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Schilbert HM, Holzenkamp K, Viehöver P, Holtgräwe D, Möllers C. Homoeologous non-reciprocal translocation explains a major QTL for seed lignin content in oilseed rape (Brassica napus L.). TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2023; 136:172. [PMID: 37439815 PMCID: PMC10345078 DOI: 10.1007/s00122-023-04407-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 06/22/2023] [Indexed: 07/14/2023]
Abstract
A homoeologous non-reciprocal translocation was identified in the major QTL for seed lignin content in the low lignin line SGDH14. The lignin biosynthetic gene PAL4 was deleted. Oilseed rape is a major oil crop and a valuable protein source for animal and human nutrition. Lignin is a non-digestible, major component of the seed coat with negative effect on sensory quality, bioavailability and usage of oilseed rape's protein. Hence, seed lignin reduction is of economic and nutritional importance. In this study, the major QTL for reduced lignin content found on chromosome C05 in the DH population SGDH14 x Express 617 was further examined. SGDH14 had lower seed lignin content than Express 617. Harvested seeds from a F2 population of the same cross were additionally field tested and used for seed quality analysis. The F2 population showed a bimodal distribution for seed lignin content. F2 plants with low lignin content had thinner seed coats compared to high lignin lines. Both groups showed a dark seed colour with a slightly lighter colour in the low lignin group indicating that a low lignin content is not necessarily associated with yellow seed colour. Mapping of genomic long-reads from SGDH14 against the Express 617 genome assembly revealed a homoeologous non-reciprocal translocation (HNRT) in the confidence interval of the major QTL for lignin content. A homologous A05 region is duplicated and replaced the C05 region in SGDH14. As consequence several genes located in the C05 region were lost in SGDH14. Thus, a HNRT was identified in the major QTL region for reduced lignin content in the low lignin line SGDH14. The most promising candidate gene related to lignin biosynthesis on C05, PAL4, was deleted.
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Affiliation(s)
- Hanna Marie Schilbert
- Genetics and Genomics of Plants, CeBiTec and Faculty of Biology, Bielefeld University, Bielefeld, Germany.
- Graduate School DILS, Bielefeld Institute for Bioinformatics Infrastructure (BIBI), Faculty of Technology, Bielefeld University, Bielefeld, Germany.
| | - Karin Holzenkamp
- Department of Crop Sciences, Division of Crop Plant Genetics, Georg-August-University, Göttingen, Germany
| | - Prisca Viehöver
- Genetics and Genomics of Plants, CeBiTec and Faculty of Biology, Bielefeld University, Bielefeld, Germany
| | - Daniela Holtgräwe
- Genetics and Genomics of Plants, CeBiTec and Faculty of Biology, Bielefeld University, Bielefeld, Germany
| | - Christian Möllers
- Department of Crop Sciences, Division of Crop Plant Genetics, Georg-August-University, Göttingen, Germany
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2
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Zhang Y, Zhang H, Zhao H, Xia Y, Zheng X, Fan R, Tan Z, Duan C, Fu Y, Li L, Ye J, Tang S, Hu H, Xie W, Yao X, Guo L. Multi-omics analysis dissects the genetic architecture of seed coat content in Brassica napus. Genome Biol 2022; 23:86. [PMID: 35346318 PMCID: PMC8962237 DOI: 10.1186/s13059-022-02647-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 03/07/2022] [Indexed: 01/01/2023] Open
Abstract
Background Brassica napus is an important vegetable oil source worldwide. Seed coat content is a complex quantitative trait that negatively correlates with the seed oil content in B. napus. Results Here we provide insights into the genetic basis of natural variation of seed coat content by transcriptome-wide association studies (TWAS) and genome-wide association studies (GWAS) using 382 B. napus accessions. By population transcriptomic analysis, we identify more than 700 genes and four gene modules that are significantly associated with seed coat content. We also characterize three reliable quantitative trait loci (QTLs) controlling seed coat content by GWAS. Combining TWAS and correlation networks of seed coat content-related gene modules, we find that BnaC07.CCR-LIKE (CCRL) and BnaTT8s play key roles in the determination of the trait by modulating lignin biosynthesis. By expression GWAS analysis, we identify a regulatory hotspot on chromosome A09, which is involved in controlling seed coat content through BnaC07.CCRL and BnaTT8s. We then predict the downstream genes regulated by BnaTT8s using multi-omics datasets. We further experimentally validate that BnaCCRL and BnaTT8 positively regulate seed coat content and lignin content. BnaCCRL represents a novel identified gene involved in seed coat development. Furthermore, we also predict the key genes regulating carbon allocation between phenylpropane compounds and oil during seed development in B. napus. Conclusions This study helps us to better understand the complex machinery of seed coat development and provides a genetic resource for genetic improvement of seed coat content in B. napus breeding. Supplementary Information The online version contains supplementary material available at 10.1186/s13059-022-02647-5.
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Jayawardhane KN, Singer SD, Ozga JA, Rizvi SM, Weselake RJ, Chen G. Seed-specific down-regulation of Arabidopsis CELLULOSE SYNTHASE 1 or 9 reduces seed cellulose content and differentially affects carbon partitioning. PLANT CELL REPORTS 2020; 39:953-969. [PMID: 32314045 DOI: 10.1007/s00299-020-02541-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Accepted: 04/04/2020] [Indexed: 06/11/2023]
Abstract
Seed-specific down-regulation of AtCESA1 and AtCESA9, which encode cellulose synthase subunits, differentially affects seed storage compound accumulation in Arabidopsis. High amounts of cellulose can negatively affect crop seed quality, and, therefore, diverting carbon partitioning from cellulose to oil, protein and/or starch via molecular breeding may improve seed quality. To determine the effect of seed cellulose content reduction on levels of storage compounds, Arabidopsis thaliana CELLULOSE SYNTHASE1 (AtCESA1) and AtCESA9 genes, which both encode cellulose synthase subunits, were individually down-regulated using seed-specific intron-spliced hairpin RNA (hpRNAi) constructs. The selected seed-specific AtCESA1 and AtCESA9 Arabidopsis RNAi lines displayed reduced cellulose contents in seeds, and exhibited no obvious visual phenotypic growth defects with the exception of a minor effect on early root development in AtCESA1 RNAi seedlings and early hypocotyl elongation in the dark in both types of RNAi line. The seed-specific down-regulation of AtCESA9 resulted in a reduction in seed weight compared to empty vector controls, which was not observed in AtCESA1 RNAi lines. In terms of effects on carbon partitioning, AtCESA1 and AtCESA9 RNAi lines exhibited distinct effects. The down-regulation of AtCESA1 led to a ~ 3% relative increase in seed protein content (P = 0.04) and a ~ 3% relative decrease in oil content (P = 0.02), but caused no alteration in soluble glucose levels. On the contrary, AtCESA9 RNAi lines did not display a significant reduction in seed oil, protein or soluble glucose content. Taken together, our results indicate that the seed-specific down-regulation of AtCESA1 causes alterations in seed storage compound accumulation, while the effect of AtCESA9 on carbon partitioning is absent or minor in Arabidopsis.
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Affiliation(s)
- Kethmi N Jayawardhane
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada
| | - Stacy D Singer
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, T1J 4B1, Canada
| | - Jocelyn A Ozga
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada
| | - Syed Masood Rizvi
- Corteva Agriscience, Site 600, RR #6, PO Box 12, Saskatoon, SK, S7K 3J9, Canada
| | - Randall J Weselake
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada
| | - Guanqun Chen
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada.
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Tang M, Tong C, Liang L, Du C, Zhao J, Xiao L, Tong J, Dai X, Helal M, Dai W, Xiang Y. A recessive high-density pod mutant resource of Brassica napus. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 293:110411. [PMID: 32081260 DOI: 10.1016/j.plantsci.2020.110411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 01/06/2020] [Accepted: 01/07/2020] [Indexed: 05/28/2023]
Abstract
In Brassica napus, pod number and pod density are critical factors to determine seed yield. Although the pod density is an essential yield trait, the regulation of yield formation in oil crops, as well as the genetic and molecular mechanisms, are poorly understood. In this study, we characterized a rapeseed high-density pod mutant (dpt247) from composite hybridization. To shed some light on the nature of this mutation, it was investigated morphologically, anatomically, physiologically, genetically and transcriptomically. The mutant plant showed noticeable phenotypic differences in comparison with the control plant, including reduced plant height and primary branch length, decreased number of primary branches, significantly increased number of pod on the main inflorescence, and more compact pod distribution. Besides, the mutant had higher levels of indole-3-acetic acid (IAA) and zeatin riboside (ZR) in the shoot apical meristem (SAM). The dense pod trait was controlled by two major recessive genes identified in the segregating genetic populations of GRE501 and dpt247. RNA sequencing indicated genes participated in auxin, cytokinin and WUS/CLV signalling pathway in dpt247 were more active in the mutant. These results provide important information for understanding the regulation of yield formation and high yield breeding in rapeseed.
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Affiliation(s)
- Minqiang Tang
- Guizhou Rapeseed Institute, Guizhou Academy of Agricultural Sciences, Guiyang 550008, PR China; Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, PR China
| | - Chaobo Tong
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, PR China
| | - Longbin Liang
- Guizhou Rapeseed Institute, Guizhou Academy of Agricultural Sciences, Guiyang 550008, PR China
| | - Caifu Du
- Guizhou Rapeseed Institute, Guizhou Academy of Agricultural Sciences, Guiyang 550008, PR China
| | - Jixian Zhao
- Guizhou Rapeseed Institute, Guizhou Academy of Agricultural Sciences, Guiyang 550008, PR China
| | - Langtao Xiao
- Hunan Provincial Key Laboratory of Phytohormones and Growth and Development, Hunan Agricultural University, Changsha 410128, PR China
| | - Jianhua Tong
- Hunan Provincial Key Laboratory of Phytohormones and Growth and Development, Hunan Agricultural University, Changsha 410128, PR China
| | - Xianglai Dai
- Guizhou Rapeseed Institute, Guizhou Academy of Agricultural Sciences, Guiyang 550008, PR China
| | - Mmu Helal
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, PR China
| | - Wendong Dai
- Guizhou Rapeseed Institute, Guizhou Academy of Agricultural Sciences, Guiyang 550008, PR China
| | - Yang Xiang
- Guizhou Rapeseed Institute, Guizhou Academy of Agricultural Sciences, Guiyang 550008, PR China.
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Francoz E, Lepiniec L, North HM. Seed coats as an alternative molecular factory: thinking outside the box. PLANT REPRODUCTION 2018; 31:327-342. [PMID: 30056618 DOI: 10.1007/s00497-018-0345-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 07/13/2018] [Indexed: 05/15/2023]
Abstract
Seed coats as commodities. Seed coats play important roles in the protection of the embryo from biological attack and physical damage by the environment as well as dispersion strategies. A significant part of the energy devoted by the mother plant to seed production is channeled into the production of the cell layers and metabolites that surround the embryo. Nevertheless, in crop species these are often discarded post-harvest and are a wasted resource that could be processed to yield co-products. The production of novel compounds from existing metabolites is also a possibility. A number of macromolecules are already accumulated in these maternal layers that could be exploited in industrial applications either directly or via green chemistry, notably flavonoids, lignin, lignan, polysaccharides, lipid polyesters and waxes. Here, we summarize our knowledge of the in planta biosynthesis pathways of these macromolecules and their molecular regulation as well as potential applications. We also outline recent work aimed at providing further tools for increasing yields of existing molecules or the development of novel biotech approaches, as well as trial studies aimed at exploiting this underused resource.
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Affiliation(s)
- Edith Francoz
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Loïc Lepiniec
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Helen M North
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France.
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Ye J, Yang Y, Chen B, Shi J, Luo M, Zhan J, Wang X, Liu G, Wang H. An integrated analysis of QTL mapping and RNA sequencing provides further insights and promising candidates for pod number variation in rapeseed (Brassica napus L.). BMC Genomics 2017; 18:71. [PMID: 28077071 PMCID: PMC5225578 DOI: 10.1186/s12864-016-3402-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 12/09/2016] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND As the most important yield component in rapeseed (Brassica napus L.), pod number is determined by a series of successive growth and development processes. Pod number shows extensive variation in rapeseed natural germplasm, which is valuable for genetic improvement. However, the genetic and especially the molecular mechanism for this kind of variation are poorly understood. In this study, we conducted QTL mapping and RNA sequencing, respectively, using the BnaZNRIL population and its two parental cultivars Zhongshuang11 and No.73290 which showed significant difference in pod number, primarily due to the difference in floral organ number. RESULT A total of eight QTLs for pod number were identified using BnaZNRIL population with a high-density SNP linkage map, each was distributed on seven linkage groups and explained 5.8-11.9% of phenotypic variance. Then, they were integrated with those previously detected in BnaZNF2 population (deriving from same parents) and resulted in 15 consensus-QTLs. Of which, seven QTLs were identical to other studies, whereas the other eight should be novel. RNA sequencing of the shoot apical meristem (SAM) at the formation stage of floral bud primordia identified 9135 genes that were differentially expressed between the two parents. Gene ontology (GO) analysis showed that the top two enriched groups were S-assimilation, providing an essential nutrient for the synthesis of diverse metabolites, and polyamine metabolism, serving as second messengers that play an essential role in flowering genes initiation. KEGG analysis showed that the top three overrepresented pathways were carbohydrate (707 genes), amino acid (390 genes) and lipid metabolisms (322 genes). In silico mapping showed that 647 DEGs were located within the confidence intervals of 15 consensus QTLs. Based on annotations of Arabidopsis homologs corresponding to DEGs, nine genes related to meristem growth and development were considered as promising candidates for six QTLs. CONCLUSION In this study, we discovered the first repeatable major QTL for pod number in rapeseed. In addition, RNA sequencing was performed for SAM in rapeseed, which provides new insights into the determination of floral organ number. Furthermore, the integration of DEGs and QTLs identified promising candidates for further gene cloning and mechanism study.
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Affiliation(s)
- Jiang Ye
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, 430062, China
| | - Yuhua Yang
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, 430062, China
| | - Bo Chen
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jiaqin Shi
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, 430062, China.
| | - Meizhong Luo
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jiepeng Zhan
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, 430062, China
| | - Xinfa Wang
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, 430062, China
| | - Guihua Liu
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, 430062, China
| | - Hanzhong Wang
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, 430062, China.
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Galsurker O, Doron-Faigenboim A, Teper-Bamnolker P, Daus A, Fridman Y, Lers A, Eshel D. Cellular and Molecular Changes Associated with Onion Skin Formation Suggest Involvement of Programmed Cell Death. FRONTIERS IN PLANT SCIENCE 2016; 7:2031. [PMID: 28119713 PMCID: PMC5220068 DOI: 10.3389/fpls.2016.02031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 12/19/2016] [Indexed: 05/07/2023]
Abstract
Skin formation of onion (Allium cepa L.) bulb involves scale desiccation accompanied by scale senescence, resulting in cell death and tissue browning. Understanding the mechanism of skin formation is essential to improving onion skin and bulb qualities. Although onion skin plays a crucial role in postharvest onion storage and shelf life, its formation is poorly understood. We investigated the mode of cell death in the outermost scales that are destined to form the onion skin. Surprisingly, fluorescein diacetate staining and scanning electron microscopy indicated that the outer scale desiccates from the inside out. This striking observation suggests that cell death in the outer scales, during skin formation, is an internal and organized process that does not derive only from air desiccation. DNA fragmentation, a known hallmark of programmed cell death (PCD), was revealed in the outer scales and gradually decreased toward the inner scales of the bulb. Transmission electron microscopy further revealed PCD-related structural alterations in the outer scales which were absent from the inner scales. De novo transcriptome assembly for three different scales: 1st (outer), 5th (intermediate) and 8th (inner) fleshy scales identified 2,542 differentially expressed genes among them. GO enrichment for cluster analysis revealed increasing metabolic processes in the outer senescent scale related to defense response, PCD processes, carbohydrate metabolism and flavonoid biosynthesis, whereas increased metabolism and developmental growth processes were identified in the inner scales. High expression levels of PCD-related genes were identified in the outer scale compared to the inner ones, highlighting the involvement of PCD in outer-skin development. These findings suggest that a program to form the dry protective skin exists and functions only in the outer scales of onion.
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Affiliation(s)
- Ortal Galsurker
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
- The Robert H. Smith Institute of Field Crops and Vegetables, Robert H. Smith Faculty of Agriculture Food and Environment, The Hebrew University of JerusalemRehovot, Israel
| | - Adi Doron-Faigenboim
- Institute of Plant Sciences, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
| | - Paula Teper-Bamnolker
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
| | - Avinoam Daus
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
| | - Yael Fridman
- The Alexander Silberman Institute of Life Science, Edmond Safra Campus (G Ram), The Hebrew UniversityJerusalem, Israel
| | - Amnon Lers
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
| | - Dani Eshel
- Department of Postharvest Science of Fresh Produce, The Volcani Center, Agricultural Research OrganizationRishon LeZion, Israel
- *Correspondence: Dani Eshel,
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Microarray expression analysis of the main inflorescence in Brassica napus. PLoS One 2014; 9:e102024. [PMID: 25007212 PMCID: PMC4090195 DOI: 10.1371/journal.pone.0102024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 06/13/2014] [Indexed: 01/13/2023] Open
Abstract
The effect of the number of pods on the main inflorescence (NPMI) on seed yield in Brassica napus plants grown at high density is a topic of great economic and scientific interest. Here, we sought to identify patterns of gene expression that determine the NPMI during inflorescence differentiation. We monitored gene expression profiles in the main inflorescence of two B. napus F6 RIL pools, each composed of nine lines with a low or high NPMI, and their parental lines, Zhongshuang 11 (ZS11) and 73290, using a Brassica 90K elements oligonucleotide array. We identified 4,805 genes that were differentially expressed (≥1.5 fold-change) between the low- and high-NPMI samples. Of these, 82.8% had been annotated and 17.2% shared no significant homology with any known genes. About 31 enriched GO clusters were identified amongst the differentially expressed genes (DEGs), including those involved in hormone responses, development regulation, carbohydrate metabolism, signal transduction, and transcription regulation. Furthermore, 92.8% of the DEGs mapped to chromosomes that originated from B. rapa and B. oleracea, and 1.6% of the DEGs co-localized with two QTL intervals (PMI10 and PMI11) known to be associated with the NPMI. Overexpression of BnTPI, which co-localized with PMI10, in Arabidopsis suggested that this gene increases the NPMI. This study provides insight into the molecular factors underlying inflorescence architecture, NPMI determination and, consequently, seed yield in B. napus.
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Zhang H, Yang B, Liu WZ, Li H, Wang L, Wang B, Deng M, Liang W, Deyholos MK, Jiang YQ. Identification and characterization of CBL and CIPK gene families in canola (Brassica napus L.). BMC PLANT BIOLOGY 2014; 14:8. [PMID: 24397480 PMCID: PMC3890537 DOI: 10.1186/1471-2229-14-8] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 12/10/2013] [Indexed: 05/17/2023]
Abstract
BACKGROUND Canola (Brassica napus L.) is one of the most important oil-producing crops in China and worldwide. The yield and quality of canola is frequently threatened by environmental stresses including drought, cold and high salinity. Calcium is a ubiquitous intracellular secondary messenger in plants. Calcineurin B-like proteins (CBLs) are Ca2+ sensors and regulate a group of Ser/Thr protein kinases called CBL-interacting protein kinases (CIPKs). Although the CBL-CIPK network has been demonstrated to play crucial roles in plant development and responses to various environmental stresses in Arabidopsis, little is known about their function in canola. RESULTS In the present study, we identified seven CBL and 23 CIPK genes from canola by database mining and cloning of cDNA sequences of six CBLs and 17 CIPKs. Phylogenetic analysis of CBL and CIPK gene families across a variety of species suggested genome duplication and diversification. The subcellular localization of three BnaCBLs and two BnaCIPKs were determined using green fluorescence protein (GFP) as the reporter. We also demonstrated interactions between six BnaCBLs and 17 BnaCIPKs using yeast two-hybrid assay, and a subset of interactions were further confirmed by bimolecular fluorescence complementation (BiFC). Furthermore, the expression levels of six selected BnaCBL and 12 BnaCIPK genes in response to salt, drought, cold, heat, ABA, methyl viologen (MV) and low potassium were examined by quantitative RT-PCR and these CBL or CIPK genes were found to respond to multiple stimuli, suggesting that the canola CBL-CIPK network may be a point of convergence for several different signaling pathways. We also performed a comparison of interaction patterns and expression profiles of CBL and CIPK in Arabidospsis, canola and rice, to examine the differences between orthologs, highlighting the importance of studying CBL-CIPK in canola as a prerequisite for improvement of this crop. CONCLUSIONS Our findings indicate that CBL and CIPK family members may form a dynamic complex to respond to different abiotic or hormone signaling. Our comparative analyses of the CBL-CIPK network between canola, Arabidopsis and rice highlight functional differences and the necessity to study CBL-CIPK gene functions in canola. Our data constitute a valuable resource for CBL and CPK genomics.
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Affiliation(s)
- Hanfeng Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Bo Yang
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Wu-Zhen Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Hongwei Li
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Lei Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Boya Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Min Deng
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Wanwan Liang
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Michael K Deyholos
- Department of Biological Sciences, University of Alberta, Edmonton T6G 2E9, Canada
| | - Yuan-Qing Jiang
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi 712100, China
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10
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Becker MG, Hsu SW, Harada JJ, Belmonte MF. Genomic dissection of the seed. FRONTIERS IN PLANT SCIENCE 2014; 5:464. [PMID: 25309563 PMCID: PMC4162360 DOI: 10.3389/fpls.2014.00464] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 08/26/2014] [Indexed: 05/20/2023]
Abstract
Seeds play an integral role in the global food supply and account for more than 70% of the calories that we consume on a daily basis. To meet the demands of an increasing population, scientists are turning to seed genomics research to find new and innovative ways to increase food production. Seed genomics is evolving rapidly, and the information produced from seed genomics research has exploded over the past two decades. Advances in modern sequencing strategies that profile every molecule in every cell, tissue, and organ and the emergence of new model systems have provided the tools necessary to unravel many of the biological processes underlying seed development. Despite these advances, the analyses and mining of existing seed genomics data remain a monumental task for plant biologists. This review summarizes seed region and subregion genomic data that are currently available for existing and emerging oilseed models. We provide insight into the development of tools on how to analyze large-scale datasets.
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Affiliation(s)
- Michael G. Becker
- Department of Biological Sciences, University of Manitoba, Winnipeg, MBCanada
| | - Ssu-Wei Hsu
- Department of Plant Biology, University of California Davis, Davis, CAUSA
| | - John J. Harada
- Department of Plant Biology, University of California Davis, Davis, CAUSA
| | - Mark F. Belmonte
- Department of Biological Sciences, University of Manitoba, Winnipeg, MBCanada
- *Correspondence: Mark F. Belmonte, Department of Biological Sciences, University of Manitoba, 50 Sifton Road, Winnipeg, MB R3T 2N2, Canada e-mail:
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De novo transcriptome of Brassica juncea seed coat and identification of genes for the biosynthesis of flavonoids. PLoS One 2013; 8:e71110. [PMID: 23990927 PMCID: PMC3747200 DOI: 10.1371/journal.pone.0071110] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 06/25/2013] [Indexed: 01/10/2023] Open
Abstract
Brassica juncea, a worldwide cultivated crop plant, produces seeds of different colors. Seed pigmentation is due to the deposition in endothelial cells of proanthocyanidins (PAs), end products from a branch of flavonoid biosynthetic pathway. To elucidate the gene regulatory network of seed pigmentation in B. juncea, transcriptomes in seed coat of a yellow-seeded inbred line and its brown-seeded near- isogenic line were sequenced using the next-generation sequencing platform Illumina/Solexa and de novo assembled. Over 116 million high-quality reads were assembled into 69,605 unigenes, of which about 71.5% (49,758 unigenes) were aligned to Nr protein database with a cut-off E-value of 10−5. RPKM analysis showed that the brown-seeded testa up-regulated 802 unigenes and down-regulated 502 unigenes as compared to the yellow-seeded one. Biological pathway analysis revealed the involvement of forty six unigenes in flavonoid biosynthesis. The unigenes encoding dihydroflavonol reductase (DFR), leucoantho-cyanidin dioxygenase (LDOX) and anthocyanidin reductase (ANR) for late flavonoid biosynthesis were not expressed at all or at a very low level in the yellow-seeded testa, which implied that these genes for PAs biosynthesis be associated with seed color of B. juncea, as confirmed by qRT-PCR analysis of these genes. To our knowledge, it is the first time to sequence the transcriptome of seed coat in Brassica juncea. The unigene sequences obtained in this study will not only lay the foundations for insight into the molecular mechanisms underlying seed pigmentation in B.juncea, but also provide the basis for further genomics research on this species or its allies.
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Qu C, Fu F, Lu K, Zhang K, Wang R, Xu X, Wang M, Lu J, Wan H, Zhanglin T, Li J. Differential accumulation of phenolic compounds and expression of related genes in black- and yellow-seeded Brassica napus. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:2885-98. [PMID: 23698630 PMCID: PMC3697950 DOI: 10.1093/jxb/ert148] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Developing yellow-seeded Brassica napus (rapeseed) with improved qualities is a major breeding goal. The intermediate and final metabolites of the phenylpropanoid and flavonoid pathways affect not only oil quality but also seed coat colour of B. napus. Here, the accumulation of phenolic compounds was analysed in the seed coats of black-seeded (ZY821) and yellow-seeded (GH06) B. napus. Using toluidine blue O staining and liquid chromatography-mass spectrometry, histochemical and biochemical differences were identified in the accumulation of phenolic compounds between ZY821 and GH06. Two and 13 unique flavonol derivatives were detected in ZY821 and GH06, respectively. Quantitative real-time PCR analysis revealed significant differences between ZY821 and GH06 in the expression of common phenylpropanoid biosynthetic genes (BnPAL and BnC4H), common flavonoid biosynthetic genes (BnTT4 and BnTT6), anthocyanin- and proanthocyandin-specific genes (BnTT3 and BnTT18), proanthocyandin-specific genes (BnTT12, BnTT10, and BnUGT2) and three transcription factor genes (BnTTG1, BnTTG2, and BnTT8) that function in the flavonoid biosynthetic pathway. These data provide insight into pigment accumulation in B. napus, and serve as a useful resource for researchers analysing the formation of seed coat colour and the underlying regulatory mechanisms in B. napus.
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Affiliation(s)
- Cunmin Qu
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
- *These authors contributed equally to this work
| | - Fuyou Fu
- Agriculture and Agri-Food Canada, Saskatoon Research Centre, 107 Science Place, S7N 02X, Saskatoon Saskatchewan, Canada
- *These authors contributed equally to this work
| | - Kun Lu
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
- *These authors contributed equally to this work
| | - Kai Zhang
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
| | - Rui Wang
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
| | - Xinfu Xu
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
| | - Min Wang
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
| | - Junxing Lu
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
| | - Huafang Wan
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
| | - Tang Zhanglin
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
| | - Jiana Li
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716, People’s Republic of China
- Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing 400716, People’s Republic of China
- To whom correspondence should be addressed. E-mail:
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Chen G, Deng W, Peng F, Truksa M, Singer S, Snyder CL, Mietkiewska E, Weselake RJ. Brassica napus TT16 homologs with different genomic origins and expression levels encode proteins that regulate a broad range of endothelium-associated genes at the transcriptional level. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 74:663-77. [PMID: 23425240 DOI: 10.1111/tpj.12151] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 02/08/2013] [Accepted: 02/14/2013] [Indexed: 05/14/2023]
Abstract
The transcription factor TRANSPARENT TESTA 16 (TT16) plays an important role in endothelial cell specification and proanthocyanidin (PA) accumulation. However, its precise regulatory function with regard to the expression of endothelial-associated genes in developing seeds, and especially in the PA-producing inner integument, remains largely unknown. Therefore, we endeavored to characterize four TT16 homologs from the allotetraploid oil crop species Brassica napus, and systematically explore their regulatory function in endothelial development. Our results indicated that all four BnTT16 genes were predominantly expressed in the early stages of seed development, but at distinct levels, and encoded functional proteins. Bntt16 RNA interference lines exhibited abnormal endothelial development and decreased PA content, while PA polymerization was not affected. In addition to the previously reported function of TT16 in the transcriptional regulation of anthocyanidin reductase (ANR) and dihydroflavonol reductase (TT3), we also determined that BnTT16 proteins played a significant role in the transcriptional regulation of five other genes involved in the PA biosynthetic pathway (P < 0.01). Moreover, we identified two genes involved in inner integument development that were strongly regulated by the BnTT16 proteins (TT2 and δ-vacuolar processing enzyme). These results will better our understanding of the precise role of TT16 in endothelial development in Brassicaceae species, and could potentially be used for the future improvement of oilseed crops.
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Affiliation(s)
- Guanqun Chen
- Alberta Innovates Phytola Centre, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada
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Heneen WK, Geleta M, Brismar K, Xiong Z, Pires JC, Hasterok R, Stoute AI, Scott RJ, King GJ, Kurup S. Seed colour loci, homoeology and linkage groups of the C genome chromosomes revealed in Brassica rapa-B. oleracea monosomic alien addition lines. ANNALS OF BOTANY 2012; 109:1227-42. [PMID: 22628364 PMCID: PMC3359914 DOI: 10.1093/aob/mcs052] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
BACKGROUND AND AIMS Brassica rapa and B. oleracea are the progenitors of oilseed rape B. napus. The addition of each chromosome of B. oleracea to the chromosome complement of B. rapa results in a series of monosomic alien addition lines (MAALs). Analysis of MAALs determines which B. oleracea chromosomes carry genes controlling specific phenotypic traits, such as seed colour. Yellow-seeded oilseed rape is a desirable breeding goal both for food and livestock feed end-uses that relate to oil, protein and fibre contents. The aims of this study included developing a missing MAAL to complement an available series, for studies on seed colour control, chromosome homoeology and assignment of linkage groups to B. oleracea chromosomes. METHODS A new batch of B. rapa-B. oleracea aneuploids was produced to generate the missing MAAL. Seed colour and other plant morphological features relevant to differentiation of MAALs were recorded. For chromosome characterization, Snow's carmine, fluorescence in situ hybridization (FISH) and genomic in situ hybridization (GISH) were used. KEY RESULTS The final MAAL was developed. Morphological traits that differentiated the MAALs comprised cotyledon number, leaf morphology, flower colour and seed colour. Seed colour was controlled by major genes on two B. oleracea chromosomes and minor genes on five other chromosomes of this species. Homoeologous pairing was largely between chromosomes with similar centromeric positions. FISH, GISH and a parallel microsatellite marker analysis defined the chromosomes in terms of their linkage groups. Conclusions A complete set of MAALs is now available for genetic, genomic, evolutionary and breeding perspectives. Defining chromosomes that carry specific genes, physical localization of DNA markers and access to established genetic linkage maps contribute to the integration of these approaches, manifested in the confirmed correspondence of linkage groups with specific chromosomes. Applications include marker-assisted selection and breeding for yellow seeds.
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Affiliation(s)
- Waheeb K Heneen
- Department of Plant Breeding and Biotechnology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
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Guan M, Li X, Guan C. Microarray analysis of differentially expressed genes between Brassica napus strains with high- and low-oleic acid contents. PLANT CELL REPORTS 2012; 31:929-43. [PMID: 22203212 DOI: 10.1007/s00299-011-1213-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 12/02/2011] [Accepted: 12/12/2011] [Indexed: 05/03/2023]
Abstract
An increase in oleic acid (C18:1) content is a desirable trait. Despite the critical roles of the two desaturases, FAD2 and FAD3, in the control of fatty acid desaturation, a dispute remains over whether inactivation of their genes alone is sufficient enough to generate the high-oleic trait. To address this question, we employed microarray technology to investigate the difference in gene expression profile between two different Brassica napus strains with high-C18:1 (71.71%) and low-C18:1 (55.6%) contents, respectively. Our study revealed 562 differentially expressed genes, of which 194 genes were up-regulated and 368 down-regulated. Based on the Gene Ontology classification, these genes were classified into 23 functional categories. Three of the up-regulated genes represent B. napus homologs of Arabidopsis genes encoding a cytosolic isoform of pyruvate kinase (AT3G55810), Δ9 acyl-lipid desaturase (AT1G06080, ADS1) and fatty acyl-ACP thioesterase B (AT1G08510), respectively. Conversely, the homologs of two Arabidopsis sequences encoding Δ9 acyl-lipid desaturase (AT2G31360, ADS2) and FAD3 desaturase (AT2G29980) were down-regulated in the high-oleic acid strain. Furthermore, 60 differentially expressed genes were classified as associated with relevant Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Collectively, our results suggest that expressing the high-oleic acid trait may require a coordinated regulation of diverse regulatory and metabolic gene networks in addition to inactivation of the FAD2 and FAD3 genes in the oilseed. A set of the differentially expressed genes identified in this study will facilitate our efforts to tap the germplasms with the potential to express the high-oleic acid trait.
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Affiliation(s)
- Mei Guan
- The Oilseed Crop Research Institute, National Oilseed Crop Improvement Center, Hunan Agricultural University, Changsha 410128, China
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Renouard S, Corbin C, Lopez T, Montguillon J, Gutierrez L, Lamblin F, Lainé E, Hano C. Abscisic acid regulates pinoresinol-lariciresinol reductase gene expression and secoisolariciresinol accumulation in developing flax (Linum usitatissimum L.) seeds. PLANTA 2012; 235:85-98. [PMID: 21837520 DOI: 10.1007/s00425-011-1492-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 07/25/2011] [Indexed: 05/24/2023]
Abstract
Secoisolariciresinol diglucoside (SDG), the main phytoestrogenic lignan of Linum usitatissimum, is accumulated in the seed coat of flax during its development and pinoresinol-lariciresinol reductase (PLR) is a key enzyme in flax for its synthesis. The promoter of LuPLR1, a flax gene encoding a pinoresinol lariciresinol reductase, contains putative regulatory boxes related to transcription activation by abscisic acid (ABA). Gel mobility shift experiments evidenced an interaction of nuclear proteins extracted from immature flax seed coat with a putative cis-acting element involved in ABA response. As ABA regulates a number of physiological events during seed development and maturation we have investigated its involvement in the regulation of this lignan synthesis by different means. ABA and SDG accumulation time courses in the seed as well as LuPLR1 expression were first determined in natural conditions. These results showed that ABA timing and localization of accumulation in the flax seed coat could be correlated with the LuPLR1 gene expression and SDG biosynthesis. Experimental modulations of ABA levels were performed by exogenous application of ABA or fluridone, an inhibitor of ABA synthesis. When submitted to exogenous ABA, immature seeds synthesized 3-times more SDG, whereas synthesis of SDG was reduced in immature seeds treated with fluridone. Similarly, the expression of LuPLR1 gene in the seed coat was up-regulated by exogenous ABA and down-regulated when fluridone was applied. These results demonstrate that SDG biosynthesis in the flax seed coat is positively controlled by ABA through the transcriptional regulation of LuPLR1 gene.
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Affiliation(s)
- Sullivan Renouard
- Laboratoire de Biologie des Ligneux et des Grandes Cultures (LBLGC), UPRES EA 1207, Antenne Scientifique Universitaire de Chartres (ASUC), Université d'Orléans, 21 rue de Loigny la Bataille, 28000, Chartres, France
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Dean G, Cao Y, Xiang D, Provart NJ, Ramsay L, Ahad A, White R, Selvaraj G, Datla R, Haughn G. Analysis of gene expression patterns during seed coat development in Arabidopsis. MOLECULAR PLANT 2011; 4:1074-91. [PMID: 21653281 DOI: 10.1093/mp/ssr040] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The seed coat is important for embryo protection, seed hydration, and dispersal. Seed coat composition is also of interest to the agricultural sector, since it impacts the nutritional value for humans and livestock alike. Although some seed coat genes have been identified, the developmental pathways controlling seed coat development are not completely elucidated, and a global genetic program associated with seed coat development has not been reported. This study uses a combination of genetic and genomic approaches in Arabidopsis thaliana to begin to address these knowledge gaps. Seed coat development is a complex process whereby the integuments of the ovule differentiate into specialized cell types. In Arabidopsis, the outermost layer of cells secretes mucilage into the apoplast and develops a secondary cell wall known as a columella. The layer beneath the epidermis, the palisade, synthesizes a secondary cell wall on its inner tangential side. The innermost layer (the pigmented layer or endothelium) produces proanthocyanidins that condense into tannins and oxidize, giving a brown color to mature seeds. Genetic separation of these cell layers was achieved using the ap2-7 and tt16-1 mutants, where the epidermis/palisade and the endothelium do not develop respectively. This genetic ablation was exploited to examine the developmental programs of these cell types by isolating and collecting seed coats at key transitions during development and performing global gene expression analysis. The data indicate that the developmental programs of the epidermis and the pigmented layer proceed relatively independently. Global expression datasets that can be used for identification of new gene candidates for seed coat development were generated. These dataset provide a comprehensive expression profile for developing seed coats in Arabidopsis, and should provide a useful resource and reference for other seed systems.
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Affiliation(s)
- Gillian Dean
- Department of Botany, University of British Columbia, 6270 University Blvd, Vancouver, BC, V6T 1Z4, Canada
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