsin–MadisonMadison, WI, USA
| | | | | | - Andrew F. Maule
- Department of Horticulture, University of Wisconsin–MadisonMadison, WI, USA
| | - Juan E. Zalapa
- Department of Horticulture, University of Wisconsin–MadisonMadison, WI, USA
- Vegetable Crops Research Unit, United States Department of Agriculture – Agricultural Research ServiceMadison, WI, USA
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Wang GQ, Wei PC, Tan F, Yu M, Zhang XY, Chen QJ, Wang XC. The Transcription Factor AtDOF4.7 Is Involved in Ethylene- and IDA-Mediated Organ Abscission in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2016; 7:863. [PMID: 27379143 PMCID: PMC4911407 DOI: 10.3389/fpls.2016.00863] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 06/01/2016] [Indexed: 05/20/2023]
Abstract
Organ abscission is an important plant developmental process that occurs in response to environmental stress or pathogens. In Arabidopsis, ligand signals, such as ethylene or INFLORESCENCE DEFICIENT IN ABSCISSION (IDA), can regulate organ abscission. Previously, we reported that overexpression of AtDOF4.7, a transcription factor gene, directly suppresses the expression of the abscission-related gene ARABIDOPSIS DEHISCENCE ZONE POLYGALACTURONASE 2 (ADPG2), resulting in a deficiency of floral organ abscission. However, the relationship between AtDOF4.7 and abscission pathways still needs to be investigated. In this study, we showed that ethylene regulates the expression of AtDOF4.7, and the peptide ligand, IDA negatively regulates AtDOF4.7 at the transcriptional level. Genetic evidence indicates that AtDOF4.7 and IDA are involved in a common pathway, and a MAPK cascade can phosphorylate AtDOF4.7 in vitro. Further in vivo data suggest that AtDOF4.7 protein levels may be regulated by this phosphorylation. Collectively, our results indicate that ethylene regulates AtDOF4.7 that is involved in the IDA-mediated floral organ abscission pathway.
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Affiliation(s)
- Gao-Qi Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural UniversityBeijing, China
| | - Peng-Cheng Wei
- Rice Research Institution, AnHui Academy of Agricultural SciencesHefei, China
| | - Feng Tan
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural UniversityBeijing, China
| | - Man Yu
- Department of Food and Biological Technology, College of Food Science and Nutritional Engineering, China Agricultural UniversityBeijing, China
| | - Xiao-Yan Zhang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural UniversityBeijing, China
| | - Qi-Jun Chen
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural UniversityBeijing, China
| | - Xue-Chen Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural UniversityBeijing, China
- *Correspondence: Xue-Chen Wang,
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24
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Eccher G, Begheldo M, Boschetti A, Ruperti B, Botton A. Roles of Ethylene Production and Ethylene Receptor Expression in Regulating Apple Fruitlet Abscission. PLANT PHYSIOLOGY 2015; 169:125-37. [PMID: 25888617 PMCID: PMC4577387 DOI: 10.1104/pp.15.00358] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 04/15/2015] [Indexed: 05/05/2023]
Abstract
Apple (Malus × domestica) is increasingly being considered an interesting model species for studying early fruit development, during which an extremely relevant phenomenon, fruitlet abscission, may occur as a response to both endogenous and/or exogenous cues. Several studies were carried out shedding light on the main physiological and molecular events leading to the selective release of lateral fruitlets within a corymb, either occurring naturally or as a result of a thinning treatment. Several studies pointed out a clear association between a rise of ethylene biosynthetic levels in the fruitlet and its tendency to abscise. A direct mechanistic link, however, has not yet been established between this gaseous hormone and the generation of the abscission signal within the fruit. In this work, the role of ethylene during the very early stages of abscission induction was investigated in fruitlet populations with different abscission potentials due either to the natural correlative inhibitions determining the so-called physiological fruit drop or to a well-tested thinning treatment performed with the cytokinin benzyladenine. A crucial role was ascribed to the ratio between the ethylene produced by the cortex and the expression of ethylene receptor genes in the seed. This ratio would determine the final probability to abscise. A working model has been proposed consistent with the differential distribution of four receptor transcripts within the seed, which resembles a spatially progressive cell-specific immune-like mechanism evolved by apple to protect the embryo from harmful ethylene.
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Affiliation(s)
- Giulia Eccher
- Department of Agronomy, Food, Natural Resources, Animals, and Environment, University of Padova, Agripolis, 35020 Legnaro, Italy (G.E., M.B., B.R., A.Bot.); andNanoscience Research Unit, Bruno Kessler Foundation, National Research Council-Institute of Materials for Electronics and Magnetism, 38123 Trento, Italy (A.Bos.)
| | - Maura Begheldo
- Department of Agronomy, Food, Natural Resources, Animals, and Environment, University of Padova, Agripolis, 35020 Legnaro, Italy (G.E., M.B., B.R., A.Bot.); andNanoscience Research Unit, Bruno Kessler Foundation, National Research Council-Institute of Materials for Electronics and Magnetism, 38123 Trento, Italy (A.Bos.)
| | - Andrea Boschetti
- Department of Agronomy, Food, Natural Resources, Animals, and Environment, University of Padova, Agripolis, 35020 Legnaro, Italy (G.E., M.B., B.R., A.Bot.); andNanoscience Research Unit, Bruno Kessler Foundation, National Research Council-Institute of Materials for Electronics and Magnetism, 38123 Trento, Italy (A.Bos.)
| | - Benedetto Ruperti
- Department of Agronomy, Food, Natural Resources, Animals, and Environment, University of Padova, Agripolis, 35020 Legnaro, Italy (G.E., M.B., B.R., A.Bot.); andNanoscience Research Unit, Bruno Kessler Foundation, National Research Council-Institute of Materials for Electronics and Magnetism, 38123 Trento, Italy (A.Bos.)
| | - Alessandro Botton
- Department of Agronomy, Food, Natural Resources, Animals, and Environment, University of Padova, Agripolis, 35020 Legnaro, Italy (G.E., M.B., B.R., A.Bot.); andNanoscience Research Unit, Bruno Kessler Foundation, National Research Council-Institute of Materials for Electronics and Magnetism, 38123 Trento, Italy (A.Bos.)
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25
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Cheng C, Zhang L, Yang X, Zhong G. Profiling gene expression in citrus fruit calyx abscission zone (AZ-C) treated with ethylene. Mol Genet Genomics 2015; 290:1991-2006. [PMID: 25948248 DOI: 10.1007/s00438-015-1054-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 04/20/2015] [Indexed: 02/06/2023]
Abstract
On-tree storage and harvesting of mature fruit account for a large proportion of cost in the production of citrus, and a reduction of the cost would not be achieved without a thorough understanding of the mechani sm of the mature fruit abscission. Genome-wide gene expression changes in ethylene-treated fruit calyx abscission zone (AZ-C) of Citrus sinensis cv. Olinda were therefore investigated using a citrus genome array representing up to 33,879 citrus transcripts. In total, 1313 and 1044 differentially regulated genes were identified in AZ-C treated with ethylene for 4 and 24 h, respectively. The results showed that mature citrus fruit abscission commenced with the activation of ethylene signal transduction pathway that led to the activation of ethylene responsive transcription factors and the subsequent transcriptional regulation of a large set of ethylene responsive genes. Significantly down-regulated genes included those of starch/sugar biosynthesis, transportation of water and growth promoting hormone synthesis and signaling, whereas significantly up-regulated genes were those involved in defense, cell wall degradation, and secondary metabolism. Our data unraveled the underlying mechanisms of some known important biochemical events occurring at AZ-C and should provide informative suggestions for future manipulation of the events to achieve a controllable abscission for mature citrus fruit.
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Affiliation(s)
- Chunzhen Cheng
- Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences Guangzhou, Guangdong, 510640, People's Republic of China. .,College of Horticulture and Landscape Architecture, Southwest University, Beibei, Chongqing, 400715, People's Republic of China. .,Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization Ministry of Agriculture Guangzhou, Guangdong, 510640, People's Republic of China. .,Key Laboratory of Tropical and Subtropical Fruit tree Researches, Guangdong Province Guangzhou, Guangdong, 510640, People's Republic of China.
| | - Lingyun Zhang
- School of Geographic and Environmental Sciences, Guizhou Normal University Guizhou, Guiyang, 550001, People's Republic of China
| | - Xuelian Yang
- College of Agriculture, Guizhou University Guiyang, Guizhou, 550025, People's Republic of China
| | - Guangyan Zhong
- Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences Guangzhou, Guangdong, 510640, People's Republic of China. .,Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization Ministry of Agriculture Guangzhou, Guangdong, 510640, People's Republic of China. .,Key Laboratory of Tropical and Subtropical Fruit tree Researches, Guangdong Province Guangzhou, Guangdong, 510640, People's Republic of China.
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26
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Sawicki M, Aït Barka E, Clément C, Vaillant-Gaveau N, Jacquard C. Cross-talk between environmental stresses and plant metabolism during reproductive organ abscission. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:1707-19. [PMID: 25711702 PMCID: PMC4669552 DOI: 10.1093/jxb/eru533] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 12/04/2014] [Accepted: 12/09/2014] [Indexed: 05/06/2023]
Abstract
In plants, flowering is a crucial process for reproductive success and continuity of the species through time. Fruit production requires the perfect development of reproductive structures. Abscission, a natural process, can occur to facilitate shedding of no longer needed, infected, or damaged organs. If stress occurs during flower development, abscission can intervene at flower level, leading to reduced yield. Flower abscission is a highly regulated developmental process simultaneously influenced and activated in response to exogenous (changing environmental conditions, interactions with microorganisms) and endogenous (physiological modifications) stimuli. During climate change, plant communities will be more susceptible to environmental stresses, leading to increased flower and fruit abscission, and consequently a decrease in fruit yield. Understanding the impacts of stress on the reproductive phase is therefore critical for managing future agricultural productivity. Here, current knowledge on flower/fruit abscission is summarized by focusing specifically on effects of environmental stresses leading to this process in woody plants. Many of these stresses impair hormonal balance and/or carbohydrate metabolism, but the exact mechanisms are far from completely known. Hormones are the abscission effectors and the auxin/ethylene balance is of particular importance. The carbohydrate pathway is the result of complex regulatory processes involving the balance between photosynthesis and mobilization of reserves. Hormones and carbohydrates together participate in complex signal transduction systems, especially in response to stress. The available data are discussed in relation to reproductive organ development and the process of abscission.
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Affiliation(s)
- Mélodie Sawicki
- Université de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Unité de Recherche Vignes et Vins de Champagne - EA 4707, Moulin de la Housse - Bâtiment 18, BP 1039, 51687 Reims Cedex 2, France
| | - Essaïd Aït Barka
- Université de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Unité de Recherche Vignes et Vins de Champagne - EA 4707, Moulin de la Housse - Bâtiment 18, BP 1039, 51687 Reims Cedex 2, France
| | - Christophe Clément
- Université de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Unité de Recherche Vignes et Vins de Champagne - EA 4707, Moulin de la Housse - Bâtiment 18, BP 1039, 51687 Reims Cedex 2, France
| | - Nathalie Vaillant-Gaveau
- Université de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Unité de Recherche Vignes et Vins de Champagne - EA 4707, Moulin de la Housse - Bâtiment 18, BP 1039, 51687 Reims Cedex 2, France
| | - Cédric Jacquard
- Université de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Unité de Recherche Vignes et Vins de Champagne - EA 4707, Moulin de la Housse - Bâtiment 18, BP 1039, 51687 Reims Cedex 2, France
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27
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Sundaresan S, Philosoph-Hadas S, Riov J, Belausov E, Kochanek B, Tucker ML, Meir S. Abscission of flowers and floral organs is closely associated with alkalization of the cytosol in abscission zone cells. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:1355-68. [PMID: 25504336 PMCID: PMC4339595 DOI: 10.1093/jxb/eru483] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
In vivo changes in the cytosolic pH of abscission zone (AZ) cells were visualized using confocal microscopic detection of the fluorescent pH-sensitive and intracellularly trapped dye, 2',7'-bis-(2-carboxyethyl)-5(and-6)-carboxyfluorescein (BCECF), driven by its acetoxymethyl ester. A specific and gradual increase in the cytosolic pH of AZ cells was observed during natural abscission of flower organs in Arabidopsis thaliana and wild rocket (Diplotaxis tenuifolia), and during flower pedicel abscission induced by flower removal in tomato (Solanum lycopersicum Mill). The alkalization pattern in the first two species paralleled the acceleration or inhibition of flower organ abscission induced by ethylene or its inhibitor 1-methylcyclopropene (1-MCP), respectively. Similarly, 1-MCP pre-treatment of tomato inflorescence explants abolished the pH increase in AZ cells and pedicel abscission induced by flower removal. Examination of the pH changes in the AZ cells of Arabidopsis mutants defective in both ethylene-induced (ctr1, ein2, eto4) and ethylene-independent (ida, nev7, dab5) abscission pathways confirmed these results. The data indicate that the pH changes in the AZ cells are part of both the ethylene-sensitive and -insensitive abscission pathways, and occur concomitantly with the execution of organ abscission. pH can affect enzymatic activities and/or act as a signal for gene expression. Changes in pH during abscission could occur via regulation of transporters in AZ cells, which might affect cytosolic pH. Indeed, four genes associated with pH regulation, vacuolar H(+)-ATPase, putative high-affinity nitrate transporter, and two GTP-binding proteins, were specifically up-regulated in tomato flower AZ following abscission induction, and 1-MCP reduced or abolished the increased expression.
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Affiliation(s)
- Srivignesh Sundaresan
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), The Volcani Center, Bet-Dagan 5025001, Israel The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Sonia Philosoph-Hadas
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), The Volcani Center, Bet-Dagan 5025001, Israel
| | - Joseph Riov
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Eduard Belausov
- Department of Ornamental Horticulture, Agricultural Research Organization (ARO), The Volcani Center, Bet-Dagan 5025001, Israel
| | - Betina Kochanek
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), The Volcani Center, Bet-Dagan 5025001, Israel
| | - Mark L Tucker
- Soybean Genomics and Improvement Laboratory, USDA-ARS, Beltsville, MD 20705, USA
| | - Shimon Meir
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), The Volcani Center, Bet-Dagan 5025001, Israel
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28
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Yan H, Ma L, Wang Z, Lin Z, Su J, Lu BR. Multiple tissue-specific expression of rice seed-shattering gene SH4 regulated by its promoter pSH4. RICE (NEW YORK, N.Y.) 2015; 8:12. [PMID: 25844117 PMCID: PMC4384984 DOI: 10.1186/s12284-015-0047-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 02/02/2015] [Indexed: 05/10/2023]
Abstract
BACKGROUND Rice seed shattering is an important domestication syndrome encoded by a gene named as SH4. The coding region of SH4 has been well studied regarding its function and roles in evolution. However, its promoter has not been identified, which limited our understanding of the detailed regulatory mechanisms of this gene. It is therefore critical to characterize the promoter and study its expression pattern. RESULTS We analyzed the 5' upstream sequences of this gene and identified a ~2.6 kb fragment with typical promoter features, which was designated as pSH4. The promoter contained a number of cis-acting elements related to abscisic acid (ABA) and a CpG island that were characteristics of multiple tissue-specific expression. We isolated and ligated pSH4 to the β-glucuronidase (GUS) reporter gene, and transformed it into a japonica rice cultivar to determine the multiple expression pattern of SH4. Histochemical location and fluorescence analyses of GUS activity of transgenic plants indicated multiple tissue-specific expression of pSH4 in the seed-pedicel junction region of mature panicles (with highest level), stems, coleoptiles of germinated seeds, and scutella of mature seeds. CONCLUSIONS The multiple tissue-specific expression pSH4 is categorized as a spatiotemporal promoter that drives the expression of the SH4 gene in different rice tissues, in addition to the seed-pedicel junction region. Our findings suggest that SH4 may have additional functions in the growth and development of rice, apart from its major role in seed shattering.
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Affiliation(s)
- Huanxin Yan
- />Ministry of Education Key Laboratory for Biodiversity and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Songhu Road 2005, Shanghai, 200436 China
| | - Li Ma
- />Ministry of Education Key Laboratory for Biodiversity and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Songhu Road 2005, Shanghai, 200436 China
| | - Zhe Wang
- />Ministry of Education Key Laboratory for Biodiversity and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Songhu Road 2005, Shanghai, 200436 China
| | - Zhimin Lin
- />Fujian Province Key Laboratory of Genetic Engineering for Agriculture, Fujian Academy of Agricultural Sciences, Wusi Road 247, Fuzhou, 350003 China
| | - Jun Su
- />Fujian Province Key Laboratory of Genetic Engineering for Agriculture, Fujian Academy of Agricultural Sciences, Wusi Road 247, Fuzhou, 350003 China
| | - Bao-Rong Lu
- />Ministry of Education Key Laboratory for Biodiversity and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Songhu Road 2005, Shanghai, 200436 China
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Tsuchiya M, Satoh S, Iwai H. Distribution of XTH, expansin, and secondary-wall-related CesA in floral and fruit abscission zones during fruit development in tomato (Solanum lycopersicum). FRONTIERS IN PLANT SCIENCE 2015; 6:323. [PMID: 26029225 PMCID: PMC4432578 DOI: 10.3389/fpls.2015.00323] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 04/24/2015] [Indexed: 05/11/2023]
Abstract
After fruit development is triggered by pollination, the abscission zone (AZ) in the fruit pedicel strengthens its adhesion to keep the fruit attached. We previously reported that xyloglucan and arabinan accumulation in the AZ accompanies the shedding of unpollinated flowers. After the fruit has developed and is fully ripened, shedding occurs easily in the AZ due to lignin accumulation. Regulation of cell wall metabolism may play an important role in these processes, but it is not well understood. In the present report, we used immunohistochemistry to visualize changes in the distributions of xyloglucan and arabinan metabolism-related enzymes in the AZs of pollinated and unpollinated flowers, and in ripened fruits. During floral abscission, we observed a gradual increase in polyclonal antibody labeling of expansin in the AZ. The intensities of LM6 and LM15 labeling of arabinan and xyloglucan, respectively, also increased. However, during floral abscission, we observed a large 1 day post anthesis (DPA) peak in the polyclonal antibody labeling of XTH in the AZ, which then decreased. These results suggest that expansin and XTH play important, but different roles in the floral abscission process. During fruit abscission, unlike during floral abscission, no AZ-specific expansin and XTH were observed. Although lignification was seen in the AZ of over-ripe fruit pedicels, secondary cell wall-specific cellulose synthase signals were not observed. This suggests that cellulose metabolism-related enzymes do not play important roles in the AZ prior to fruit abscission.
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Affiliation(s)
- Mutsumi Tsuchiya
- Faculty of Life and Environmental Sciences, University of Tsukuba , Tsukuba, Japan
| | - Shinobu Satoh
- Faculty of Life and Environmental Sciences, University of Tsukuba , Tsukuba, Japan
| | - Hiroaki Iwai
- Faculty of Life and Environmental Sciences, University of Tsukuba , Tsukuba, Japan
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Zhang JZ, Zhao K, Ai XY, Hu CG. Involvements of PCD and changes in gene expression profile during self-pruning of spring shoots in sweet orange (Citrus sinensis). BMC Genomics 2014; 15:892. [PMID: 25308090 PMCID: PMC4209071 DOI: 10.1186/1471-2164-15-892] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 09/24/2014] [Indexed: 12/21/2022] Open
Abstract
Background Citrus shoot tips abscise at an anatomically distinct abscission zone (AZ) that separates the top part of the shoots into basal and apical portions (citrus self-pruning). Cell separation occurs only at the AZ, which suggests its cells have distinctive molecular regulation. Although several studies have looked into the morphological aspects of self-pruning process, the underlying molecular mechanisms remain unknown. Results In this study, the hallmarks of programmed cell death (PCD) were identified by TUNEL experiments, transmission electron microscopy (TEM) and histochemical staining for reactive oxygen species (ROS) during self-pruning of the spring shoots in sweet orange. Our results indicated that PCD occurred systematically and progressively and may play an important role in the control of self-pruning of citrus. Microarray analysis was used to examine transcriptome changes at three stages of self-pruning, and 1,378 differentially expressed genes were identified. Some genes were related to PCD, while others were associated with cell wall biosynthesis or metabolism. These results strongly suggest that abscission layers activate both catabolic and anabolic wall modification pathways during the self-pruning process. In addition, a strong correlation was observed between self-pruning and the expression of hormone-related genes. Self-pruning plays an important role in citrus floral bud initiation. Therefore, several key flowering homologs of Arabidopsis and tomato shoot apical meristem (SAM) activity genes were investigated in sweet orange by real-time PCR and in situ hybridization, and the results indicated that these genes were preferentially expressed in SAM as well as axillary meristem. Conclusion Based on these findings, a model for sweet orange spring shoot self-pruning is proposed, which will enable us to better understand the mechanism of self-pruning and abscission. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-892) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | - Chun-Gen Hu
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China.
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Sénéchal F, Wattier C, Rustérucci C, Pelloux J. Homogalacturonan-modifying enzymes: structure, expression, and roles in plants. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:5125-60. [PMID: 25056773 PMCID: PMC4400535 DOI: 10.1093/jxb/eru272] [Citation(s) in RCA: 155] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/20/2014] [Accepted: 05/22/2014] [Indexed: 05/18/2023]
Abstract
Understanding the changes affecting the plant cell wall is a key element in addressing its functional role in plant growth and in the response to stress. Pectins, which are the main constituents of the primary cell wall in dicot species, play a central role in the control of cellular adhesion and thereby of the rheological properties of the wall. This is likely to be a major determinant of plant growth. How the discrete changes in pectin structure are mediated is thus a key issue in our understanding of plant development and plant responses to changes in the environment. In particular, understanding the remodelling of homogalacturonan (HG), the most abundant pectic polymer, by specific enzymes is a current challenge in addressing its fundamental role. HG, a polymer that can be methylesterified or acetylated, can be modified by HGMEs (HG-modifying enzymes) which all belong to large multigenic families in all species sequenced to date. In particular, both the degrees of substitution (methylesterification and/or acetylation) and polymerization can be controlled by specific enzymes such as pectin methylesterases (PMEs), pectin acetylesterases (PAEs), polygalacturonases (PGs), or pectate lyases-like (PLLs). Major advances in the biochemical and functional characterization of these enzymes have been made over the last 10 years. This review aims to provide a comprehensive, up to date summary of the recent data concerning the structure, regulation, and function of these fascinating enzymes in plant development and in response to biotic stresses.
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Affiliation(s)
- Fabien Sénéchal
- EA3900 BIOPI Biologie des Plantes et Innovation, Université de Picardie Jules Verne, 33 Rue St Leu, F-80039 Amiens, France
| | - Christopher Wattier
- EA3900 BIOPI Biologie des Plantes et Innovation, Université de Picardie Jules Verne, 33 Rue St Leu, F-80039 Amiens, France
| | - Christine Rustérucci
- EA3900 BIOPI Biologie des Plantes et Innovation, Université de Picardie Jules Verne, 33 Rue St Leu, F-80039 Amiens, France
| | - Jérôme Pelloux
- EA3900 BIOPI Biologie des Plantes et Innovation, Université de Picardie Jules Verne, 33 Rue St Leu, F-80039 Amiens, France
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Du M, Li Y, Tian X, Duan L, Zhang M, Tan W, Xu D, Li Z. The phytotoxin coronatine induces abscission-related gene expression and boll ripening during defoliation of cotton. PLoS One 2014; 9:e97652. [PMID: 24845465 PMCID: PMC4028243 DOI: 10.1371/journal.pone.0097652] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Accepted: 04/21/2014] [Indexed: 01/26/2023] Open
Abstract
Defoliants can increase machine harvest efficiency of cotton (Gossypium hirusutum L.), prevent lodging and reduce the time from defoliation to harvest. Coronatine (COR) is a chlorosis-inducing non-host-specific phytotoxin that induces leaf and/or fruit abscission in some crops. The present study investigates how COR might induce cotton leaf abscission by modulating genes involved in cell wall hydrolases and ACC (ethylene precursor) in various cotton tissues. The effects of COR on cotton boll ripening, seedcotton yield, and seed development were also studied. After 14 d of treatment with COR, cells within the leaf abscission zone (AZ) showed marked differentiation. Elevated transcripts of GhCEL1, GhPG and GhACS were observed in the AZs treated with COR and Thidiazuron (TDZ). The relative expression of GhCEL1 and GhACS in TDZ treated plants was approximately twice that in plants treated with COR for 12 h. However, only GhACS expression increased in leaf blade and petiole. There was a continuous increase in the activity of hydrolytic enzymes such as cellulase (CEL) and polygalacturonase (PG), and ACC accumulation in AZs following COR and TDZ treatments, but there was greater increase in ACC activity of COR treated boll crust, indicating that COR had greater ripening effect than TDZ. Coronatine significantly enhanced boll opening without affecting boll weight, lint percentage and seed quality. Therefore, COR can be a potential cotton defoliant with different physiological mechanism of action from the currently used TDZ.
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Affiliation(s)
- Mingwei Du
- State Key Laboratory of Plant Physiology and Biochemistry, Engineering Research Center of Plant Growth Regulator, Ministry of Education, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Yi Li
- State Key Laboratory of Plant Physiology and Biochemistry, Engineering Research Center of Plant Growth Regulator, Ministry of Education, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Xiaoli Tian
- State Key Laboratory of Plant Physiology and Biochemistry, Engineering Research Center of Plant Growth Regulator, Ministry of Education, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Liusheng Duan
- State Key Laboratory of Plant Physiology and Biochemistry, Engineering Research Center of Plant Growth Regulator, Ministry of Education, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Mingcai Zhang
- State Key Laboratory of Plant Physiology and Biochemistry, Engineering Research Center of Plant Growth Regulator, Ministry of Education, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Weiming Tan
- State Key Laboratory of Plant Physiology and Biochemistry, Engineering Research Center of Plant Growth Regulator, Ministry of Education, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Dongyong Xu
- Hebei Provincial Engineering Research Center of Cotton Seed, Hejian, Hebei, China
| | - Zhaohu Li
- State Key Laboratory of Plant Physiology and Biochemistry, Engineering Research Center of Plant Growth Regulator, Ministry of Education, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
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Celton JM, Dheilly E, Guillou MC, Simonneau F, Juchaux M, Costes E, Laurens F, Renou JP. Additional amphivasal bundles in pedicel pith exacerbate central fruit dominance and induce self-thinning of lateral fruitlets in apple. PLANT PHYSIOLOGY 2014; 164:1930-51. [PMID: 24550240 PMCID: PMC3982754 DOI: 10.1104/pp.114.236117] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Apple (Malus × domestica) trees naturally produce an excess of fruitlets that negatively affect the commercial value of fruits brought to maturity and impact their capacity to develop flower buds the following season. Therefore, chemical thinning has become an important cultural practice, allowing the selective removal of unwanted fruitlets. As the public pressure to limit the use of chemical agents increases, the control of thinning becomes a major issue. Here, we characterized the self-thinning capacity of an apple hybrid genotype from the tree scale to the molecular level. Additional amphivasal vascular bundles were identified in the pith of pedicels supporting the fruitlets with the lowest abscission potential (central fruitlet), indicating that these bundles might have a role in the acquisition of dominance over lateral fruitlets. Sugar content analysis revealed that central fruitlets were better supplied in sorbitol than lateral fruitlets. Transcriptomic profiles allowed us to identify genes potentially involved in the overproduction of vascular tissues in central pedicels. In addition, histological and transcriptomic data permitted a detailed characterization of abscission zone development and the identification of key genes involved in this process. Our data confirm the major role of ethylene, auxin, and cell wall-remodeling enzymes in abscission zone formation. The shedding process in this hybrid appears to be triggered by a naturally exacerbated dominance of central fruitlets over lateral ones, brought about by an increased supply of sugars, possibly through additional amphivasal vascular bundles. The characterization of this genotype opens new perspectives for the selection of elite apple cultivars.
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Ultrastructural localization of polygalacturonase in ethylene-stimulated abscission of tomato pedicel explants. ScientificWorldJournal 2014; 2014:389896. [PMID: 24790564 PMCID: PMC3982476 DOI: 10.1155/2014/389896] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 02/19/2014] [Indexed: 11/18/2022] Open
Abstract
Polygalacturonase (PG) is crucial in plant organ abscission process. This paper investigated the cellular and subcellular localization of PG in ethylene-stimulated abscission of tomato pedicel explants. Confocal laser scanning microscopy of abscission zone sections with the fluorescent probe Cy3 revealed that PG was initially accumulated in parenchyma cells in cortical and vascular tissues after 8 h of ethylene treatment and then extended throughout the abscission zone when the abscission zone separated at 24 h after ethylene treatment. At the subcellular level, transmission electron microscopy with immunogold staining showed that PG showed abundant accumulation in the cortical and vascular tissues at 8 h after ethylene treatment, and the distribution area extended to the central parenchyma cells at 16 h after ethylene treatment. In addition, PGs were observed in the distal and proximal parts of the tomato pedicel explants throughout the abscission process. The results provided a visualized distribution of PG in the pedicel abscission zone and proved that PG was closely related to abscission.
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Kim J. Four shades of detachment: regulation of floral organ abscission. PLANT SIGNALING & BEHAVIOR 2014; 9:e976154. [PMID: 25482787 PMCID: PMC4623469 DOI: 10.4161/15592324.2014.976154] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 08/15/2014] [Accepted: 08/15/2014] [Indexed: 05/19/2023]
Abstract
Abscission of floral organs from the main body of a plant is a dynamic process that is developmentally and environmentally regulated. In the past decade, genetic studies in Arabidopsis have identified key signaling components and revealed their interactions in the regulation of floral organ abscission. The phytohormones jasmonic acid (JA) and ethylene play critical roles in flower development and floral organ abscission. These hormones regulate the timing of floral organ abscission both independently and inter-dependently. Although significant progress has been made in understanding abscission signaling, there are still many unanswered questions. These include considering abscission in the context of reproductive development and interplay between hormones embedded in the developmental processes. This review summarizes recent advances in the identification of molecular components in Arabidopsis and discusses their relationship with reproductive development. The emerging roles of hormones in the regulation of floral organ abscission, particularly by JA and ethylene, are examined.
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Key Words
- AGL15, AGAMOUS-LIKE 15
- AOS/DDE2, ALLENE OXIDE SYNTHASE/DELAYED DEHISCENCE 2
- ARF-GAP, ADP-ribosylation factor-GTPase activating protein
- AZ, abscission zone
- BOP1/2, BLADE ON PETIOLE 1/2
- BTP/POZ, Broad-Complex, Tramtrack, and Bric-a-brac/Pox virus and Zinc finger
- CST, CAST AWAY RECEPTOR-LIKE KINASE
- CTR1, CONSTITUTIVE TRIPLE RESPONSE 1
- DAB4/ COI1, DELAYED ABSCISSION 4/CORONATINE INSENSITIVE 1
- DAD1, DEFECTIVE ANTHER DEHISCENCE 1
- DDE1/OPR3, DELAYED DEHISCENCE 1/OXOPHYTODIENOATE-REDUCTASE 3
- EVR, EVERSHED RECEPTOR-LIKE KINASE
- EXP, EXPANSIN
- FAD7/8/3, FATTY ACID DESATURASE 7/8/3
- FYF, FOREVER YOUNG FLOWER
- HAE/HSL2, HAESA/HAESA-LIKE 2
- IM, inflorescence meristem
- JA, jasmonic acid
- JAZ, JASMONATE-ZIM DOMAIN
- KNAT1, KNOTTED-LIKE FROM ARABIDOPSIS THALIANA 1
- LOX3/4, LIPOXYGENASE 3/4
- LRR, leucine-rich repeat
- MAPK3/6, MAP Kinase 3/6
- MKK4/5, MAP Kinase Kinase 4/5
- NEV, NEVERSHED
- NPR1, NONEXPRESSOR OF PR GENES 1
- PG , POLYGALATURONASE
- PR1, Pathogenesis-related Protein 1
- SERK1, SOMATIC EMBRYO RECEPTOR-LIKE KIASE 1
- TCP4, TEOSINTE BRANCHED/CYCLOIDEA/PCF4
- XTH , XYLOGLUCAN ENDOTRANSGLUCOSYLASE/HYDROLASE
- ein2-1, ethylene insensitive 2-1
- ethylene
- etr1-1, ethylene response1-1
- floral organ abscission
- flower senescence
- ida, inflorescence deficient in abscission
- inflorescence meristem
- jasmonic acid
- reproductive development
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Affiliation(s)
- Joonyup Kim
- Soybean Genomics and Improvement Laboratory; Agricultural Research Service; USDA; Beltsville, MD USA
- Correspondence to: Joonyup Kim;
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Niederhuth CE, Cho SK, Seitz K, Walker JC. Letting go is never easy: abscission and receptor-like protein kinases. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2013; 55:1251-63. [PMID: 24138310 DOI: 10.1111/jipb.12116] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Accepted: 10/07/2013] [Indexed: 05/21/2023]
Abstract
Abscission is the process by which plants discard organs in response to environmental cues/stressors, or as part of their normal development. Abscission has been studied throughout the history of the plant sciences and in numerous species. Although long studied at the anatomical and physiological levels, abscission has only been elucidated at the molecular and genetic levels within the last two decades, primarily with the use of the model plant Arabidopsis thaliana. This has led to the discovery of numerous genes involved at all steps of abscission, including key pathways involving receptor-like protein kinases (RLKs). This review covers the current knowledge of abscission research, highlighting the role of RLKs. [Figure: see text] John C. Walker (Corresponding author).
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Affiliation(s)
- Chad E Niederhuth
- Department of Genetics, University of Georgia, Athens, Georgia, 30602, USA; Division of Biological Sciences, University of Missouri, Columbia, Missouri, 65211, USA; Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri, 65211, USA
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Qi X, Wu J, Wang L, Li L, Cao Y, Tian L, Dong X, Zhang S. Identifying the candidate genes involved in the calyx abscission process of 'Kuerlexiangli' (Pyrus sinkiangensis Yu) by digital transcript abundance measurements. BMC Genomics 2013; 14:727. [PMID: 24152304 PMCID: PMC4046677 DOI: 10.1186/1471-2164-14-727] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 10/18/2013] [Indexed: 11/25/2022] Open
Abstract
Background 'Kuerlexiangli’ (Pyrus sinkiangensis Yu), a native pear of Xinjiang, China, is an important agricultural fruit and primary export to the international market. However, fruit with persistent calyxes affect fruit shape and quality. Although several studies have looked into the physiological aspects of the calyx abscission process, the underlying molecular mechanisms remain unknown. In order to better understand the molecular basis of the process of calyx abscission, materials at three critical stages of regulation, with 6000 × Flusilazole plus 300 × PBO treatment (calyx abscising treatment) and 50 mg.L-1GA3 treatment (calyx persisting treatment), were collected and cDNA fragments were sequenced using digital transcript abundance measurements to identify candidate genes. Results Digital transcript abundance measurements was performed using high-throughput Illumina GAII sequencing on seven samples that were collected at three important stages of the calyx abscission process with chemical agent treatments promoting calyx abscission and persistence. Altogether more than 251,123,845 high quality reads were obtained with approximately 8.0 M raw data for each library. The values of 69.85%-71.90% of clean data in the digital transcript abundance measurements could be mapped to the pear genome database. There were 12,054 differentially expressed genes having Gene Ontology (GO) terms and associating with 251 Kyoto Encyclopedia of Genes and Genomes (KEGG) defined pathways. The differentially expressed genes correlated with calyx abscission were mainly involved in photosynthesis, plant hormone signal transduction, cell wall modification, transcriptional regulation, and carbohydrate metabolism. Furthermore, candidate calyx abscission-specific genes, e.g. Inflorescence deficient in abscission gene, were identified. Quantitative real-time PCR was used to confirm the digital transcript abundance measurements results. Conclusions We identified candidate genes that showed highly dynamic changes in expression during the calyx abscission process. These genes are potential targets for future functional characterization and should be valuable for exploration of the mechanisms of calyx abscission, and eventually for developing methods based on small molecule application to induce calyx abscission in fruit production. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-14-727) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Jun Wu
- College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China.
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Singh AP, Dubey S, Lakhwani D, Pandey SP, Khan K, Dwivedi UN, Nath P, Sane AP. Differential expression of several xyloglucan endotransglucosylase/hydrolase genes regulates flower opening and petal abscission in roses. AOB PLANTS 2013; 5:plt030. [PMCID: PMC4104646 DOI: 10.1093/aobpla/plt030] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2012] [Accepted: 07/01/2013] [Indexed: 05/25/2023]
Abstract
The movement of petals during flower opening (anthesis) and their separation from the parent plant during abscission requires cell wall modification at the junction (abscission zone) of the petal and thalamus. The present study shows differential ethylene mediated temporal regulation of various members of the rose XTH gene family during flower opening and abscission in the ethylene sensitive, early abscising fragrant rose and the less sensitive late abscising hybrid rose. These studies indicate that large scale changes in xyloglucan crosslinking in cell wall mediated by XTHs may facilitate movement and separation during flower opening and abscission respectively. Flower opening is a process that requires movement of petals from a closed position to a horizontal open position, while petal abscission requires cell-wall disassembly. Both processes are controlled by ethylene and require cell-wall modification at the junction (abscission zone) of the petal and thalamus to facilitate the movement or separation of petals. In the present study, a family of xyloglucan endotransglucosylase/hydrolase (XTH) genes was studied to understand their role in petal abscission in flowers of Rosa bourboniana (ethylene sensitive, early abscising) and Rosa hybrida (less ethylene sensitive, late abscising). Transcriptome sequencing of petal abscission zone cDNA was performed at different time points (ethylene treated and untreated) and screened for XTH genes. The study identified nine new XTH genes that showed differential changes in gene expression during flower opening and abscission. Of these, RbXTH3, RbXTH5, RbXTH6 and RbXTH12 were rapidly induced by ethylene within 1–4 h of ethylene treatment, corresponding to the period of flower opening. These genes also showed an early up-regulation during flower opening under ethylene-untreated (field abscission) conditions, indicating a possible role in anthesis and petal movement during flower opening. Other genes such as RbXTH4 and RbXTH9 were up-regulated later at 8–12 h after ethylene treatment and at 24–36 h under natural abscission conditions, indicating a possible role in abscission. Treatment with a higher ethylene dose (15 µL L−1 ethylene) accelerated abscission, leading to higher steady-state levels of XTH gene transcripts at an earlier time point compared with 0.5 µL L−1 ethylene. In contrast, transcript accumulation of most of the XTHs was considerably delayed in the late-abscising rose, R. hybrida, in keeping with the slower flower opening and delayed petal abscission. The results suggest coordinated action of different XTHs in cell-wall modification of xyloglucan moieties during flower opening as well as cell separation during abscission.
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Affiliation(s)
- Amar Pal Singh
- Plant Gene Expression Laboratory, Council of Scientific and Industrial Research – National Botanical Research Institute, Lucknow 226001, India
| | - Shveta Dubey
- Plant Gene Expression Laboratory, Council of Scientific and Industrial Research – National Botanical Research Institute, Lucknow 226001, India
| | | | - Saurabh Prakash Pandey
- Plant Gene Expression Laboratory, Council of Scientific and Industrial Research – National Botanical Research Institute, Lucknow 226001, India
| | - Kasim Khan
- Plant Gene Expression Laboratory, Council of Scientific and Industrial Research – National Botanical Research Institute, Lucknow 226001, India
| | | | - Pravendra Nath
- Plant Gene Expression Laboratory, Council of Scientific and Industrial Research – National Botanical Research Institute, Lucknow 226001, India
| | - Aniruddha P. Sane
- Plant Gene Expression Laboratory, Council of Scientific and Industrial Research – National Botanical Research Institute, Lucknow 226001, India
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Iwai H, Terao A, Satoh S. Changes in distribution of cell wall polysaccharides in floral and fruit abscission zones during fruit development in tomato (Solanum lycopersicum). JOURNAL OF PLANT RESEARCH 2013; 126:427-37. [PMID: 23124772 DOI: 10.1007/s10265-012-0536-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 10/10/2012] [Indexed: 05/20/2023]
Abstract
After fruit development has been triggered by pollination, the abscission zone (AZ) in the pedicel strengthens its adhesion to keep the fruit attached. Unpollinated flowers are shed at their respective AZs, whereas an enlargement of the same tissue is observed in pollinated flowers. After the fruit has developed and is fully ripened, shedding occurs easily at the AZ, indicating an acceleration of abscission. Cell wall degradation and synthesis may play important roles in these processes; however, little is understood. In this report, we have visualized changes in polysaccharide distribution in the AZs of pollinated versus unpollinated flowers and in the ripened fruits using immunohistochemistry. During floral abscission, a large increase was observed in LM15 labeling of xyloglucan specifically at the AZ in the abscising pedicel. LM5 and LM6 labeling of galactan and arabinan, respectively, also increased-LM5 throughout the pedicel and LM6 at the basal side of the AZ. The results suggest that xyloglucan, pectic galactan and arabinan play key roles in the abscission process. During fruit abscission, unlike in floral abscission, no AZ-specific cell wall polysaccharide deposition was observed; however, high autofluorescence was seen in the AZ of over-ripe fruit pedicels, suggesting secondary cell wall synthesis and lignification of the AZ prior to fruit abscission.
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Affiliation(s)
- Hiroaki Iwai
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan.
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Basu MM, González-Carranza ZH, Azam-Ali S, Tang S, Shahid AA, Roberts JA. The manipulation of auxin in the abscission zone cells of Arabidopsis flowers reveals that indoleacetic acid signaling is a prerequisite for organ shedding. PLANT PHYSIOLOGY 2013; 162:96-106. [PMID: 23509178 PMCID: PMC3641234 DOI: 10.1104/pp.113.216234] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 03/14/2013] [Indexed: 05/19/2023]
Abstract
A number of novel strategies were employed to examine the role of indoleacetic acid (IAA) in regulating floral organ abscission in Arabidopsis (Arabidopsis thaliana). Analysis of auxin influx facilitator expression in β-glucuronidase reporter plants revealed that AUXIN RESISTANT1, LIKE AUX1, and LAX3 were specifically up-regulated at the site of floral organ shedding. Flowers from mutants where individual family members were down-regulated exhibited a reduction in the force necessary to bring about petal separation; however, the effect was not additive in double or quadruple mutants. Using the promoter of a polygalacturonase (At2g41850), active primarily in cells undergoing separation, to drive expression of the bacterial genes iaaL and iaaM, we have shown that it is possible to manipulate auxin activity specifically within the floral organ abscission zone (AZ). Analysis of petal breakstrength reveals that if IAA AZ levels are reduced, shedding takes place prematurely, while if they are enhanced, organ loss is delayed. The At2g41850 promoter was also used to transactivate the gain-of-function AXR3-1 gene in order to disrupt auxin signaling specifically within the floral organ AZ cells. Flowers from transactivated lines failed to shed their sepals, petals, and anthers during pod expansion and maturity, and these organs frequently remained attached to the plant even after silique desiccation and dehiscence had taken place. These observations support a key role for IAA in the regulation of abscission in planta and reveal, to our knowledge for the first time, a requirement for a functional IAA signaling pathway in AZ cells for organ shedding to take place.
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Estornell LH, Agustí J, Merelo P, Talón M, Tadeo FR. Elucidating mechanisms underlying organ abscission. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2013; 199-200:48-60. [PMID: 23265318 DOI: 10.1016/j.plantsci.2012.10.008] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 10/03/2012] [Accepted: 10/31/2012] [Indexed: 05/19/2023]
Abstract
Abscission consists in the detachment of entire vegetative and reproductive organs due to cell separation processes occurring at the abscission zones (AZs) at specific positions of the plant body. From an evolutionary point of view, abscission is a highly advantageous process resulting into fruit and seed dispersal as well as the shedding of no longer useful organs. In an agricultural context, however, abscission may become a major limiting factor for crop productivity. Domestication of major crops included the selection of plants that did not naturally shed ripe fruits or seeds. The understanding of abscission is of great importance to control seed and fruit production and to improve breeding and harvesting practices. Thus, advances made on model plants and crops are of major importance since they may provide potential candidate genes for further biotechnological applications. Here, we review the current knowledge of the physiological, genetic and genomic aspects related to abscission including the most recently disclosed putative regulators that appear to be implicated in the development and/or activation of the AZs.
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Affiliation(s)
- Leandro H Estornell
- Institut Valencià d'Investigacions Agràries (IVIA), Centre de Genómica, Apartat Oficial, Montcada (València), Spain
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Niederhuth CE, Patharkar OR, Walker JC. Transcriptional profiling of the Arabidopsis abscission mutant hae hsl2 by RNA-Seq. BMC Genomics 2013; 14:37. [PMID: 23327667 PMCID: PMC3566969 DOI: 10.1186/1471-2164-14-37] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Accepted: 01/14/2013] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Abscission is a mechanism by which plants shed entire organs in response to both developmental and environmental signals. Arabidopsis thaliana, in which only the floral organs abscise, has been used extensively to study the genetic, molecular and cellular processes controlling abscission. Abscission in Arabidopsis requires two genes that encode functionally redundant receptor-like protein kinases, HAESA (HAE) and HAESA-LIKE 2 (HSL2). Double hae hsl2 mutant plants fail to abscise their floral organs at any stage of floral development and maturation. RESULTS Using RNA-Seq, we compare the transcriptomes of wild-type and hae hsl2 stage 15 flowers, using the floral receptacle which is enriched for abscission zone cells. 2034 genes were differentially expressed with a False Discovery Rate adjusted p < 0.05, of which 349 had two fold or greater change in expression. Differentially expressed genes were enriched for hydrolytic, cell wall modifying, and defense related genes. Testing several of the differentially expressed genes in INFLORESCENCE DEFICIENT IN ABSCISSION (ida) mutants shows that many of the same genes are co-regulated by IDA and HAE HSL2 and support the role of IDA in the HAE and HSL2 signaling pathway. Comparison to microarray data from stamen abscission zones show distinct patterns of expression of genes that are dependent on HAE HSL2 and reveal HAE HSL2- independent pathways. CONCLUSION HAE HSL2-dependent and HAE HSL2-independent changes in genes expression are required for abscission. HAE and HSL2 affect the expression of cell wall modifying and defense related genes necessary for abscission. The HAE HSL2-independent genes also appear to have roles in abscission and additionally are involved in processes such as hormonal signaling, senescence and callose deposition.
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Affiliation(s)
- Chad E Niederhuth
- Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri 65211, USA
| | - O Rahul Patharkar
- Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri 65211, USA
| | - John C Walker
- Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211, USA
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri 65211, USA
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Liljegren SJ. Organ abscission: exit strategies require signals and moving traffic. CURRENT OPINION IN PLANT BIOLOGY 2012; 15:670-6. [PMID: 23047135 DOI: 10.1016/j.pbi.2012.09.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2012] [Revised: 09/13/2012] [Accepted: 09/13/2012] [Indexed: 05/18/2023]
Abstract
Flowers are frequently programmed to release their outer organs after pollination. Managing the timing and extent of cell separation during abscission is crucial, as premature shedding could interfere with reproduction and the structural integrity of neighboring tissues would be affected by uninhibited loss of cellular adhesion. In Arabidopsis flowers, the framework of the cell signaling, membrane traffic and transcriptional networks responsible for organ abscission is now emerging. A proposed ligand-receptor system consisting of a secreted peptide and a pair of redundant receptor-like kinases switches on a mitogen-activated protein kinase cascade that leads to cell separation. A homeodomain transcription factor acting downstream of the ligand-receptor module may inhibit cell expansion and separation by restricting the expression of other closely related transcription factors. Three additional receptor-like kinases may inhibit abscission by reducing the pool of receptors at the cell surface available to be ligand-activated. A G-protein regulator is required to direct the movement of key molecules required for abscission. Expression of a polygalaturonase active during organ abscission is modulated by a zinc finger transcription factor.
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Affiliation(s)
- Sarah J Liljegren
- Department of Biology, University of Mississippi, Oxford, MS 38677-1848, USA.
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Yan M, Zhang Y, Guo W, Wang X. Soybean endo-β-mannanase GmMAN1 is not associated with leaf abscission, but might be involved in the response to wounding. PLoS One 2012; 7:e49197. [PMID: 23173047 PMCID: PMC3500276 DOI: 10.1371/journal.pone.0049197] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 10/08/2012] [Indexed: 11/18/2022] Open
Abstract
The objective of this work is to investigate the relationship between endo-β-mannanase and leaf abscission, and response to wounding in soybean (Glycine max). An endo-β-mannanase gene GmMAN1 was cloned from the abscission zone in petiole explants, and was heterologously expressed in E. coli. Polyclonal antibodies were raised against the fusion protein. The increases in activity, isoform numbers, and amounts of transcripts and proteins of GmMAN1 were found not only in the abscission zone but also in the non-abscission zone during petiole abscission in the explants, but not in these two tissues during leaf abscission artificially induced by ethephon treatment in the intact plants. The changes in endo-β-mannanase expression patterns in these two tissues were probably induced by the inherent mechanical wounding during the preparation of explants. When soybean plants were wounded by removing half of the leaf blade of the first pair of true leaves, the transcripts and proteins of GmMAN1 were induced in the leaves and stem, leading to the increases in enzyme activity and isoform numbers in them. It is concluded that the soybean endo-β-mannanase GmMAN1 is not associated with leaf abscission, but might be involved in the response to wounding.
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Affiliation(s)
- Min Yan
- College of Life Sciences, South China Agricultural University, Guangzhou, People’s Republic of China
| | - Yifan Zhang
- College of Life Sciences, South China Agricultural University, Guangzhou, People’s Republic of China
| | - Wenjuan Guo
- College of Life Sciences, South China Agricultural University, Guangzhou, People’s Republic of China
| | - Xiaofeng Wang
- College of Life Sciences, South China Agricultural University, Guangzhou, People’s Republic of China
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González-Carranza ZH, Shahid AA, Zhang L, Liu Y, Ninsuwan U, Roberts JA. A novel approach to dissect the abscission process in Arabidopsis. PLANT PHYSIOLOGY 2012; 160:1342-56. [PMID: 22992509 PMCID: PMC3490599 DOI: 10.1104/pp.112.205955] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 09/16/2012] [Indexed: 05/20/2023]
Abstract
Abscission is the consequence of a specialized layer of cells undergoing a complex series of molecular and biochemical events. Analysis of the specific molecular changes associated with abscission is hampered by contamination from neighboring nonseparating tissues. Moreover, studies of abscission frequently involve the examination of events that take place in isolated segments of tissue exposed to nonphysiological concentrations of ethylene or indole-3-acetic acid for protracted periods (more than 24 h) of time. To resolve these problems, we have adopted the use of a transgenic line of Arabidopsis (Arabidopsis thaliana) where the promoter of an abscission-specific polygalacturonase gene (At2g41850/ARABIDOPSIS DEHISCENCE ZONE POLYGALACTURONASE2) has been fused to a green fluorescent protein reporter. RNA was extracted from green fluorescent protein-tagged cells, released from abscising floral organs, and used to generate a complementary DNA library. This library was used to probe a microarray, and a population of abscission-related transcripts was studied in detail. Seven novel abscission-related genes were identified, four of which encode proteins of unknown function. Reverse transcription-polymerase chain reaction analyses and promoter fusions to the β-glucuronidase reporter gene confirmed the expression of these genes in the abscission zone and revealed other places of expression during seedling development. Three of these genes were studied further by crossing reporter lines to the abscission mutants inflorescence deficient in abscission (ida) and blade-on-petiole1 (bop1)/bop2 and an IDA-overexpressing line. Phenotypic analysis of an At3g14380 transfer DNA insertion line indicates that this gene plays a functional role in floral organ shedding. This strategy has enabled us to uncover new genes involved in abscission, and their possible contribution to the process is discussed.
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Affiliation(s)
- Zinnia Haydee González-Carranza
- Plant and Crop Sciences Division, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, United Kingdom.
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Roongsattham P, Morcillo F, Jantasuriyarat C, Pizot M, Moussu S, Jayaweera D, Collin M, Gonzalez-Carranza ZH, Amblard P, Tregear JW, Tragoonrung S, Verdeil JL, Tranbarger TJ. Temporal and spatial expression of polygalacturonase gene family members reveals divergent regulation during fleshy fruit ripening and abscission in the monocot species oil palm. BMC PLANT BIOLOGY 2012; 12:150. [PMID: 22920238 PMCID: PMC3546427 DOI: 10.1186/1471-2229-12-150] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 07/26/2012] [Indexed: 05/18/2023]
Abstract
BACKGROUND Cell separation that occurs during fleshy fruit abscission and dry fruit dehiscence facilitates seed dispersal, the final stage of plant reproductive development. While our understanding of the evolutionary context of cell separation is limited mainly to the eudicot model systems tomato and Arabidopsis, less is known about the mechanisms underlying fruit abscission in crop species, monocots in particular. The polygalacturonase (PG) multigene family encodes enzymes involved in the depolymerisation of pectin homogalacturonan within the primary cell wall and middle lamella. PG activity is commonly found in the separation layers during organ abscission and dehiscence, however, little is known about how this gene family has diverged since the separation of monocot and eudicots and the consequence of this divergence on the abscission process. RESULTS The objective of the current study was to identify PGs responsible for the high activity previously observed in the abscission zone (AZ) during fruit shedding of the tropical monocot oil palm, and to analyze PG gene expression during oil palm fruit ripening and abscission. We identified 14 transcripts that encode PGs, all of which are expressed in the base of the oil palm fruit. The accumulation of five PG transcripts increase, four decrease and five do not change during ethylene treatments that induce cell separation. One PG transcript (EgPG4) is the most highly induced in the fruit base, with a 700-5000 fold increase during the ethylene treatment. In situ hybridization experiments indicate that the EgPG4 transcript increases preferentially in the AZ cell layers in the base of the fruit in response to ethylene prior to cell separation. CONCLUSIONS The expression pattern of EgPG4 is consistent with the temporal and spatial requirements for cell separation to occur during oil palm fruit shedding. The sequence diversity of PGs and the complexity of their expression in the oil palm fruit tissues contrast with data from tomato, suggesting functional divergence underlying the ripening and abscission processes has occurred between these two fruit species. Furthermore, phylogenetic analysis of EgPG4 with PGs from other species suggests some conservation, but also diversification has occurred between monocots and eudicots, in particular between dry and fleshy fruit species.
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Affiliation(s)
- Peerapat Roongsattham
- Institut de Recherche pour le Développement, IRD Centre de Montpellier, IRD/CIRAD Palm Development Group, DIADE 911 avenue agropolis BP 64501, 34394, Montpellier cedex 5, France
| | - Fabienne Morcillo
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement, CIRAD, UMR DIADE, Montpellier, F-34398, France
| | - Chatchawan Jantasuriyarat
- Department of Genetics, Faculty of Science, Kasetsart University, Bangkhen Campus, 50 Phahonyothin Road, Jatujak, Thailand
| | - Maxime Pizot
- Institut de Recherche pour le Développement, IRD Centre de Montpellier, IRD/CIRAD Palm Development Group, DIADE 911 avenue agropolis BP 64501, 34394, Montpellier cedex 5, France
| | - Steven Moussu
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement, CIRAD, UMR DIADE, Montpellier, F-34398, France
| | - Dasuni Jayaweera
- Division, Loughborough, The University of Nottingham, Sutton Bonington Campus, School of Biosciences, Plant Science, Leicestershire, LE12 5RD, United Kingdom
| | - Myriam Collin
- Institut de Recherche pour le Développement, IRD Centre de Montpellier, IRD/CIRAD Palm Development Group, DIADE 911 avenue agropolis BP 64501, 34394, Montpellier cedex 5, France
| | - Zinnia H Gonzalez-Carranza
- Division, Loughborough, The University of Nottingham, Sutton Bonington Campus, School of Biosciences, Plant Science, Leicestershire, LE12 5RD, United Kingdom
| | | | - James W Tregear
- Institut de Recherche pour le Développement, IRD Centre de Montpellier, IRD/CIRAD Palm Development Group, DIADE 911 avenue agropolis BP 64501, 34394, Montpellier cedex 5, France
| | - Somvong Tragoonrung
- Genome Institute, National Center for Genetic Engineering and Biotechnology, BIOTEC, 113 Thailand Science Park, Phahonyothin Road, Klong 1, Klong Luang, Pathumthani, 12120, Thailand
| | - Jean-Luc Verdeil
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement CIRAD, UMR AGAP, MRI-PHIV, Montpellier, F-34398, France
| | - Timothy J Tranbarger
- Institut de Recherche pour le Développement, IRD Centre de Montpellier, IRD/CIRAD Palm Development Group, DIADE 911 avenue agropolis BP 64501, 34394, Montpellier cedex 5, France
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Bar-Dror T, Dermastia M, Kladnik A, Žnidarič MT, Novak MP, Meir S, Burd S, Philosoph-Hadas S, Ori N, Sonego L, Dickman MB, Lers A. Programmed cell death occurs asymmetrically during abscission in tomato. THE PLANT CELL 2011; 23:4146-63. [PMID: 22128123 PMCID: PMC3246325 DOI: 10.1105/tpc.111.092494] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Revised: 10/11/2011] [Accepted: 11/17/2011] [Indexed: 05/03/2023]
Abstract
Abscission occurs specifically in the abscission zone (AZ) tissue as a natural stage of plant development. Previously, we observed delay of tomato (Solanum lycopersicum) leaf abscission when the LX ribonuclease (LX) was inhibited. The known association between LX expression and programmed cell death (PCD) suggested involvement of PCD in abscission. In this study, hallmarks of PCD were identified in the tomato leaf and flower AZs during the late stage of abscission. These included loss of cell viability, altered nuclear morphology, DNA fragmentation, elevated levels of reactive oxygen species and enzymatic activities, and expression of PCD-associated genes. Overexpression of antiapoptotic proteins resulted in retarded abscission, indicating PCD requirement. PCD, LX, and nuclease gene expression were visualized primarily in the AZ distal tissue, demonstrating an asymmetry between the two AZ sides. Asymmetric expression was observed for genes associated with cell wall hydrolysis, leading to AZ, or associated with ethylene biosynthesis, which induces abscission. These results suggest that different abscission-related processes occur asymmetrically between the AZ proximal and distal sides. Taken together, our findings identify PCD as a key mechanism that occurs asymmetrically during normal progression of abscission and suggest an important role for LX in this PCD process.
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Affiliation(s)
- Tal Bar-Dror
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Marina Dermastia
- Department of Biotechnology and Systems Biology, National Institute of Biology, SI-1000 Ljubljana, Slovenia
| | - Aleš Kladnik
- Department of Biology, Biotechnical Faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - Magda Tušek Žnidarič
- Department of Biotechnology and Systems Biology, National Institute of Biology, SI-1000 Ljubljana, Slovenia
| | - Maruša Pompe Novak
- Department of Biotechnology and Systems Biology, National Institute of Biology, SI-1000 Ljubljana, Slovenia
| | - Shimon Meir
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel
| | - Shaul Burd
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel
| | - Sonia Philosoph-Hadas
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel
| | - Naomi Ori
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Lilian Sonego
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel
| | - Martin B. Dickman
- Department of Plant Pathology and Microbiology, Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, Texas 77843
| | - Amnon Lers
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel
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Singh AP, Tripathi SK, Nath P, Sane AP. Petal abscission in rose is associated with the differential expression of two ethylene-responsive xyloglucan endotransglucosylase/hydrolase genes, RbXTH1 and RbXTH2. JOURNAL OF EXPERIMENTAL BOTANY 2011; 62:5091-103. [PMID: 21765161 PMCID: PMC3193013 DOI: 10.1093/jxb/err209] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Abscission is a process that involves shedding of plant organs from the main plant body. In this study it is shown that the process of petal separation in the fragrant rose, Rosa bourboniana, is accompanied by the expression of two xyloglucan endotransglucosylase/hydrolase genes, RbXTH1 and RbXTH2. The sequences of the two genes show 52% amino acid identity but are conserved at the catalytic site. The genes are up-regulated soon after the initiation of the abscission process and their transcription is associated with the progression of abscission, being faster in ethylene-treated flowers but slower during field abscission. Transcription is ethylene responsive, with the ethylene response being tissue-specific for RbXTH1 but largely tissue-independent for RbXTH2. Expression is correlated with an increase in xyloglucan endotransglucosylase (XET) action in petal abscission zones of both ethylene-treated and field abscising flowers. Proximal promoters of both the genes drive β-glucuronidase expression in an ethylene-responsive and abscission-related manner in agrobacteria-infiltrated rose petals, indicating that cis-elements governing ethylene-responsive and abscission-related expression probably lie within the first 700 nucleotides upstream of the translational initiation codon. The results show that cell wall remodelling of the xyloglucan moieties through the XET action of XTHs may be important for cell separation during abscission.
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49
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Bowling AJ, Vaughn KC. Leaf abscission in Impatiens (Balsaminaceae) is due to loss of highly de-esterified homogalacturonans in the middle lamellae. AMERICAN JOURNAL OF BOTANY 2011; 98:619-29. [PMID: 21613162 DOI: 10.3732/ajb.1000268] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
PREMISE OF STUDY Abscission zones (AZ) are sites where leaves and other organs are shed. Investigating the AZ by classical biochemical techniques is difficult due to its small size and because the surrounding tissue is not involved in abscission. The goals of this study were to determine whether AZ cell walls are chemically unique from the other cells of the petiole, perhaps making them more susceptible to enzymatic degradation during abscission and to identify which cell wall polysaccharides are degraded during abscission. METHODS A battery of antibodies that recognize a large number of cell wall polysaccharide and glycoprotein epitopes was used to probe sections of the Impatiens leaf AZ at several time points in the abscission process. KEY RESULTS Prior to abscission, the walls of the AZ cells were found to be similar in composition to the walls of the cells both proximal and distal to the AZ. Of all the epitopes monitored, only the highly de-esterified homogalacturonans (HG) of the middle lamellae were found to be reduced post-abscission and only at the plane of separation. More highly esterified homogalacturonans, as well as other pectin and xyloglucan epitopes were not affected. Furthermore, cellulose, as detected by an endoglucanase-gold probe and cellulose-binding module staining, was unaffected, even on the walls of the cells facing the separation site. CONCLUSIONS In the leaf abscission zone of Impatiens, wall alterations during abscission are strictly limited to the plane of separation and involve only the loss of highly de-esterified pectins from the middle lamellae.
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Affiliation(s)
- Andrew J Bowling
- Southern Weed Science Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Stoneville, Mississippi 38776, USA.
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50
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Newman SM, Tantasawat P, Steffens JC. Tomato polyphenol oxidase B is spatially and temporally regulated during development and in response to ethylene. Molecules 2011; 16:493-517. [PMID: 21224781 PMCID: PMC6259212 DOI: 10.3390/molecules16010493] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 01/07/2011] [Indexed: 01/14/2023] Open
Abstract
Plant polyphenol oxidases (PPOs) are ubiquitous plastid-localized enzymes. A precise analysis of PPO function in plants has been complicated by the presence of several family members with immunological cross reactivity. Previously we reported the isolation of genomic clones coding for the seven members of the tomato (Solanum lycopersicum) PPO family (A, A', B, C, D, E, and F). Here we report the complex spatial and temporal expression of one of the members, PPO B. The PPO B promoter was sequenced and subjected to homology analysis. Sequence similarities were found to nucleotide sequences of genes encoding enzymes/proteins active in the following systems: phenylpropanoid biosynthesis, signal transduction and responsiveness to hormones and stresses, fruit and seed proteins/enzymes, and photosynthesis. Chimeric gene fusions were constructed linking PPO B 5' flanking regions to the reporter gene, b-glucuronidase (GUS). The resultant transgenic plants were histochemically analyzed for GUS activity in various vegetative and reproductive tissues, and evaluated for PPO B responsiveness to ethylene induction. It was shown that PPO B expression was tissue specific, developmentally regulated, ethylene induced, and localized predominantly to mitotic or apoptotic tissues.
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Affiliation(s)
- Sally M. Newman
- Department of Plant Breeding and Genetics, 252 Emerson Hall, Cornell University, Ithaca, NY 14853, USA
| | - Piyada Tantasawat
- Department of Plant Breeding and Genetics, 252 Emerson Hall, Cornell University, Ithaca, NY 14853, USA
- Suranaree University of Technology, 111 University Ave., Muang District, Nakhon Ratchasima 30000, Thailand
| | - John C. Steffens
- Department of Plant Breeding and Genetics, 252 Emerson Hall, Cornell University, Ithaca, NY 14853, USA
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