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Wang Z, Li X, Gao XR, Dai ZR, Peng K, Jia LC, Wu YK, Liu QC, Zhai H, Gao SP, Zhao N, He SZ, Zhang H. IbMYB73 targets abscisic acid-responsive IbGER5 to regulate root growth and stress tolerance in sweet potato. PLANT PHYSIOLOGY 2024; 194:787-804. [PMID: 37815230 DOI: 10.1093/plphys/kiad532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 08/29/2023] [Accepted: 09/15/2023] [Indexed: 10/11/2023]
Abstract
Root development influences plant responses to environmental conditions, and well-developed rooting enhances plant survival under abiotic stress. However, the molecular and genetic mechanisms underlying root development and abiotic stress tolerance in plants remain unclear. In this study, we identified the MYB transcription factor-encoding gene IbMYB73 by cDNA-amplified fragment length polymorphism and RNA-seq analyses. IbMYB73 expression was greatly suppressed under abiotic stress in the roots of the salt-tolerant sweet potato (Ipomoea batatas) line ND98, and its promoter activity in roots was significantly reduced by abscisic acid (ABA), NaCl, and mannitol treatments. Overexpression of IbMYB73 significantly inhibited adventitious root growth and abiotic stress tolerance, whereas IbMYB73-RNAi plants displayed the opposite pattern. IbMYB73 influenced the transcription of genes involved in the ABA pathway. Furthermore, IbMYB73 formed homodimers and activated the transcription of ABA-responsive protein IbGER5 by binding to an MYB binding sites I motif in its promoter. IbGER5 overexpression significantly inhibited adventitious root growth and abiotic stress tolerance concomitantly with a reduction in ABA content, while IbGER5-RNAi plants showed the opposite effect. Collectively, our results demonstrated that the IbMYB73-IbGER5 module regulates ABA-dependent adventitious root growth and abiotic stress tolerance in sweet potato, which provides candidate genes for the development of elite crop varieties with well-developed root-mediated abiotic stress tolerance.
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Affiliation(s)
- Zhen Wang
- Sanya Institute of China Agricultural University, Sanya 572025, China
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Xu Li
- Sanya Institute of China Agricultural University, Sanya 572025, China
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Xiao-Ru Gao
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Zhuo-Ru Dai
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Kui Peng
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Li-Cong Jia
- Institute of Grain and Oil Crops, Yantai Academy of Agricultural Sciences, Yantai 265500, China
| | - Yin-Kui Wu
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Qing-Chang Liu
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Hong Zhai
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Shao-Pei Gao
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Ning Zhao
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Shao-Zhen He
- Sanya Institute of China Agricultural University, Sanya 572025, China
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
| | - Huan Zhang
- Sanya Institute of China Agricultural University, Sanya 572025, China
- Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing 100193, China
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Wang Y, Zhou H, He Y, Shen X, Lin S, Huang L. MYB transcription factors and their roles in the male reproductive development of flowering plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 335:111811. [PMID: 37574139 DOI: 10.1016/j.plantsci.2023.111811] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 06/29/2023] [Accepted: 07/25/2023] [Indexed: 08/15/2023]
Abstract
As one of the largest transcription factor families with complex functional differentiation in plants, the MYB transcription factors (MYB TFs) play important roles in the physiological and biochemical processes of plant growth and development. Male reproductive development, an essential part of sexual reproduction in flowering plants, is undoubtedly regulated by MYB TFs. In this review, we summarize the roles of the MYB TFs involved in the three stages of male reproductive development: pollen grains formation and maturation, filament elongation and anther dehiscence, and fertilization. Also, the potential downstream target genes and upstream regulators of these MYB TFs are discussed. Furthermore, we propose the underlying regulatory mechanisms of these MYB TFs: (1) A complex network of MYB TFs regulates various aspects of male reproductive development; (2) MYB homologous genes in different species may be functionally conserved or differentiated; (3) MYB TFs often form regulatory complexes with bHLH TFs.
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Affiliation(s)
- Yijie Wang
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China
| | - Huiyan Zhou
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China
| | - Yuanrong He
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China; Hainan Institute of Zhejiang University, Sanya, China
| | - Xiuping Shen
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China
| | - Sue Lin
- Institute of Life Sciences, College of Life and Environmental Science, Wenzhou University, Wenzhou 325000, Zhejiang, China
| | - Li Huang
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China; Hainan Institute of Zhejiang University, Sanya, China.
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Liu A, Zhu Y, Wang Y, Wang T, Zhao S, Feng K, Li L, Wu P. Molecular identification of phenylalanine ammonia lyase-encoding genes EfPALs and EfPAL2-interacting transcription factors in Euryale ferox. FRONTIERS IN PLANT SCIENCE 2023; 14:1114345. [PMID: 37008508 PMCID: PMC10064797 DOI: 10.3389/fpls.2023.1114345] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 03/08/2023] [Indexed: 06/19/2023]
Abstract
Flavonoids are one of the most important secondary metabolites in plants, and phenylalanine ammonia-lyase (PAL) is the first rate-limiting enzyme for their biosynthesis. However, detailed information on the regulation of PAL in plants is still little. In this study, PAL in E. ferox was identified and functionally analyzed, and its upstream regulatory network was investigated. Through genome-wide identification, we obtained 12 putative PAL genes from E. ferox. Phylogenetic tree and synteny analysis revealed that PAL in E. ferox was expanded and mostly preserved. Subsequently, enzyme activity assays demonstrated that EfPAL1 and EfPAL2 both catalyzed the production of cinnamic acid from phenylalanine only, with EfPAL2 exhibiting a superior enzyme activity. Overexpression of EfPAL1 and EfPAL2 in Arabidopsis thaliana, respectively, both enhanced the biosynthesis of flavonoids. Furthermore, two transcription factors, EfZAT11 and EfHY5, were identified by yeast one-hybrid library assays as binding to the promoter of EfPAL2, and further luciferase (LUC) activity analysis indicated that EfZAT11 promoted the expression of EfPAL2, while EfHY5 repressed the expression of EfPAL2. These results suggested that EfZAT11 and EfHY5 positively and negatively regulate flavonoid biosynthesis, respectively. Subcellular localization revealed that EfZAT11 and EfHY5 were localized in the nucleus. Our findings clarified the key EfPAL1 and EfPAL2 of flavonoid biosynthesis in E. ferox and established the upstream regulatory network of EfPAL2, which would provide novel information for the study of flavonoid biosynthesis mechanism.
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Affiliation(s)
- AiLian Liu
- College of Horticulture and Landscape Architecture, Yangzhou, Jiangsu, China
| | - Yue Zhu
- College of Horticulture and Landscape Architecture, Yangzhou, Jiangsu, China
| | - YuHao Wang
- College of Horticulture and Landscape Architecture, Yangzhou, Jiangsu, China
| | - TianYu Wang
- College of Horticulture and Landscape Architecture, Yangzhou, Jiangsu, China
| | - ShuPing Zhao
- College of Horticulture and Landscape Architecture, Yangzhou, Jiangsu, China
| | - Kai Feng
- College of Horticulture and Landscape Architecture, Yangzhou, Jiangsu, China
| | - LiangJun Li
- College of Horticulture and Landscape Architecture, Yangzhou, Jiangsu, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, China
| | - Peng Wu
- College of Horticulture and Landscape Architecture, Yangzhou, Jiangsu, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, China
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Pratyusha DS, Sarada DVL. MYB transcription factors-master regulators of phenylpropanoid biosynthesis and diverse developmental and stress responses. PLANT CELL REPORTS 2022; 41:2245-2260. [PMID: 36171500 DOI: 10.1007/s00299-022-02927-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Phenylpropanoids, the largest class of natural products including flavonoids, anthocyanins, monolignols and tannins perform multiple functions ranging from photosynthesis, nutrient uptake, regulating growth, cell division, maintenance of redox homeostasis and biotic and abiotic stress responses. Being sedentary life forms, plants possess several regulatory modules that increase their performance in varying environments by facilitating activation of several signaling cascades upon perception of developmental and stress signals. Of the various regulatory modules, those involving MYB transcription factors are one of the extensive groups involved in regulating the phenylpropanoid metabolic enzymes in addition to other genes. R2R3 MYB transcription factors are a class of plant-specific transcription factors that regulate the expression of structural genes involved in anthocyanin, flavonoid and monolignol biosynthesis which are indispensable to several developmental pathways and stress responses. The aim of this review is to present the regulation of the phenylpropanoid pathway by MYB transcription factors via Phospholipase D/phosphatidic acid signaling, downstream activation of the structural genes, leading to developmental and/or stress responses. Specific MYB transcription factors inducing or repressing specific structural genes of anthocyanin, flavonoid and lignin biosynthetic pathways are discussed. Further the roles of MYB in activating biotic and abiotic stress responses are delineated. While several articles have reported the role of MYB's in stress responses, they are restricted to two or three specific MYB factors. This review is a consolidation of the diverse roles of different MYB transcription factors involved both in induction and repression of anthocyanin, flavonoid, and lignin biosynthesis.
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Affiliation(s)
- Durvasula Sumana Pratyusha
- Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603 203, India
| | - Dronamraju V L Sarada
- Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603 203, India.
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Yang D, Xu H, Liu Y, Li M, Ali M, Xu X, Lu G. RNA N6-Methyladenosine Responds to Low-Temperature Stress in Tomato Anthers. FRONTIERS IN PLANT SCIENCE 2021; 12:687826. [PMID: 34149789 PMCID: PMC8213351 DOI: 10.3389/fpls.2021.687826] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 05/12/2021] [Indexed: 05/26/2023]
Abstract
Cold stress is a serious threat to subtropical crop pollen development and induces yield decline. N6-methyladenosine (m6A) is the most frequent mRNA modification and plays multiple physiological functions in plant development. However, whether m6A regulates pollen development is unclear, and its putative role in cold stress response remains unknown. Here, we observed that moderate low-temperature (MLT) stress induced pollen abortion in tomato. This phenotype was caused by disruption of tapetum development and pollen exine formation, accompanied by reduced m6A levels in tomato anther. Analysis of m6A-seq data revealed 1,805 transcripts displayed reduced m6A levels and 978 transcripts showed elevated m6A levels in MLT-stressed anthers compared with those in anthers under normal temperature. These differentially m6A enriched transcripts under MLT stress were mainly related to lipid metabolism, adenosine triphosphatase (ATPase) activity, and ATP-binding pathways. An ATP-binding transcript, SlABCG31, had significantly upregulated m6A modification levels, which was inversely correlated to the dramatically downregulated expression level. These changes correlated with higher abscisic acid (ABA) levels in anthers and disrupted pollen wall formation under low-temperature stress. Our findings characterized m6A as a novel layer of complexity in gene expression regulation and established a molecular link between m6A methylation and tomato anther development under low-temperature conditions.
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Affiliation(s)
- Dandan Yang
- Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Huachao Xu
- Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Yue Liu
- Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Mengzhuo Li
- Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Muhammad Ali
- Department of Horticulture, Zhejiang University, Hangzhou, China
| | - Xiangyang Xu
- College of Horticulture, Northeast Agricultural University, Harbin, China
| | - Gang Lu
- Department of Horticulture, Zhejiang University, Hangzhou, China
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agricultural, Zhejiang University, Hangzhou, China
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Shen X, Hu Z, Xiang X, Xu L, Cao J. Overexpression of a stamen-specific R2R3-MYB gene BcMF28 causes aberrant stamen development in transgenic Arabidopsis. Biochem Biophys Res Commun 2019; 518:726-731. [PMID: 31472956 DOI: 10.1016/j.bbrc.2019.08.119] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 08/23/2019] [Indexed: 10/26/2022]
Abstract
In flowering plants, stamen development is a complex multistage process, which is highly regulated by a series of transcription factors. In this study, BcMF28, which encodes a R2R3-MYB transcription factor, was isolated from Brassica campestris. BcMF28 is localized in the nucleus and cytoplasm, and acts as a transcriptional activator. Quantitative real-time PCR and promoter activity analysis revealed that BcMF28 was predominately expressed in inflorescences. The expression of BcMF28 was specifically detected in tapetum, developing microspores, anther endothecium, and filaments during late stamen development. The overexpression of BcMF28 in Arabidopsis resulted in aberrant stamen development, including filament shortening, anther indehiscence, and pollen abortion. Detailed analysis of anther development in transgenic plants revealed that the degeneration of septum and stomium did not occur, and endothecium lignification was affected. Furthermore, the expression levels of genes involved in the phenylpropanoid metabolism pathway were altered in BcMF28-overexpressing transgenic plants. Our results suggest that BcMF28 plays an important regulatory role during late stamen development.
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Affiliation(s)
- Xiuping Shen
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Hangzhou, 310058, China.
| | - Ziwei Hu
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Hangzhou, 310058, China.
| | - Xun Xiang
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Hangzhou, 310058, China.
| | - Liai Xu
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Hangzhou, 310058, China.
| | - Jiashu Cao
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Hangzhou, 310058, China.
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Su Y, Xiao X, Ling H, Huang N, Liu F, Su W, Zhang Y, Xu L, Muhammad K, Que Y. A dynamic degradome landscape on miRNAs and their predicted targets in sugarcane caused by Sporisorium scitamineum stress. BMC Genomics 2019; 20:57. [PMID: 30658590 PMCID: PMC6339412 DOI: 10.1186/s12864-018-5400-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Accepted: 12/20/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Sugarcane smut is a fungal disease caused by Sporisorium scitamineum. Cultivation of smut-resistant sugarcane varieties is the most effective way to control this disease. The interaction between sugarcane and S. scitamineum is a complex network system. However, to date, there is no report on the identification of microRNA (miRNA) target genes of sugarcane in response to smut pathogen infection by degradome technology. RESULTS TaqMan qRT-PCR detection and enzyme activity determination showed that S. scitamineum rapidly proliferated and incurred significant enzyme activity changes in the reactive oxygen species metabolic pathway and phenylpropanoid metabolic pathway at 2 d and 5 d after inoculation, which was the best time points to study target gene degradation during sugarcane and S. scitamineum interaction. A total of 122.33 Mb of raw data was obtained from degradome sequencing analysis of YC05-179 (smut-resistant) and ROC22 (smut-susceptible) after inoculation. The Q30 of each sample was > 93%, and the sequence used for degradation site analysis exactly matched the sugarcane reference sequence. A total of 309 target genes were predicted in sugarcane, corresponding to 97 known miRNAs and 112 novel miRNAs, and 337 degradation sites, suggesting that miRNAs can efficiently direct cleavage at multiple sites in the predicted target mRNAs. Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that the predicted target genes were involved in various regulatory processes, such as signal transduction mechanisms, inorganic ion transport and metabolism, defense mechanisms, translation, posttranslational modifications, energy production and conversion, and glycerolipid metabolism. qRT-PCR analysis of the expression level of 13 predicted target genes and their corresponding miRNAs revealed that there was no obvious negative regulatory relationship between miRNAs and their target genes. In addition, a number of putative resistance-related target genes regulated by miRNA-mediated cleavage were accumulated in sugarcane during S. scitamineum infection, suggesting that feedback regulation of miRNAs may be involved in the response of sugarcane to S. scitamineum infection. CONCLUSIONS This study elucidates the underlying response of sugarcane to S. scitamineum infection, and also provides a resource for miRNAs and their predicted target genes for smut resistance improvement in sugarcane.
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Affiliation(s)
- Yachun Su
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Xinhuan Xiao
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Hui Ling
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Ning Huang
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Feng Liu
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Weihua Su
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Yuye Zhang
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Liping Xu
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
| | - Khushi Muhammad
- Department of Genetics, Hazara University, Mansehra, 21300 Pakistan
| | - Youxiong Que
- Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, 350002 China
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MicroRNAs in durum wheat seedlings under chronic and short-term nitrogen stress. Funct Integr Genomics 2018; 18:645-657. [PMID: 29948458 DOI: 10.1007/s10142-018-0619-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 05/29/2018] [Accepted: 05/31/2018] [Indexed: 10/14/2022]
Abstract
Nitrogen is an essential macronutrient for plant growth and reproduction. In durum wheat, an appropriate nitrogen soil availability is essential for an optimal seed development. miRNAs contribute to the environmental change adaptation of plants through the regulation of important genes involved in stress processes. In this work, nitrogen stress response was evaluated in durum wheat seedlings of Ciccio and Svevo cultivars. Eight small RNA libraries from leaves and roots of chronically stressed plants were sequenced to detect conserved and novel miRNAs. A total of 294 miRNAs were identified, 7 of which were described here for the first time. The expression level of selected miRNAs and target genes was analyzed by qPCR in seedlings subjected to chronic (Ciccio and Svevo, leaves and roots) or short-term (Svevo roots) stress conditions. Some miRNAs showed an immediate stress response, and their level of expression was either maintained or returned to a basal level during a long-term stress. Other miRNAs showed a gradual up- or downregulation during the short-term stress. The newly identified miRNA ttu-novel-106 showed an immediate strongly downregulation after nitrogen stress, which was negatively correlated with the expression of MYB-A, its putative target gene. PHO2 gene was significantly upregulated after 24-48-h stress, corresponding to a downregulation of miR399b. Ttu-miR399b putative binding sites in the 5' UTR region of the Svevo PHO2 gene were identified in the A and B genomes. Both MYB-A and PHO2 genes were validated for their cleavage site using 5' RACE assay.
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Identification and Characterization of the Diverse Stress-Responsive R2R3-RMYB Transcription Factor from Hibiscus sabdariffa L. Int J Genomics 2017; 2017:2763259. [PMID: 29181384 PMCID: PMC5664376 DOI: 10.1155/2017/2763259] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 08/11/2017] [Accepted: 09/06/2017] [Indexed: 12/12/2022] Open
Abstract
Various regulatory proteins play a fundamental role to manage the healthy plant growth under stress conditions. Differential display reverse transcriptase PCR and random amplification of cDNA ends (RACE) was used to explore the osmotic stress-responsive transcripts. We identified and characterized the salt stress-responsive R2R3 type RMYB transcription factor from Hibiscus sabdariffa which has an open reading frame of 690 bp, encoding 229 long chain amino acids. In silico analysis confirmed the conserved R2 and R3 domain as well as an NLS-1 localization site. The deduced amino acids of RMYB shared 83, 81, 80, 79, 72, 71, and 66% homology with Arabidopsis thaliana, Glycine max, Oryza sativa, Zea maize, Malus domestica, Populus tremula × Populus alba, and Medicago sativa specific MYB family, respectively. We observed the gene upregulation in stem, leaf, and root tissue in response to abiotic stress. Furthermore, RMYB gene was cloned into plant expression vector under CaMV35S promoter and transformed to Gossypium hirsutum: a local cotton cultivar. Overexpression of RMYB was observed in transgenic plants under abiotic stresses which further suggests its regulatory role in response to stressful conditions. The RMYB transcription factor-overexpressing in transgenic cotton plants may be used as potential agent for the development of stress tolerant crop cultivars.
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Li P, Chen X, Sun F, Dong H. Tobacco TTG2 and ARF8 function concomitantly to control flower colouring by regulating anthocyanin synthesis genes. PLANT BIOLOGY (STUTTGART, GERMANY) 2017; 19:525-532. [PMID: 28247955 DOI: 10.1111/plb.12560] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 02/22/2017] [Indexed: 05/07/2023]
Abstract
Recently we elucidated that tobacco TTG2 cooperates with ARF8 to regulate the vegetative growth and seed production. Here we show that TTG2 and ARF8 control flower colouring by regulating expression of ANS and DFR genes, which function in anthocyanin biosynthesis. Genetic modifications that substantially altered expression levels of the TTG2 gene and production quantities of TTG2 protein were correlated with flower development and colouring. Degrees of flower colour were increased by TTG2 overexpression but decreased through TTG2 silencing, in coincidence with high and low concentrations of anthocyanins in flowers. Of five genes involved in the anthocyanin biosynthesis pathway, only ANS and DFR were TTG2-regulated and displayed enhancement and diminution of expression with TTG2 overexpression and silencing, respectively. The floral expression of ANS and DFR also needed a functional ARF8 gene, as ANS and DFR expression were attenuated by ARF8 silencing, which concomitantly diminished the role of TTG2 in anthocyanin production. While ARF8 required TTG2 to be expressed by itself and to regulate ANS and DFR expression, the concurrent presence of normally functional TTG2 and ARF8 was critical for floral production of anthocyanins and also for flower colouration. Our data suggest that TTG2 functions concomitantly with ARF8 to control degrees of flower colour by regulating expression of ANS and DFR, which are involved in the anthocyanin biosynthesis pathway. ARF8 depends on TTG2 to regulate floral expression of ANS and DFR with positive effects on anthocyanin production and flower colour.
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Affiliation(s)
- P Li
- Plant Growth and Defense Signaling Laboratory, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - X Chen
- Plant Growth and Defense Signaling Laboratory, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - F Sun
- Plant Growth and Defense Signaling Laboratory, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - H Dong
- Plant Growth and Defense Signaling Laboratory, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
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11
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Zaidi MA, O'Leary SJB, Wu S, Chabot D, Gleddie S, Laroche A, Eudes F, Robert LS. Investigating Triticeae anther gene promoter activity in transgenic Brachypodium distachyon. PLANTA 2017; 245:385-396. [PMID: 27787603 DOI: 10.1007/s00425-016-2612-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 10/18/2016] [Indexed: 06/06/2023]
Abstract
In this report, we demonstrate that Brachypodium distachyon could serve as a relatively high throughput in planta functional assay system for Triticeae anther-specific gene promoters. There remains a vast gap in our knowledge of the promoter cis-acting elements responsible for the transcriptional regulation of Triticeae anther-specific genes. In an attempt to identify conserved cis-elements, 14 pollen-specific and 8 tapetum-specific Triticeae putative promoter sequences were analyzed using different promoter sequence analysis tools. Several cis-elements were found to be enriched in these sequences and their possible role in gene expression regulation in the anther is discussed. Despite the fact that potential cis-acting elements can be identified within putative promoter sequence datasets, determining whether particular promoter sequences can in fact direct proper tissue-specific and developmental gene expression still needs to be confirmed via functional assays preferably performed in closely related plants. Transgenic functional assays with Triticeae species remain challenging and Brachypodium distachyon may represent a suitable alternative. The promoters of the triticale pollen-specific genes group 3 pollen allergen (PAL3) and group 4 pollen allergen (PAL4), as well as the tapetum-specific genes chalcone synthase-like 1 (CHSL1), from wheat and cysteine-rich protein 1 (CRP1) from triticale were fused to the green fluorescent protein gene (GFP) and analyzed in transgenic Brachypodium. This report demonstrates that this model species could serve to accelerate the functional analysis of Triticeae anther-specific gene promoters.
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Affiliation(s)
- Mohsin A Zaidi
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada
| | - Stephen J B O'Leary
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada
- National Research Council of Canada, Aquatic and Crop Resource Development, 1411 Oxford Street, Halifax, NS, B3H 3Z1, Canada
| | - Shaobo Wu
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada
- Beijing YouAn Hospital, Capital Medical University, Beijing Institute of Hepatology, No. 8 Xi Tou Tiao, You An Men Wai, Fengtai District, Beijing, 100069, People's Republic of China
| | - Denise Chabot
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada
| | - Steve Gleddie
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada
| | - André Laroche
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, T1J 4B1, Canada
| | - François Eudes
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, T1J 4B1, Canada
| | - Laurian S Robert
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada.
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12
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Xiu Y, Iqbal A, Zhu C, Wu G, Chang Y, Li N, Cao Y, Zhang W, Zeng H, Chen S, Wang H. Improvement and transcriptome analysis of root architecture by overexpression of Fraxinus pennsylvanica DREB2A transcription factor in Robinia pseudoacacia L. 'Idaho'. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:1456-69. [PMID: 26806173 PMCID: PMC5066641 DOI: 10.1111/pbi.12509] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Revised: 10/27/2015] [Accepted: 11/06/2015] [Indexed: 05/04/2023]
Abstract
Transcription factors play a key role to enable plants to cope with abiotic stresses. DREB2 regulates the expression of several stress-inducible genes and constitutes major hubs in the water stress signalling webs. We cloned and characterized a novel gene encoding the FpDREB2A transcription factor from Fraxinus pennsylvanica, and a yeast activity assay confirmed its DRE binding and transcription activation. Overexpression of FpDREB2A in R. pseudoacacia showed enhanced resistance to drought stress. The transgenic plant survival rate was significantly higher than that of WT in soil drying and re-watering treatments. Transgenic lines showed a dramatic change in root architecture, and horizontal and vertical roots were found in transgenic plants compared to WT. The vertical roots penetrated in the field soil to more than 60 cm deep, while horizontal roots expanded within the top 20-30 cm of the soil. A physiological test demonstrated that chlorophyll contents were more gradually reduced and that soluble sugars and proline levels elevated more sharply but malondialdehyde level stayed the same (P < 0.05). Plant hormone levels of abscisic acid and IAA were higher than that of WT, while gibberellins and zeatin riboside were found to be lower. The root transcriptomes were sequenced and annotated into 2011 differential expression genes (DEGs). The DEGs were categorized in 149 pathways and were found to be involved in plant hormone signalling, transcription factors, stimulus responses, phenylalanine, carbohydrate and other metabolic pathways. The modified pathways in plant hormone signalling are thought to be the main cause of greater horizontal and vertical root development, in particular.
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Affiliation(s)
- Yu Xiu
- College of Biological Sciences and Biotechnology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | - Arshad Iqbal
- College of Biological Sciences and Biotechnology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | - Chen Zhu
- College of Biological Sciences and Biotechnology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | - Guodong Wu
- College of Biological Sciences and Biotechnology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | - Yanping Chang
- College of Biological Sciences and Biotechnology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | - Na Li
- College of Biological Sciences and Biotechnology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | - Yu Cao
- College of Biological Sciences and Biotechnology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | | | - Huiming Zeng
- College of Biological Sciences and Biotechnology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
| | - Shouyi Chen
- Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Huafang Wang
- College of Biological Sciences and Biotechnology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, China
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13
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Zhang X, Liu CJ. Multifaceted regulations of gateway enzyme phenylalanine ammonia-lyase in the biosynthesis of phenylpropanoids. MOLECULAR PLANT 2015; 8:17-27. [PMID: 25578269 DOI: 10.1016/j.molp.2014.11.001] [Citation(s) in RCA: 193] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 10/25/2014] [Indexed: 05/03/2023]
Abstract
Phenylpropanoid biosynthesis in plants engenders a vast variety of aromatic metabolites critically important for their growth, development, and environmental adaptation. Some of these aromatic compounds have high economic value. Phenylalanine ammonia-lyase (PAL) is the first committed enzyme in the pathway; it diverts the central flux of carbon from the primary metabolism to the synthesis of myriad phenolics. Over the decades, many studies have shown that exquisite regulatory mechanisms at multiple levels control the transcription and the enzymatic activity of PALs. In this review, a current overview of our understanding of the complicated regulatory mechanisms governing the activity of PAL is presented; recent progress in unraveling its post-translational modifications, its metabolite feedback regulation, and its enzyme organization is highlighted.
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Affiliation(s)
- Xuebin Zhang
- Biological, Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Chang-Jun Liu
- Biological, Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
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14
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Moran Lauter AN, Peiffer GA, Yin T, Whitham SA, Cook D, Shoemaker RC, Graham MA. Identification of candidate genes involved in early iron deficiency chlorosis signaling in soybean (Glycine max) roots and leaves. BMC Genomics 2014; 15:702. [PMID: 25149281 PMCID: PMC4161901 DOI: 10.1186/1471-2164-15-702] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 08/12/2014] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Iron is an essential micronutrient for all living things, required in plants for photosynthesis, respiration and metabolism. A lack of bioavailable iron in soil leads to iron deficiency chlorosis (IDC), causing a reduction in photosynthesis and interveinal yellowing of leaves. Soybeans (Glycine max (L.) Merr.) grown in high pH soils often suffer from IDC, resulting in substantial yield losses. Iron efficient soybean cultivars maintain photosynthesis and have higher yields under IDC-promoting conditions than inefficient cultivars. RESULTS To capture signaling between roots and leaves and identify genes acting early in the iron efficient cultivar Clark, we conducted a RNA-Seq study at one and six hours after replacing iron sufficient hydroponic media (100 μM iron(III) nitrate nonahydrate) with iron deficient media (50 μM iron(III) nitrate nonahydrate). At one hour of iron stress, few genes were differentially expressed in leaves but many were already changing expression in roots. By six hours, more genes were differentially expressed in the leaves, and a massive shift was observed in the direction of gene expression in both roots and leaves. Further, there was little overlap in differentially expressed genes identified in each tissue and time point. CONCLUSIONS Genes involved in hormone signaling, regulation of DNA replication and iron uptake utilization are key aspects of the early iron-efficiency response. We observed dynamic gene expression differences between roots and leaves, suggesting the involvement of many transcription factors in eliciting rapid changes in gene expression. In roots, genes involved iron uptake and development of Casparian strips were induced one hour after iron stress. In leaves, genes involved in DNA replication and sugar signaling responded to iron deficiency. The differentially expressed genes (DEGs) and signaling components identified here represent new targets for soybean improvement.
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Affiliation(s)
- Adrienne N Moran Lauter
- />USDA-Agricultural Research Service, Corn Insects and Crop Genetics Research Unit, 1565 Agronomy Hall, Ames, IA 50011 USA
| | - Gregory A Peiffer
- />USDA-Agricultural Research Service, Corn Insects and Crop Genetics Research Unit, 1565 Agronomy Hall, Ames, IA 50011 USA
| | - Tengfei Yin
- />Department of Statistics, Iowa State University, Ames, Iowa 50011 USA
| | - Steven A Whitham
- />Department of Plant Pathology and Microbiology, Iowa State University, Ames, Iowa 50011 USA
| | - Dianne Cook
- />Department of Statistics, Iowa State University, Ames, Iowa 50011 USA
| | - Randy C Shoemaker
- />USDA-Agricultural Research Service, Corn Insects and Crop Genetics Research Unit, 1565 Agronomy Hall, Ames, IA 50011 USA
- />Department of Agronomy, Iowa State University, Ames, Iowa 50011 USA
| | - Michelle A Graham
- />USDA-Agricultural Research Service, Corn Insects and Crop Genetics Research Unit, 1565 Agronomy Hall, Ames, IA 50011 USA
- />Department of Agronomy, Iowa State University, Ames, Iowa 50011 USA
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15
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Morales AMAP, O Rourke JA, van de Mortel M, Scheider KT, Bancroft TJ, Bor M AZ, Nelson RT, Nettleton D, Baum TJ, Shoemaker RC, Frederick RD, Abdelnoor RV, Pedley KF, Whitham SA, Graham MA. Transcriptome analyses and virus induced gene silencing identify genes in the Rpp4-mediated Asian soybean rust resistance pathway. FUNCTIONAL PLANT BIOLOGY : FPB 2013; 40:1029-1047. [PMID: 32481171 DOI: 10.1071/fp12296] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 01/12/2013] [Indexed: 05/24/2023]
Abstract
Rpp4 (Resistance to Phakopsora pachyrhizi 4) confers resistance to Phakopsora pachyrhizi Sydow, the causal agent of Asian soybean rust (ASR). By combining expression profiling and virus induced gene silencing (VIGS), we are developing a genetic framework for Rpp4-mediated resistance. We measured gene expression in mock-inoculated and P. pachyrhizi-infected leaves of resistant soybean accession PI459025B (Rpp4) and the susceptible cultivar (Williams 82) across a 12-day time course. Unexpectedly, two biphasic responses were identified. In the incompatible reaction, genes induced at 12h after infection (hai) were not differentially expressed at 24 hai, but were induced at 72 hai. In contrast, genes repressed at 12 hai were not differentially expressed from 24 to 144 hai, but were repressed 216 hai and later. To differentiate between basal and resistance-gene (R-gene) mediated defence responses, we compared gene expression in Rpp4-silenced and empty vector-treated PI459025B plants 14 days after infection (dai) with P. pachyrhizi. This identified genes, including transcription factors, whose differential expression is dependent upon Rpp4. To identify differentially expressed genes conserved across multiple P. pachyrhizi resistance pathways, Rpp4 expression datasets were compared with microarray data previously generated for Rpp2 and Rpp3-mediated defence responses. Fourteen transcription factors common to all resistant and susceptible responses were identified, as well as fourteen transcription factors unique to R-gene-mediated resistance responses. These genes are targets for future P. pachyrhizi resistance research.
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Affiliation(s)
- Aguida M A P Morales
- Universidade Federal de Viçosa, Departamento de Fitotecnia, 36.570-000, Viçosa, MG, Brazil
| | - Jamie A O Rourke
- USDA-Agricultural Research Service, Plant Science Research Unit, Saint Paul, MN 55108, USA
| | - Martijn van de Mortel
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50014, USA
| | - Katherine T Scheider
- USDA- Agricultural Research Service, Foreign Disease-Weed Science Research Unit, Fort Detrick, MA 21702, USA
| | | | - Alu Zio Bor M
- Universidade Federal de Viçosa, Departamento de Fitotecnia, 36.570-000, Viçosa, MG, Brazil
| | - Rex T Nelson
- USDA-Agricultural Research Service, Corn Insects and Crop Genetics Research Unit, Ames, IA 50014, USA
| | - Dan Nettleton
- Department of Statistics, Iowa State University, Ames, IA 50014, USA
| | - Thomas J Baum
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50014, USA
| | - Randy C Shoemaker
- USDA-Agricultural Research Service, Corn Insects and Crop Genetics Research Unit, Ames, IA 50014, USA
| | - Reid D Frederick
- USDA- Agricultural Research Service, Foreign Disease-Weed Science Research Unit, Fort Detrick, MA 21702, USA
| | - Ricardo V Abdelnoor
- Laboratório de Biotecnologia Vegetal e Bioinformática, Embrapa Soja, Rod. Carlos João Strass, 86001-970, Londrina - PR, Brazil
| | - Kerry F Pedley
- USDA- Agricultural Research Service, Foreign Disease-Weed Science Research Unit, Fort Detrick, MA 21702, USA
| | - Steven A Whitham
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50014, USA
| | - Michelle A Graham
- USDA-Agricultural Research Service, Corn Insects and Crop Genetics Research Unit, Ames, IA 50014, USA
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16
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Ambawat S, Sharma P, Yadav NR, Yadav RC. MYB transcription factor genes as regulators for plant responses: an overview. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2013; 19:307-21. [PMID: 24431500 PMCID: PMC3715649 DOI: 10.1007/s12298-013-0179-1] [Citation(s) in RCA: 509] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Regulation of gene expression at the level of transcription controls many crucial biological processes. Transcription factors (TFs) play a great role in controlling cellular processes and MYB TF family is large and involved in controlling various processes like responses to biotic and abiotic stresses, development, differentiation, metabolism, defense etc. Here, we review MYB TFs with particular emphasis on their role in controlling different biological processes. This will provide valuable insights in understanding regulatory networks and associated functions to develop strategies for crop improvement.
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Affiliation(s)
- Supriya Ambawat
- Department of Molecular Biology and Biotechnology, CCS Haryana Agricultural University, Hisar, 125004 India
| | - Poonam Sharma
- Department of Molecular Biology and Biotechnology, CCS Haryana Agricultural University, Hisar, 125004 India
| | - Neelam R. Yadav
- Department of Molecular Biology and Biotechnology, CCS Haryana Agricultural University, Hisar, 125004 India
| | - Ram C. Yadav
- Department of Molecular Biology and Biotechnology, CCS Haryana Agricultural University, Hisar, 125004 India
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17
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Wong JH, Namasivayam P, Abdullah MP. The PAL2 promoter activities in relation to structural development and adaptation in Arabidopsis thaliana. PLANTA 2012; 235:267-277. [PMID: 21874349 DOI: 10.1007/s00425-011-1506-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 08/11/2011] [Indexed: 05/27/2023]
Abstract
Phenylalanine ammonia lyase (PAL) plays a major role in plant growth, development and adaptation. In Arabidopsis thaliana, the enzyme is encoded by four genes, namely PAL1, PAL2, PAL3, and PAL4 with PAL1 and PAL2 being closely related phylogenetically and functionally. PAL1 promoter activities are associated with plant development and are inducible by various stress agents. However, PAL2 promoter activities have not been functionally analysed. Here, we show that the PAL2 promoter activities are associated with the structural development of a plant and its organs. This function was inducible in an organ-specific manner by the avirulent strain of Pseudomonas syringae pv. tomato (JL1065). The PAL2 promoter was active throughout the course of the plant development particularly in the root, rosette leaf, and inflorescence stem that provide the plant with structural support. In aerial organs, the levels of PAL2 promoter activities were negatively correlated with relative positions of the organs to the rosette leaves. The promoter was inducible in the root following an inoculation by JL1065 in the leaf suggesting PAL2 to be part of an induced defence system. Our results demonstrate how the PAL2 promoter activities are being coordinated and synchronised for the structural development of the plant and its organs based on the developmental programme. Under certain stress conditions the activity may be induced in favour of certain organs.
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MESH Headings
- Adaptation, Biological
- Arabidopsis/enzymology
- Arabidopsis/genetics
- Arabidopsis/growth & development
- Arabidopsis Proteins/genetics
- Arabidopsis Proteins/metabolism
- Enzyme Assays
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Genes, Plant
- Phenylalanine Ammonia-Lyase/genetics
- Phenylalanine Ammonia-Lyase/metabolism
- Plant Components, Aerial/genetics
- Plant Components, Aerial/growth & development
- Plant Components, Aerial/metabolism
- Plant Immunity
- Plant Roots/genetics
- Plant Roots/growth & development
- Plant Roots/metabolism
- Plants, Genetically Modified/enzymology
- Plants, Genetically Modified/genetics
- Plants, Genetically Modified/growth & development
- Promoter Regions, Genetic
- Pseudomonas syringae/pathogenicity
- Sodium Chloride/pharmacology
- Stress, Physiological
- Transcriptional Activation
- Water/metabolism
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Affiliation(s)
- Jeh Haur Wong
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
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Prouse MB, Campbell MM. The interaction between MYB proteins and their target DNA binding sites. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2012; 1819:67-77. [DOI: 10.1016/j.bbagrm.2011.10.010] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 10/17/2011] [Accepted: 10/18/2011] [Indexed: 02/02/2023]
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19
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Affiliation(s)
- Arnab Bhattacharya
- Department of Botany, Cytogenetics and Plant Breeding Section, Kalyani University
| | - Animesh K. Datta
- Department of Botany, Cytogenetics and Plant Breeding Section, Kalyani University
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20
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Osakabe Y, Osakabe K, Chiang VL. Characterization of the tissue-specific expression of phenylalanine ammonia-lyase gene promoter from loblolly pine (Pinus taeda) in Nicotiana tabacum. PLANT CELL REPORTS 2009; 28:1309-17. [PMID: 19636564 DOI: 10.1007/s00299-009-0707-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Revised: 03/18/2009] [Accepted: 04/20/2009] [Indexed: 05/28/2023]
Abstract
We isolated the 5' flanking region of a gene for phenylalanine ammonia-lyase (PAL; EC 4.3.1.5) from Pinus taeda, PtaPAL. To investigate the tissue-specific expression of the PtaPAL promoter, histochemical assay of GUS activity was performed using the transgenic tobacco expressing the PtaPAL promoter-GUS. The region of -897 to -420 in PtaPAL promoter showed high activities in the secondary xylem and response to bending stress. To characterize the cis-regulatory functions of the promoters for enzymes in phenylpropanoid biosynthesis, we examined the activity of chimeric promoters of PtaPAL and a 4-coumarate CoA ligase, Pta4CL alpha. The chimeric promoter showed similar activity as the Pta4CL alpha promoter. Electrophoretic mobility shift assays implicated -897 to -674 of PtaPAL promoter containing cis-elements of the expression in xylem of Pinus taeda. The results suggested that AC elements of PtaPAL have multiple functions in the expression under the various developmental stages and stress conditions in the transgenic tobacco.
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Affiliation(s)
- Yuriko Osakabe
- Plant Biotechnology Research Center, School of Forestry and Wood Products, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931, USA.
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21
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Du H, Zhang L, Liu L, Tang XF, Yang WJ, Wu YM, Huang YB, Tang YX. Biochemical and molecular characterization of plant MYB transcription factor family. BIOCHEMISTRY (MOSCOW) 2009; 74:1-11. [PMID: 19232042 DOI: 10.1134/s0006297909010015] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
MYB genes are widely distributed in higher plants and comprise one of the largest transcription factors, which are characterized by the presence of a highly conserved MYB domain at their N-termini. Over recent decades, biochemical and molecular characterizations of MYB have been extensively studied and reported to be involved in many physiological and biochemical processes. This review describes current knowledge of their structure characteristic, classification, multi-functionality, mechanism of combinational control, evolution, and function redundancy. It shows that the MYB transcription factors play a key role in plant development, such as secondary metabolism, hormone signal transduction, disease resistance, cell shape, organ development, etc. Furthermore, the expression of some members of the MYB family shows tissue-specificity.
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Affiliation(s)
- Hai Du
- Maize Research Institute, Sichuan Agricultural University, Yaan Sichuan 625014, China
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22
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Yamaoka S, Leaver CJ. EMB2473/MIRO1, an Arabidopsis Miro GTPase, is required for embryogenesis and influences mitochondrial morphology in pollen. THE PLANT CELL 2008; 20:589-601. [PMID: 18344283 PMCID: PMC2329936 DOI: 10.1105/tpc.107.055756] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Revised: 01/19/2008] [Accepted: 02/29/2008] [Indexed: 05/18/2023]
Abstract
The regulation of mitochondrial biogenesis, subcellular distribution, morphology, and metabolism are essential for all aspects of plant growth and development. However, the molecular mechanisms involved are still unclear. Here, we describe an analysis of the three Arabidopsis thaliana orthologs of the evolutionarily conserved Miro GTPases. Two of the genes, MIRO1 and MIRO2, are transcribed ubiquitously throughout the plant tissues, and their gene products localize to mitochondria via their C-terminal transmembrane domains. While insertional mutations in the MIRO2 gene do not have any visible impact on plant development, an insertional mutation in the MIRO1 gene is lethal during embryogenesis at the zygote to four-terminal-cell embryo stage. It also substantially impairs pollen germination and tube growth. Laser confocal and transmission electron microscopy revealed that the miro1 mutant pollen exhibits abnormally enlarged or tube-like mitochondrial morphology, leading to the disruption of continuous streaming of mitochondria in the growing pollen tube. Our findings suggest that mitochondrial morphology is influenced by MIRO1 and plays a vital role during embryogenesis and pollen tube growth.
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Affiliation(s)
- Shohei Yamaoka
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
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23
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Gupta V, Khurana R, Tyagi AK. Promoters of two anther-specific genes confer organ-specific gene expression in a stage-specific manner in transgenic systems. PLANT CELL REPORTS 2007; 26:1919-31. [PMID: 17661051 DOI: 10.1007/s00299-007-0414-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2007] [Revised: 07/04/2007] [Accepted: 07/08/2007] [Indexed: 05/16/2023]
Abstract
Differential screening of a stage-specific cDNA library of Indica rice has been used to identify two genes expressed in pre-pollination stage panicles, namely OSIPA and OSIPK coding for proteins similar to expansins/pollen allergens and calcium-dependent protein kinases (CDPK), respectively. Northern analysis and in situ hybridizations indicate that OSIPA expresses exclusively in pollen while OSIPK expresses in pollen as well as anther wall. Promoters of these two anther-specific genes show the presence of various cis-acting elements (GTGA and AGAAA) known to confer anther/pollen-specific gene expression. Organ/tissue-specific activity and strength of their regulatory regions have been determined in transgenic systems, i.e., tobacco and Arabidopsis. A unique temporal activity of these two promoters was observed during various developmental stages of anther/pollen. Promoter of OSIPA is active during the late stages of pollen development and remains active till the anthesis, whereas, OSIPK promoter is active to a low level in developing anther till the pollen matures. OSIPK promoter activity diminishes before anthesis. Both promoters show a potential to target expression of the gene of interest in developmental stage-specific manner and can help engineer pollen-specific traits like male-sterility in plants.
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Affiliation(s)
- Vikrant Gupta
- Interdisciplinary Centre for Plant Genomics and Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi 110021, India
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24
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Zhang ZB, Zhu J, Gao JF, Wang C, Li H, Li H, Zhang HQ, Zhang S, Wang DM, Wang QX, Huang H, Xia HJ, Yang ZN. Transcription factor AtMYB103 is required for anther development by regulating tapetum development, callose dissolution and exine formation in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2007; 52:528-38. [PMID: 17727613 DOI: 10.1111/j.1365-313x.2007.03254.x] [Citation(s) in RCA: 258] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Downregulation of the transcription factor AtMYB103 using transgenic technology results in early tapetal degeneration and pollen aberration during anther development in Arabidopsis thaliana. This paper describes the functional analysis of the AtMYB103 gene in three knock-out mutants. Two male sterile mutants, ms188-1 and ms188-2, were generated by ethyl-methane sulfonate (EMS) mutagenesis. A map-based cloning approach was used, and ms188 was mapped to a 95.8-kb region on chromosome 5 containing an AtMYB103 transcription factor. Sequence analysis revealed that ms188-1 had a pre-mature stop codon in the AtMYB103 coding region, whereas ms188-2 had a CCT-->CTT base-pair change in the first exon of AtMYB103, which resulted in the replacement of a proline by a leucine residue in the R2R3 domain. The third mutant, an AtMYB103 transposon-tagging line, also showed a male sterile phenotype. Allelism tests indicated that MS188 and AtMYB103 belong to the same locus. Cytological observation revealed defective tapetum development and altered callose dissolution in ms188 plants. Additionally, most of the microspores in mature anthers were degraded and surviving microspores lacked exine. AtMYB103 encoded an R2R3 MYB protein that is predominantly located in the nucleus. Real-time RT-PCR analysis indicated that the callase-related gene A6 was regulated by AtMYB103. Expression of the exine formation gene MS2 was not detected in mutant anthers. These results implicate that AtMYB103 plays an important role in tapetum development, callose dissolution and exine formation in A. thaliana anthers.
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Affiliation(s)
- Zai-Bao Zhang
- College of Life and Environmental Sciences, Shanghai Normal University, Shanghai 200234, China
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25
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Yang C, Xu Z, Song J, Conner K, Vizcay Barrena G, Wilson ZA. Arabidopsis MYB26/MALE STERILE35 regulates secondary thickening in the endothecium and is essential for anther dehiscence. THE PLANT CELL 2007; 19:534-48. [PMID: 17329564 PMCID: PMC1867336 DOI: 10.1105/tpc.106.046391] [Citation(s) in RCA: 204] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 01/06/2007] [Accepted: 02/05/2007] [Indexed: 05/14/2023]
Abstract
The Arabidopsis thaliana MYB26/MALE STERILE35 (MS35) gene is critical for the development of secondary thickening in the anther endothecium and subsequent dehiscence. MYB26 is localized to the nucleus and regulates endothecial development and secondary thickening in a cell-specific manner in the anther. MYB26 expression is seen in anthers and also in the style and nectaries, although there is no effect on female fertility in the ms35 mutant. MYB26 expression in anthers occurs early during endothecial development, with maximal expression during pollen mitosis I and bicellular stages, indicating a regulatory role in specifying early endothecial cell development. Overexpression of MYB26 results in ectopic secondary thickening in both Arabidopsis and tobacco (Nicotiana tabacum) plants, predominantly within the epidermal tissues. MYB26 regulates a number of genes linked to secondary thickening, including IRREGULAR XYLEM1 (IRX1), IRX3, IRX8, and IRX12. Changes in expression were also detected in two NAC domain genes, NAC SECONDARY WALL-PROMOTING FACTOR1 (NST1) and NST2, which have been linked to secondary thickening in the anther endothecium. These data indicate that MYB26 regulates NST1 and NST2 expression and in turn controls the process of secondary thickening. Therefore, MYB26 appears to function in a regulatory role involved in determining endothecial cell development within the anther and acts upstream of the lignin biosynthesis pathway.
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Affiliation(s)
- Caiyun Yang
- Plant Sciences Division, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicstershire LE12 5RD, United Kingdom
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26
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Tsuji H, Aya K, Ueguchi-Tanaka M, Shimada Y, Nakazono M, Watanabe R, Nishizawa NK, Gomi K, Shimada A, Kitano H, Ashikari M, Matsuoka M. GAMYB controls different sets of genes and is differentially regulated by microRNA in aleurone cells and anthers. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 47:427-44. [PMID: 16792694 DOI: 10.1111/j.1365-313x.2006.02795.x] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
GAMYB is a component of gibberellin (GA) signaling in cereal aleurone cells, and has an important role in flower development. However, it is unclear how GAMYB function is regulated. We examined the involvement of a microRNA, miR159, in the regulation of GAMYB expression in cereal aleurone cells and flower development. In aleurone cells, no miR159 expression was observed with or without GA treatment, suggesting that miR159 is not involved in the regulation of GAMYB and GAMYB-like genes in this tissue. miR159 was expressed in tissues other than aleurone, and miR159 over-expressors showed similar but more severe phenotypes than the gamyb mutant. GAMYB and GAMYB-like genes are co-expressed with miR159 in anthers, and the mRNA levels for GAMYB and GAMYB-like genes are negatively correlated with miR159 levels during anther development. Thus, OsGAMYB and OsGAMYB-like genes are regulated by miR159 in flowers. A microarray analysis revealed that OsGAMYB and its upstream regulator SLR1 are involved in the regulation of almost all GA-mediated gene expression in rice aleurone cells. Moreover, different sets of genes are regulated by GAMYB in aleurone cells and anthers. GAMYB binds directly to promoter regions of its target genes in anthers as well as aleurone cells. Based on these observations, we suggest that the regulation of GAMYB expression and GAMYB function are different in aleurone cells and flowers in rice.
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Affiliation(s)
- Hiroyuki Tsuji
- Bioscience and Biotechnology Center, Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan
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Gális I, Simek P, Narisawa T, Sasaki M, Horiguchi T, Fukuda H, Matsuoka K. A novel R2R3 MYB transcription factor NtMYBJS1 is a methyl jasmonate-dependent regulator of phenylpropanoid-conjugate biosynthesis in tobacco. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 46:573-92. [PMID: 16640595 DOI: 10.1111/j.1365-313x.2006.02719.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Target metabolic and large-scale transcriptomic analyses of tobacco (Nicotiana tabacum L.) Bright Yellow-2 (BY-2) cells were employed to identify novel gene(s) involved in methyl jasmonate (MJ)-dependent function in plants. At the metabolic level, we describe the specific accumulation of several phenylpropanoid-polyamine conjugates in MJ-treated BY-2 cells. Furthermore, global gene expression analysis of MJ-treated cells using a 16K cDNA microarray containing expressed sequence tags (ESTs) from BY-2 cells revealed 828 genes that were upregulated by MJ treatment within 48 h. Using time-course expression data we identified a novel MJ-inducible R2R3 MYB-type transcription factor (NtMYBJS1) that was co-expressed in a close temporal pattern with the core phenylpropanoid genes phenylalanine ammonia-lyase (PAL) and 4-coumarate:CoA ligase (4CL). Overexpression of NtMYBJS1 in tobacco BY-2 cells caused accumulation of specific phenylpropanoid conjugates in the cells. Subsequent microarray analysis of NtMYBJS1 transgenic lines revealed that a limited number of genes, including PAL and 4CL, were specifically induced in the presence of the NtMYBJS1 transgene. These results, together with results of both antisense expression analysis and of gel mobility shift assays, strongly indicate that the NtMYBJS1 protein functions in tobacco MJ signal transduction, inducing phenylpropanoid biosynthetic genes and the accumulation of phenylpropanoid-polyamine conjugates during stress.
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Affiliation(s)
- Ivan Gális
- RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi-ku,Yokohama 230-0045, Japan.
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Schuurink RC, Haring MA, Clark DG. Regulation of volatile benzenoid biosynthesis in petunia flowers. TRENDS IN PLANT SCIENCE 2006; 11:20-5. [PMID: 16226052 DOI: 10.1016/j.tplants.2005.09.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Revised: 08/30/2005] [Accepted: 09/28/2005] [Indexed: 05/04/2023]
Abstract
The petunia flower has served as a model for the study of several physiological processes including floral development, self-incompatibility, anthocyanin biosynthesis and ethylene signalling during senescence. More recently, Petunia hybrida 'Mitchell' has been used to understand the complex regulation of volatile benzenoid biosynthesis, which occurs predominantly in flower petal tissues. Benzenoid biosynthesis is temporally and circadian controlled and is tightly down-regulated by ethylene during floral senescence. Using targeted transcriptomics and gene knockouts, both biosynthetic genes and a transcription factor regulating benzenoid synthesis have been recently discovered and characterized. It appears that benzenoid production is regulated predominantly by transcriptional control of the shikimate pathway, benzenoid biosynthesis genes and S-adenosyl-methionine cycle genes.
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Affiliation(s)
- Robert C Schuurink
- Department of Plant Physiology, University of Amsterdam, Swammerdam Institute for Life Sciences, 1098 SM Amsterdam, The Netherlands.
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29
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Maeda K, Kimura S, Demura T, Takeda J, Ozeki Y. DcMYB1 acts as a transcriptional activator of the carrot phenylalanine ammonia-lyase gene (DcPAL1) in response to elicitor treatment, UV-B irradiation and the dilution effect. PLANT MOLECULAR BIOLOGY 2005; 59:739-52. [PMID: 16270227 DOI: 10.1007/s11103-005-0910-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2005] [Accepted: 07/13/2005] [Indexed: 05/05/2023]
Abstract
Expression of a carrot phenylalanine ammonia-lyase (PAL) gene (DcPAL1) in suspension-cultured carrot cells is induced by treatment with a fungal elicitor, ultraviolet B (UV-B) irradiation, and by transferring and diluting cells with fresh medium (the dilution effect). Box-L-like sequences are known as important cis-elements of genes for enzymes involved in the phenylpropanoid biosynthetic pathway. Six sequences, box-L0 to box-L5, exist in the DcPAL1 gene promoter region. In this study, we isolated cDNA encoding the R2R3 type of MYB transcription factor, DcMYB1, using yeast one-hybrid screening with box-L1 or box-L5 as target elements. DcMYB1 bound to boxes-L0, L1, L3/4, and L5 sequences (ACC(A/T)(A/T)CC) in vitro, and in yeast cells and carrot protoplasts. Transient expression of DcMYB1 could up-regulate DcPAL1 promoter activity in carrot protoplasts. Results of the transient expression experiment for the deletion-mutated promoters of boxes-L0, L1, L3, and L5 suggest that these box-L-like sequences were required for the complete activation of the DcPAL1 promoter by DcMYB1. Expression of DcMYB1 transcripts was induced 0.5 h after elicitor treatment or UV-B irradiation, and 2 h after the dilution effect. Induction of DcPAL1 expression occurred 1 h after DcMYB1 expression in all stress treatments, and repression of DcMYB1 expression by RNA interference caused cessation of the up-regulation of DcPAL1 expression in the elicitor treatment or with UV-B irradiation. These results suggest that DcMYB1 is the main regulatory factor acting on box-L sequences in the DcPAL1 gene that respond to environmental cues.
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MESH Headings
- Base Sequence
- Cells, Cultured
- Cloning, Molecular
- DNA, Complementary/genetics
- DNA, Plant/genetics
- DNA, Plant/metabolism
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Daucus carota/drug effects
- Daucus carota/enzymology
- Daucus carota/genetics
- Daucus carota/radiation effects
- Gene Deletion
- Gene Expression Regulation, Plant/drug effects
- Gene Expression Regulation, Plant/radiation effects
- Phenylalanine Ammonia-Lyase/genetics
- Phenylalanine Ammonia-Lyase/metabolism
- Phylogeny
- Plant Growth Regulators/pharmacology
- Promoter Regions, Genetic/genetics
- Protein Binding
- Trans-Activators/genetics
- Trans-Activators/metabolism
- Transcription, Genetic/drug effects
- Transcription, Genetic/radiation effects
- Ultraviolet Rays
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Affiliation(s)
- Kazuhiro Maeda
- Department of Biotechnology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, 184-8588 Koganei, Tokyo, Japan
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Verdonk JC, Haring MA, van Tunen AJ, Schuurink RC. ODORANT1 regulates fragrance biosynthesis in petunia flowers. THE PLANT CELL 2005; 17:1612-24. [PMID: 15805488 PMCID: PMC1091778 DOI: 10.1105/tpc.104.028837] [Citation(s) in RCA: 201] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2004] [Accepted: 02/22/2005] [Indexed: 05/18/2023]
Abstract
Floral scent is important to plant reproduction because it attracts pollinators to the sexual organs. Therefore, volatile emission is usually tuned to the foraging activity of the pollinators. In Petunia hybrida, volatile benzenoids determine the floral aroma. Although the pathways for benzenoid biosynthesis have been characterized, the enzymes involved are less well understood. How production and emission are regulated is unknown. By targeted transcriptome analyses, we identified ODORANT1 (ODO1), a member of the R2R3-type MYB family, as a candidate for the regulation of volatile benzenoids in Petunia hybrida cv W115 (Mitchell) flowers. These flowers are only fragrant in the evening and at night. Transcript levels of ODO1 increased before the onset of volatile emission and decreased when volatile emission declined. Downregulation of ODO1 in transgenic P. hybrida Mitchell plants strongly reduced volatile benzenoid levels through decreased synthesis of precursors from the shikimate pathway. The transcript levels of several genes in this pathway were reduced by suppression of ODO1 expression. Moreover, ODO1 could activate the promoter of the 5-enol-pyruvylshikimate-3-phosphate synthase gene. Flower pigmentation, which is furnished from the same shikimate precursors, was not influenced because color and scent biosynthesis occur at different developmental stages. Our studies identify ODO1 as a key regulator of floral scent biosynthesis.
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Affiliation(s)
- Julian C Verdonk
- Department of Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 SM Amsterdam, The Netherlands
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31
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Millar AA, Gubler F. The Arabidopsis GAMYB-like genes, MYB33 and MYB65, are microRNA-regulated genes that redundantly facilitate anther development. THE PLANT CELL 2005; 17:705-21. [PMID: 15722475 PMCID: PMC1069693 DOI: 10.1105/tpc.104.027920] [Citation(s) in RCA: 457] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Accepted: 12/20/2004] [Indexed: 05/17/2023]
Abstract
The functions of the vast majority of genes encoding R2R3 MYB domain proteins remain unknown. The closely related MYB33 and MYB65 genes of Arabidopsis thaliana have high sequence similarity to the barley (Hordeum vulgare) GAMYB gene. T-DNA insertional mutants were isolated for both genes, and a myb33 myb65 double mutant was defective in anther development. In myb33 myb65 anthers, the tapetum undergoes hypertrophy at the pollen mother cell stage, resulting in premeiotic abortion of pollen development. However, myb33 myb65 sterility was conditional, where fertility increased both under higher light or lower temperature conditions. Thus, MYB33/MYB65 facilitate, but are not essential for, anther development. Neither single mutant displayed a phenotype, implying that MYB33 and MYB65 are functionally redundant. Consistent with functional redundancy, promoter-beta-glucuronidase (GUS) fusions of MYB33 and MYB65 gave identical expression patterns in flowers (sepals, style, receptacle, anther filaments, and connective but not in anthers themselves), shoot apices, and root tips. By contrast, expression of a MYB33:GUS translational fusion in flowers was solely in young anthers (consistent with the male sterile phenotype), and no staining was seen in shoot meristems or root tips. A microRNA target sequence is present in the MYB genes, and mutating this sequence in the MYB33:GUS fusion results in an expanded expression pattern, in tissues similar to that observed in the promoter-GUS lines, implying that the microRNA target sequence is restricting MYB33 expression. Arabidopsis transformed with MYB33 containing the mutated microRNA target had dramatic pleiotrophic developmental defects, suggesting that restricting MYB33 expression, especially in the shoot apices, is essential for proper plant development.
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MESH Headings
- Alleles
- Amino Acid Sequence
- Arabidopsis/genetics
- Arabidopsis/growth & development
- Base Sequence
- DNA, Bacterial/genetics
- DNA, Plant/genetics
- Enhancer Elements, Genetic
- Gene Expression Regulation, Developmental
- Gene Expression Regulation, Plant
- Genes, Plant
- Light
- MicroRNAs/genetics
- Models, Genetic
- Mutagenesis, Insertional
- Plants, Genetically Modified
- Promoter Regions, Genetic
- RNA, Plant/genetics
- Sequence Homology, Nucleic Acid
- Temperature
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Affiliation(s)
- Anthony A Millar
- Commonwealth Scientific and Industrial Research Organization, Division of Plant Industry, Canberra ACT 2601, Australia.
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Preston J, Wheeler J, Heazlewood J, Li SF, Parish RW. AtMYB32 is required for normal pollen development in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2004; 40:979-95. [PMID: 15584962 DOI: 10.1111/j.1365-313x.2004.02280.x] [Citation(s) in RCA: 205] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
AtMYB32 gene is a member of the R2R3 MYB gene family coding for transcription factors in Arabidopsis thaliana. Its expression pattern was analysed using Northern blotting, in situ hybridization and promoter-GUS fusions. AtMYB32 is expressed in many tissues, but most strongly in the anther tapetum, stigma papillae and lateral root primordia. AtMYB32-GUS was induced in leaves and stems following wounding, and in root primordia by auxin. T-DNA insertion populations were screened and two insertion mutants were identified, both of which were partially male sterile, more than 50% of the pollen grains being distorted in shape and lacking cytoplasm. AtMYB4 is closely related to AtMYB32 and represses the CINNAMATE 4-HYDROXYLASE gene. Distorted pollen grains were produced in both AtMYB4 insertion mutant and overexpression lines. In an AtMYB32 insertion mutant, the transcript levels of the DIHYDROFLAVONOL 4-REDUCTASE and ANTHOCYANIDIN SYNTHASE genes decreased while the level of the CAFFEIC ACID 0-METHYLTRANSFERASE transcript increased. Change in the levels of AtMYB32 and AtMYB4 expression may influence pollen development by changing the flux along the phenylpropanoid pathways, affecting the composition of the pollen wall.
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Affiliation(s)
- Jeremy Preston
- Botany Department, School of Life Sciences, La Trobe University, Bundoora, Victoria 3083, Australia
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Mazarei M, Lennon KA, Puthoff DP, Rodermel SR, Baum TJ. Homologous soybean and Arabidopsis genes share responsiveness to cyst nematode infection. MOLECULAR PLANT PATHOLOGY 2004; 5:409-423. [PMID: 20565617 DOI: 10.1111/j.1364-3703.2004.00241.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
SUMMARY We previously isolated a partial soybean cDNA clone (D17.1) whose corresponding transcript increases in susceptible roots 1 day post inoculation (dpi) with the soybean cyst nematode, Heterodera glycines. Here we isolated the corresponding full-length cDNA from a soybean cDNA library and designated this gene of unknown function Gm17.1. Time course RNA gel blot analyses revealed that Gm17.1 mRNA steady-state levels were elevated in soybean roots following H. glycines infection up to at least 6 dpi. For further in-depth study we identified a homologous Arabidopsis thaliana gene and designated this gene At17.1. Arabidopsis is successfully infected by the sugar beet cyst nematode (H. schachtii), a close relative of H. glycines. We isolated the At17.1 promoter, fused it to the beta-glucuronidase (GUS) reporter gene, and transformed this construct into Arabidopsis plants as well as soybean hairy roots. Histochemical analysis of plant materials containing the At17.1::GUS construct revealed that the At17.1 promoter is functional in Arabidopsis as well as in soybean and that during normal plant development the At17.1 promoter directs GUS expression predominantly to the vascular tissues and root tips of both plant species. When At17.1::GUS Arabidopsis plants and soybean hairy roots were inoculated with cyst nematodes, strong GUS activity was detected within the cyst nematode-induced feeding structures. Further tests of At17.1 promoter activity in Arabidopsis revealed that this promoter was induced by auxin, jasmonic acid, mannitol and dehydration. Quantitative real-time reverse transcription-polymerase chain reaction assays of At17.1 expression confirmed the observed promoter characteristics. Based on our expression data and the observation that both the soybean and the Arabidopsis homologues behaved in a similar fashion following cyst nematode infection, it is likely that these genes are closely associated with cyst nematode parasitism of plants, potentially with hormone and osmotic changes occurring in the developing nematode feeding cells. Furthermore, these data provide additional insights into the strengths of the Arabidopsis-H. schachtii pathosystem to study cyst nematode-plant interactions in lieu of less tractable pathosystems. This finding is supported by the fact that the Arabidopsis promoter tested here produced similar results in Arabidopsis and soybean.
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Affiliation(s)
- Mitra Mazarei
- Department of Plant Pathology, Iowa State University, Bessey Hall, Ames, IA 50011, USA
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Komarnytsky S, Borisjuk N. Functional analysis of promoter elements in plants. GENETIC ENGINEERING 2004; 25:113-41. [PMID: 15260236 DOI: 10.1007/978-1-4615-0073-5_6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
Affiliation(s)
- Slavko Komarnytsky
- Biotech Center, Cook College, Rutgers University, 59 Dudley Rd., New Brunswick, NJ 08901-8520, USA
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35
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Schreiber DN, Bantin J, Dresselhaus T. The MADS box transcription factor ZmMADS2 is required for anther and pollen maturation in maize and accumulates in apoptotic bodies during anther dehiscence. PLANT PHYSIOLOGY 2004; 134:1069-79. [PMID: 15001699 PMCID: PMC389931 DOI: 10.1104/pp.103.030577] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2003] [Revised: 08/22/2003] [Accepted: 12/12/2003] [Indexed: 05/19/2023]
Abstract
The maize (Zea mays) late pollen gene ZmMADS2 belongs to the MIKC type of MADS box transcription factor genes. Here, we report that ZmMADS2, which forms a homodimer in yeast (Saccharomyces cerevisiae), is required for anther dehiscence and pollen maturation. Development of anthers and pollen was arrested at 1 d before dehiscence in transgenic plants expressing the ZmMADS2-cDNA in antisense orientation. Temporal and spatial expression analyses showed high amounts of ZmMADS2 transcripts in endothecium and connective tissues of the anther at 1 d before dehiscence and in mature pollen after dehiscence. Transient transformation of maize and tobacco (Nicotiana tabacum) pollen with the luciferase reporter gene under the control of different ZmMADS2 promoter deletion constructs demonstrated the functionality and tissue specificity of the promoter. Transgenic maize plants expressing a ZmMADS2-green fluorescent protein fusion protein under control of the ZmMADS2 promoter were used to monitor protein localization during anther maturation and pollen tube growth. High amounts of the fusion protein accumulate in degenerating nuclei of endothecial and connective cells of the anther. A possible function of ZmMADS2 during anther dehiscence and pollen maturation and during pollen tube growth is discussed.
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Affiliation(s)
- Daniela N Schreiber
- Biocenter Klein Flottbek, Applied Plant Molecular Biology II, University of Hamburg, Ohnhorststrasse 18, D-22609 Hamburg, Germany
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Steffens NO, Galuschka C, Schindler M, Bülow L, Hehl R. AthaMap: an online resource for in silico transcription factor binding sites in the Arabidopsis thaliana genome. Nucleic Acids Res 2004; 32:D368-72. [PMID: 14681436 PMCID: PMC308752 DOI: 10.1093/nar/gkh017] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2003] [Revised: 09/04/2003] [Accepted: 09/04/2003] [Indexed: 11/14/2022] Open
Abstract
Gene expression is controlled mainly by the binding of transcription factors to regulatory sequences. To generate a genomic map for regulatory sequences, the Arabidopsis thaliana genome was screened for putative transcription factor binding sites. Using publicly available data from the TRANSFAC database and from publications, alignment matrices for 23 transcription factors of 13 different factor families were used with the pattern search program Patser to determine the genomic positions of more than 2.4 x 10(6) putative binding sites. Due to the dense clustering of genes and the observation that regulatory sequences are not restricted to upstream regions, the prediction of binding sites was performed for the whole genome. The genomic positions and the underlying data were imported into the newly developed AthaMap database. This data can be accessed by positional information or the Arabidopsis Genome Initiative identification number. Putative binding sites are displayed in the defined region. Data on the matrices used and on the thresholds applied in these screens are given in the database. Considering the high density of sites it will be a valuable resource for generating models on gene expression regulation. The data are available at http://www.athamap.de.
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Affiliation(s)
- Nils Ole Steffens
- Institut für Genetik, Technische Universität Braunschweig, Spielmannstrasse 7, D-38106 Braunschweig, Germany
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Patzlaff A, McInnis S, Courtenay A, Surman C, Newman LJ, Smith C, Bevan MW, Mansfield S, Whetten RW, Sederoff RR, Campbell MM. Characterisation of a pine MYB that regulates lignification. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2003; 36:743-54. [PMID: 14675440 DOI: 10.1046/j.1365-313x.2003.01916.x] [Citation(s) in RCA: 208] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
A member of the R2R3-MYB family of transcription factors was cloned from a cDNA library constructed from RNA isolated from differentiating pine xylem. This MYB, Pinus taeda MYB4 (PtMYB4), is expressed in cells undergoing lignification, as revealed by in situ RT-PCR. Electrophoretic mobility shift assays (EMSAs) showed that recombinant PtMYB4 protein is able to bind to DNA motifs known as AC elements. AC elements are ubiquitous in the promoters of genes encoding lignin biosynthetic enzymes. Transcriptional activation assays using yeast showed that PtMYB4 could activate transcription in an AC-element-dependent fashion. Overexpression of PtMYB4 in transgenic tobacco plants altered the accumulation of transcripts corresponding to genes encoding lignin biosynthetic enzymes. Lignin deposition increased in transgenic tobacco plants that overexpressed PtMYB4, and extended to cell types that do not normally lignify. Taken together, these findings are consistent with the hypothesis that PtMYB4 is sufficient to induce lignification, and that it may play this role during wood formation in pine.
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Affiliation(s)
- Astrid Patzlaff
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK
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Higginson T, Li SF, Parish RW. AtMYB103 regulates tapetum and trichome development in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2003; 35:177-92. [PMID: 12848824 DOI: 10.1046/j.1365-313x.2003.01791.x] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The AtMYB103 gene is a member of the R2R3 MYB gene family in Arabidopsis thaliana. Using the GUS reporter gene, AtMYB103 expression was found to be restricted to the tapetum of developing anthers. Employing RT-PCR and in situ hybridisation, we now show that AtMYB103 is also expressed in trichomes. GUS expression in trichomes was obtained by incorporating the coding and 3'-untranslated regions of AtMYB103 into the promoter-GUS constructs. Sense and antisense technologies were used to downregulate AtMYB103 expression. In transgenic lines with reduced AtMYB103 transcript levels, pollen, tapetum and trichome development were altered. The majority of the pollen grains were distorted in shape and had reduced or no cytoplasmic content. Tapetal degeneration occurred early, and large opaque bodies appeared in the tapetal cytoplasm. In transgenic plants, trichomes on cauline and rosette leaves produced additional branches. These overbranched trichomes contained more nuclear DNA than the wild-type trichomes. The results indicate that AtMYB103 is required for tapetal development and microsporogenesis, and negatively regulates trichome endoreduplication linked to the trichome branching.
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Affiliation(s)
- Trudi Higginson
- Department of Botany, La Trobe University, Bundoora Campus, Bundoora, Victoria 3083, Australia
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Thurau T, Kifle S, Jung C, Cai D. The promoter of the nematode resistance gene Hs1pro-1 activates a nematode-responsive and feeding site-specific gene expression in sugar beet (Beta vulgaris L.) and Arabidopsis thaliana. PLANT MOLECULAR BIOLOGY 2003; 52:643-660. [PMID: 12956533 DOI: 10.1023/a:1024887516581] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The Hs1pro-1 gene confers resistance to the beet cyst nematode Heterodera schachtii in sugar beet (Beta vulgaris L.) on the basis of a gene-for-gene relationship. RNA-gel blot analysis revealed that the transcript of Hs1pro-1 was present in uninfected roots of resistant beet at low levels but increased by about fourfold one day after nematode infection. Treatments of plants with external stimuli including salicylic acid, jasmonic acid, gibberellic acid and abscisic acid as well as wounding or salt stress did not result in changes in the gene transcription, indicating de novo transcription of Hs1pro-1 upon nematode infection specifically. To study transcriptional regulation of Hs1pro-1 expression at the cellular level, a 3082 bp genomic fragment representing the Hs1pro-1 promoter, isolated from the YAC-DNA housing the Hs1pro-1 gene, was fused to the beta-glucuronidase reporter gene (1832prm1::GUS) and transformed into susceptible beet roots and Arabidopsis plants, respectively. Fluorometric and histochemical GUS assays on transgenic beet roots and Arabidopsis plants carrying the 1832prm1::GUS construct demonstrated that the Hs1pro-1 promoter is functional in both species and drives a nematode responsive and feeding site-specific GUS-expression. GUS activity was detected as early as at initiation of the nematode feeding sites and GUS staining was restricted to the nematode feeding sites. To delineate the regulatory domains of the Hs1pro-1 promoter, fusion genes with various 5' deletions of the Hs1pro-1 promoter and the GUS gene were constructed and analysed in transgenic beet roots as well. Cis elements responsible for feeding site-specific gene expression reside between -355 and +247 from the transcriptional initiation site of Hs1pro-1 whereas an enhancer region necessary for higher gene expression is located between -1199 and -705 of the promoter. The Hs1pro-1 promoter drives a nematode feeding site-specific GUS expression in both sugar beet and Arabidopsis suggesting a conserved mechanism of regulation of Hs1pro-1 expression in these two species.
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Affiliation(s)
- Tim Thurau
- Institute of Crop Science and Plant Breeding, Christian Albrechts University of Kiel, Olshausenstrasse 40, 24098 Kiel, Germany
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Abstract
Pollen plays a critical role in the life cycle of all flowering plants, generating a polarized pollen tube that delivers sperm to the eggs in the interior of the flower. Pollen tubes perceive multiple extracellular signals during their extended growth through different floral environments; these environments discriminate among pollen grains, allowing only those that are appropriately recognized to invade. The phases of pollen tube growth include interactions that establish pollen polarity, entry of pollen tubes into female cell walls, and adhesion-based pollen tube motility through a carbohydrate-rich matrix. Recent studies have identified cells within the female germ unit as important sources of pollen guidance cues. Other signals undoubtedly exist, and their discovery will require genetic screens that target diploid tissues as well as haploid male and female cells.
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Affiliation(s)
- Mark A Johnson
- Department of Molecular Genetics and Cell Biology, Howard Hughes Medical Institute, The University of Chicago, 1103 East 57th Street, Chicago, IL 60637, USA
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