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Ye X, Sun J, Tian Y, Chen J, Yao X, Quan X, Huang L. Identification of YUC genes associated with leaf wrinkling trait in Tacai variety of Chinese cabbage. PeerJ 2024; 12:e17337. [PMID: 38784401 PMCID: PMC11114110 DOI: 10.7717/peerj.17337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 04/15/2024] [Indexed: 05/25/2024] Open
Abstract
Chinese cabbage (Brassica campestris L. ssp. chinensis (L.) Makino) stands as a widely cultivated leafy vegetable in China, with its leaf morphology significantly influencing both quality and yield. Despite its agricultural importance, the precise mechanisms governing leaf wrinkling development remain elusive. This investigation focuses on 'Wutacai', a representative cultivar of the Tacai variety (Brassica campestris L. ssp. chinensis var. rosularis Tsen et Lee), renowned for its distinct leaf wrinkling characteristics. Within the genome of 'Wutacai', we identified a total of 18 YUCs, designated as BraWTC_YUCs, revealing their conservation within the Brassica genus, and their close homology to YUCs in Arabidopsis. Expression profiling unveiled that BraWTC_YUCs in Chinese Cabbage exhibited organ-specific and leaf position-dependent variation. Additionally, transcriptome sequencing data from the flat leaf cultivar 'Suzhouqing' and the wrinkled leaf cultivar 'Wutacai' revealed differentially expressed genes (DEGs) related to auxin during the early phases of leaf development, particularly the YUC gene. In summary, this study successfully identified the YUC gene family in 'Wutacai' and elucidated its potential function in leaf wrinkling trait, to provide valuable insights into the prospective molecular mechanisms that regulate leaf wrinkling in Chinese cabbage.
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Affiliation(s)
- Xuelian Ye
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Ji Sun
- College of Agriculture and Biotechnology, Wenzhou Vocational College of Science and Technology (Wenzhou Academy of Agricultural Sciences), Wenzhou, China
| | - Yuan Tian
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Jingwen Chen
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Xiangtan Yao
- Jiaxing Academy of Agricultural Sciences, Jiaxing, China
| | - Xinhua Quan
- Jiaxing Academy of Agricultural Sciences, Jiaxing, China
| | - Li Huang
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
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2
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Vondracek K, Altpeter F, Liu T, Lee S. Advances in genomics and genome editing for improving strawberry ( Fragaria ×ananassa). Front Genet 2024; 15:1382445. [PMID: 38706796 PMCID: PMC11066249 DOI: 10.3389/fgene.2024.1382445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 04/04/2024] [Indexed: 05/07/2024] Open
Abstract
The cultivated strawberry, Fragaria ×ananassa, is a recently domesticated fruit species of economic interest worldwide. As such, there is significant interest in continuous varietal improvement. Genomics-assisted improvement, including the use of DNA markers and genomic selection have facilitated significant improvements of numerous key traits during strawberry breeding. CRISPR/Cas-mediated genome editing allows targeted mutations and precision nucleotide substitutions in the target genome, revolutionizing functional genomics and crop improvement. Genome editing is beginning to gain traction in the more challenging polyploid crops, including allo-octoploid strawberry. The release of high-quality reference genomes and comprehensive subgenome-specific genotyping and gene expression profiling data in octoploid strawberry will lead to a surge in trait discovery and modification by using CRISPR/Cas. Genome editing has already been successfully applied for modification of several strawberry genes, including anthocyanin content, fruit firmness and tolerance to post-harvest disease. However, reports on many other important breeding characteristics associated with fruit quality and production are still lacking, indicating a need for streamlined genome editing approaches and tools in Fragaria ×ananassa. In this review, we present an overview of the latest advancements in knowledge and breeding efforts involving CRISPR/Cas genome editing for the enhancement of strawberry varieties. Furthermore, we explore potential applications of this technology for improving other Rosaceous plant species.
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Affiliation(s)
- Kaitlyn Vondracek
- Gulf Coast Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Wimauma, FL, United States
- University of Florida, Horticultural Sciences Department, Institute of Food and Agricultural Sciences, Gainesville, FL, United States
| | - Fredy Altpeter
- University of Florida, Agronomy Department, Institute of Food and Agricultural Sciences, Gainesville, FL, United States
| | - Tie Liu
- University of Florida, Horticultural Sciences Department, Institute of Food and Agricultural Sciences, Gainesville, FL, United States
| | - Seonghee Lee
- Gulf Coast Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Wimauma, FL, United States
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3
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Lu R, Pi M, Liu Z, Kang C. Auxin biosynthesis gene FveYUC4 is critical for leaf and flower morphogenesis in woodland strawberry. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 115:1428-1442. [PMID: 37248638 DOI: 10.1111/tpj.16333] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/14/2023] [Accepted: 05/23/2023] [Indexed: 05/31/2023]
Abstract
Auxin plays an essential role in plant growth and development, particularly in fruit development. The YUCCA (YUC) genes encode flavin monooxygenases that catalyze a rate-limiting step in auxin biosynthesis. Mutations that disrupt YUC gene function provide useful tools for dissecting general and specific functions of auxin during plant development. In woodland strawberry (Fragaria vesca), two ethyl methanesulfonate mutants, Y422 and Y1011, have been identified that exhibit severe defects in leaves and flowers. In particular, the width of the leaf blade is greatly reduced, and each leaflet in the mutants has fewer and deeper serrations. In addition, the number and shape of the floral organs are altered, resulting in smaller fruits. Mapping by sequencing revealed that both mutations reside in the FveYUC4 gene, and were therefore renamed as yuc4-1 and yuc4-2. Consistent with a role for FveYUC4 in auxin synthesis, free auxin and its metabolites are significantly reduced in the yuc4 leaves and flowers. This role of FveYUC4 in leaf and flower development is supported by its high and specific expression in young leaves and flower buds using GUS reporters. Furthermore, germline transformation of pYUC4::YUC4, which resulted in elevated expression of FveYUC4 in yuc4 mutants, not only rescued the leaf and flower defects but also produced parthenocarpic fruits. Taken together, our data demonstrate that FveYUC4 is essential for leaf and flower morphogenesis in woodland strawberry by providing auxin hormone at the proper time and in the right tissues.
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Affiliation(s)
- Rui Lu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Mengting Pi
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Zhongchi Liu
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, 20742, USA
| | - Chunying Kang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
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4
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Solanki M, Shukla LI. Recent advances in auxin biosynthesis and homeostasis. 3 Biotech 2023; 13:290. [PMID: 37547917 PMCID: PMC10400529 DOI: 10.1007/s13205-023-03709-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 07/18/2023] [Indexed: 08/08/2023] Open
Abstract
The plant proliferation is linked with auxins which in turn play a pivotal role in the rate of growth. Also, auxin concentrations could provide insights into the age, stress, and events leading to flowering and fruiting in the sessile plant kingdom. The role in rejuvenation and plasticity is now evidenced. Interest in plant auxins spans many decades, information from different plant families for auxin concentrations, transcriptional, and epigenetic evidences for gene regulation is evaluated here, for getting an insight into pattern of auxin biosynthesis. This biosynthesis takes place via an tryptophan-independent and tryptophan-dependent pathway. The independent pathway initiated before the tryptophan (trp) production involves indole as the primary substrate. On the other hand, the trp-dependent IAA pathway passes through the indole pyruvic acid (IPyA), indole-3-acetaldoxime (IAOx), and indole acetamide (IAM) pathways. Investigations on trp-dependent pathways involved mutants, namely yucca (1-11), taa1, nit1, cyp79b and cyp79b2, vt2 and crd, and independent mutants of tryptophan, ins are compiled here. The auxin conjugates of the IAA amide and ester-linked mutant gh3, iar, ilr, ill, iamt1, ugt, and dao are remarkable and could facilitate the assimilation of auxins. Efforts are made herein to provide an up-to-date detailed information about biosynthesis leading to plant sustenance. The vast information about auxin biosynthesis and homeostasis is consolidated in this review with a simplified model of auxin biosynthesis with keys and clues for important missing links since auxins can enable the plants to proliferate and override the environmental influence and needs to be probed for applications in sustainable agriculture. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-023-03709-6.
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Affiliation(s)
- Manish Solanki
- Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Pondicherry, 605014 India
- Puducherry, India
| | - Lata Israni Shukla
- Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Pondicherry, 605014 India
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Luo W, Xiao N, Wu F, Mo B, Kong W, Yu Y. Genome-Wide Identification and Characterization of YUCCA Gene Family in Mikania micrantha. Int J Mol Sci 2022; 23:13037. [PMID: 36361840 PMCID: PMC9655643 DOI: 10.3390/ijms232113037] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/21/2022] [Accepted: 10/24/2022] [Indexed: 09/28/2023] Open
Abstract
Auxin is a general coordinator for growth and development throughout plant lifespan, acting in a concentration-dependent manner. Tryptophan aminotransferases (YUCCA) family catalyze the oxidative decarboxylation of indole-3-pyruvic acid (IPA) to form indole-3-acetic acid (IAA) and plays a critical role in auxin homeostasis. Here, 18 YUCCA family genes divided into four categories were identified from Mikania micrantha (M. micrantha), one of the world's most invasive plants. Five highly conserved motifs were characterized in these YUCCA genes (MmYUCs). Transcriptome analysis revealed that MmYUCs exhibited distinct expression patterns in different organs and five MmYUCs showed high expression levels throughout all the five tissues, implying that they may play dominant roles in auxin biosynthesis and plant development. In addition, MmYUC6_1 was overexpressed in DR5::GUS Arabidopsis line to explore its function, which resulted in remarkably increased auxin level and typical elevated auxin-related phenotypes including shortened roots and elongated hypocotyls in the transgenic plants, suggesting that MmYUC6_1 promoted IAA biosynthesis in Arabidopsis. Collectively, these findings provided comprehensive insight into the phylogenetic relationships, chromosomal distributions, expression patterns and functions of the MmYUC genes in M. micrantha, which would facilitate the study of molecular mechanisms underlying the fast growth of M. micrantha and preventing its invasion.
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Affiliation(s)
- Weigui Luo
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Nian Xiao
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Feiyan Wu
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Beixin Mo
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Wenwen Kong
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Yu Yu
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
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6
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Roles of Auxin in the Growth, Development, and Stress Tolerance of Horticultural Plants. Cells 2022; 11:cells11172761. [PMID: 36078168 PMCID: PMC9454831 DOI: 10.3390/cells11172761] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/29/2022] [Accepted: 08/29/2022] [Indexed: 12/04/2022] Open
Abstract
Auxin, a plant hormone, regulates virtually every aspect of plant growth and development. Many current studies on auxin focus on the model plant Arabidopsis thaliana, or on field crops, such as rice and wheat. There are relatively few studies on what role auxin plays in various physiological processes of a range of horticultural plants. In this paper, recent studies on the role of auxin in horticultural plant growth, development, and stress response are reviewed to provide novel insights for horticultural researchers and cultivators to improve the quality and application of horticultural crops.
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Liang J, Wu Z, Xu T, Li X, Jiang F, Wang H. Overexpression of HANABA TARANU in cultivated strawberry delays flowering and leads to defective flower and fruit development. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 321:111307. [PMID: 35696907 DOI: 10.1016/j.plantsci.2022.111307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 03/14/2022] [Accepted: 04/28/2022] [Indexed: 06/15/2023]
Abstract
Cultivated strawberry is one of the most important horticultural crops in the world, and the fruit yields and economic benefits are largely dependent on the quality of floral initiation and floral organ development. However, the underlying regulatory mechanisms controlling these processes in strawberry are largely unknown. In this study, the function of a GATA transcription factor gene, HANABA TARANU (HAN), in floral initiation and floral organ development was characterized in strawberry. FaHAN is expressed in four whorls of the floral organs. Overexpression (OE) of FaHAN in the strawberry cultivar 'Benihoppe' delayed flowering by at least one week by affecting key genes, such as TERMINAL FLOWER 1, APETALA 1…and increased the number of runners. FaHAN-OE plants also showed malformed floral organs, especially the deformed stigmas with disordered arrangement. Several key genes for pistil apical development such as STYLISH, YUCCA 1, and auxin-related genes such as GH3.5, PIN-FORMED 1, which play important roles in pistil primordium development in many plant species, were all down-regulated in FaHAN-OE plants. Further observations showed that the fruit deformity rate was nearly 4-fold higher than in control plants. Together, this study provides a new approach for exploring floral initiation and floral organ development in strawberry.
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Affiliation(s)
- Jiahui Liang
- College of Horticulture, China Agricultural University, Beijing 100193, PR China
| | - Ze Wu
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Tengfei Xu
- College of Horticulture, China Agricultural University, Beijing 100193, PR China
| | - Xiaofeng Li
- College of Horticulture, China Agricultural University, Beijing 100193, PR China
| | - Feng Jiang
- College of Horticulture, China Agricultural University, Beijing 100193, PR China
| | - Hongqing Wang
- College of Horticulture, China Agricultural University, Beijing 100193, PR China.
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CkREV Enhances the Drought Resistance of Caragana korshinskii through Regulating the Expression of Auxin Synthetase Gene CkYUC5. Int J Mol Sci 2022; 23:ijms23115902. [PMID: 35682582 PMCID: PMC9180416 DOI: 10.3390/ijms23115902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/21/2022] [Accepted: 05/23/2022] [Indexed: 12/14/2022] Open
Abstract
As a common abiotic stress, drought severely impairs the growth, development, and even survival of plants. Here we report a transcription factor, Caragana korshinskii REVOLUTA(CkREV), which can bidirectionally regulate the expression of the critical enzyme gene CkYUC5 in auxin synthesis according to external environment changes, so as to control the biosynthesis of auxin and further enhance the drought resistance of plants. Quantitative analysis reveals that the expression level of both CkYUC5 and AtYUC5 is down-regulated after C. korshinskii and Arabidopsis thaliana are exposed to drought. Functional verification of CkREV reveals that CkREV up-regulates the expression of AtYUC5 in transgenic A. thaliana under common conditions, while down-regulating it under drought conditions. Meanwhile, the expression of CkYUC5 is also down-regulated in C. korshinskii leaves instantaneously overexpressing CkREV. We apply a dual-luciferase reporter system to discover that CkREV can bind to the promoter of CkYUC5 to regulate its expression, which is further proved by EMSA and Y1H esxperiments. Functional verification of CkREV in C. korshinskii and transgenic A. thaliana shows that CkREV can regulate the expression of CkYUC5 and AtYUC5 in a contrary way, maintaining the equilibrium of plants between growth and drought resisting. CkREV can positively regulate the expression of CkYUC5 to promote auxin synthesis in favor of growth under normal development. However, CkREV can also respond to external signals and negatively regulate the expression of CkYUC5, which inhibits auxin synthesis in order to reduce growth rate, lower water demands, and eventually improve the drought resistance of plants.
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Yang Y, Xu T, Wang H, Feng D. Genome-wide identification and expression analysis of the TaYUCCA gene family in wheat. Mol Biol Rep 2021; 48:1269-1279. [PMID: 33547532 DOI: 10.1007/s11033-021-06197-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 01/28/2021] [Indexed: 11/29/2022]
Abstract
Auxin is an important endogenous hormone in plants. The YUCCA gene encodes a flavin monooxygenase, which is an important rate-limiting enzyme in the auxin synthesis pathway and involved in the regulation of plant growth and development. In the study, we identified 63 wheat TaYUCCA genes; among them, some genes appeared in clusters. By constructing phylogenetic trees, we found that the TaYUCCA genes could be divided into six groups. In the WheatExp database, there were 22 differential expressed TaYUCCA genes, among which the TaYUCCA10 gene was abundantly expressed in the endosperm and medium milk stage, the TaYUCCA2 gene was abundantly expressed in the roots of three leaves and meiosis and transfer cells at 20 days post anthesis and the others 16 TaYUCCA genes had different expression level at different developmental stages in wheat, and there were 15 TaYUCCA genes induced by drought and heat stress, among which the TaYUCCA2-D, TaYUCCA3-B, and TaYUCCA9-D might be upregulated induced by drought stress, TaYUCCA10.1 might be upregulated induced drought and heat stress, TaYUCCA6-A was upregulated induced both drought and heat stress and the others 9 TaYUCCA genes were downregulated induced by drought and heat stress. Transcriptome and qRT-PCR analysis showed that TaYUCCA7-A was upregulated significantly after induced by powdery mildew. The comprehensive annotation and expression profiling of the TaYUCCA genes in this study enhanced our understanding of TaYUCCA family gene expression in wheat growth and development and laid the foundation for the further study of TaYUCCA gene mechanism.
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Affiliation(s)
- Yanlin Yang
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Tian Xu
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Honggang Wang
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Deshun Feng
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an, 271018, Shandong, China.
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10
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Genome-wide identification and expression profiling of the YUCCA gene family in Malus domestica. Sci Rep 2020; 10:10866. [PMID: 32616911 PMCID: PMC7331580 DOI: 10.1038/s41598-020-66483-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 03/31/2020] [Indexed: 12/20/2022] Open
Abstract
The plant hormone auxin is essential for plant growth and development. YUCCA proteins catalyse the rate-limiting step for endogenous auxin biosynthesis. In this study, we isolated 20 MdYUCCA genes from apple genome. MdYUCCA6a, MdYUCCA8a, and MdYUCCA10a were expressed in most organs and could support whole plant basal auxin synthesis. MdYUCCA4a, MdYUCCA10b, and MdYUCCA11a expression indicated roles for these genes in auxin biosynthesis in vegetative organs. MdYUCCA2b, MdYUCCA11b, and MdYUCCA11d were mainly expressed in flower organs. High temperature induced the expression of MdYUCCA4a, MdYUCCA6a, MdYUCCA8a, and MdYUCCA10a, and down-regulated the expression of MdYUCCA2b and MdYUCCA6b. Dual-luciferase assay indicated that MdPIF4 could trans-activate the MdYUCCA8a promoter. Overexpression of MdYUCCA8a increased IAA content, increased stem height, enhanced apical dominance, and led to silique malformation. These results provide a foundation for further investigation of the biological functions of apple MdYUCCAs.
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Qin M, Wang J, Zhang T, Hu X, Liu R, Gao T, Zhao S, Yuan Y, Zheng J, Wang Z, Wei X, Li T. Genome-Wide Identification and Analysis on YUCCA Gene Family in Isatis indigotica Fort. and IiYUCCA6-1 Functional Exploration. Int J Mol Sci 2020; 21:ijms21062188. [PMID: 32235744 PMCID: PMC7139497 DOI: 10.3390/ijms21062188] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/15/2020] [Accepted: 03/19/2020] [Indexed: 01/02/2023] Open
Abstract
Auxin is one of the most critical hormones in plants. YUCCA (Tryptophan aminotransferase of Arabidopsis (TAA)/YUCCA) enzymes catalyze the key rate-limiting step of the tryptophan-dependent auxin biosynthesis pathway, from IPA (Indole-3-pyruvateacid) to IAA (Indole-3-acetic acid). Here, 13 YUCCA family genes were identified from Isatis indigotica, which were divided into four categories, distributing randomly on chromosomes (2n = 14). The typical and conservative motifs, including the flavin adenine dinucleotide (FAD)-binding motif and flavin-containing monooxygenases (FMO)-identifying sequence, existed in the gene structures. IiYUCCA genes were expressed differently in different organs (roots, stems, leaves, buds, flowers, and siliques) and developmental periods (7, 21, 60, and 150 days after germination). Taking IiYUCCA6-1 as an example, the YUCCA genes functions were discussed. The results showed that IiYUCCA6-1 was sensitive to PEG (polyethylene glycol), cold, wounding, and NaCl treatments. The over-expressed tobacco plants exhibited high auxin performances, and some early auxin response genes (NbIAA8, NbIAA16, NbGH3.1, and NbGH3.6) were upregulated with increased IAA content. In the dark, the contents of total chlorophyll and hydrogen peroxide in the transgenic lines were significantly lower than in the control group, with NbSAG12 downregulated and some delayed leaf senescence characteristics, which delayed the senescence process to a certain extent. The findings provide comprehensive insight into the phylogenetic relationships, chromosomal distributions, and expression patterns and functions of the YUCCA gene family in I. indigotica.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Tao Li
- Correspondence: ; Tel.: +86-29-85310266
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12
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The Roles of Auxin Biosynthesis YUCCA Gene Family in Plants. Int J Mol Sci 2019; 20:ijms20246343. [PMID: 31888214 PMCID: PMC6941117 DOI: 10.3390/ijms20246343] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 12/10/2019] [Accepted: 12/12/2019] [Indexed: 12/16/2022] Open
Abstract
Auxin plays essential roles in plant normal growth and development. The auxin signaling pathway relies on the auxin gradient within tissues and cells, which is facilitated by both local auxin biosynthesis and polar auxin transport (PAT). The TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS (TAA)/YUCCA (YUC) pathway is the most important and well-characterized pathway that plants deploy to produce auxin. YUCs function as flavin-containing monooxygenases (FMO) catalyzing the rate-limiting irreversible oxidative decarboxylation of indole-3-pyruvate acid (IPyA) to form indole-3-acetic acid (IAA). The spatiotemporal dynamic expression of different YUC gene members finely tunes the local auxin biosynthesis in plants, which contributes to plant development as well as environmental responses. In this review, the recent advances in the identification, evolution, molecular structures, and functions in plant development and stress response regarding the YUC gene family are addressed.
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13
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Feng J, Dai C, Luo H, Han Y, Liu Z, Kang C. Reporter gene expression reveals precise auxin synthesis sites during fruit and root development in wild strawberry. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:563-574. [PMID: 30371880 PMCID: PMC6322568 DOI: 10.1093/jxb/ery384] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 10/18/2018] [Indexed: 05/18/2023]
Abstract
The critical role of auxin in strawberry fruit set and receptacle enlargement was demonstrated previously. While fertilization is known to trigger auxin biosynthesis, the specific tissue source of fertilization-induced auxin is not well understood. Here, the auxin reporter DR5ver2::GUS was introduced into wild strawberry (Fragaria vesca) to reveal auxin distribution in the seed and fruit receptacle pre- and post-fertilization as well as in the root. In addition, the expression of TAR and YUCCA genes coding for enzymes catalysing the two-step auxin biosynthesis pathway was investigated using their respective promoters fused to the β-glucuronidase (GUS) reporter. Two FveTARs and four FveYUCs were shown to be expressed primarily in the endosperm and embryo inside the achenes as well as in root tips and lateral root primordia. Expression of these reporters in dissected tissues provided more detailed and precise spatial (cell and tissue) and temporal (pre- and post-fertilization) information on where auxin is synthesized and accumulates than previous studies in strawberry. Moreover, we generated CRISPR-mediated knock-out mutants of FveYUC10, the most abundant YUC in seeds; the mutants had a lower free auxin level in young fruit, but displayed no obvious morphological phenotypes. However, overexpression of FveYUC10 resulted in elongated hypocotyls in Arabidopsis caused by elevated auxin level. Overall, the study revealed auxin accumulation in the chalazal seed coat, embryo, receptacle vasculature, root tip, and lateral root primordia and highlighted the endosperm as the main auxin biosynthesis site for fruit set.
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Affiliation(s)
- Jia Feng
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China
| | - Cheng Dai
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Huifeng Luo
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China
| | - Yafan Han
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China
| | - Zhongchi Liu
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - Chunying Kang
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China
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Zhao Y. Essential Roles of Local Auxin Biosynthesis in Plant Development and in Adaptation to Environmental Changes. ANNUAL REVIEW OF PLANT BIOLOGY 2018; 69:417-435. [PMID: 29489397 DOI: 10.1146/annurev-arplant-042817-040226] [Citation(s) in RCA: 151] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
It has been a dominant dogma in plant biology that the self-organizing polar auxin transport system is necessary and sufficient to generate auxin maxima and minima that are essential for almost all aspects of plant growth and development. However, in the past few years, it has become clear that local auxin biosynthesis is required for a suite of developmental processes, including embryogenesis, endosperm development, root development, and floral initiation and patterning. Moreover, it was discovered that local auxin biosynthesis maintains optimal plant growth in response to environmental signals, including light, temperature, pathogens, and toxic metals. In this article, I discuss the recent progress in auxin biosynthesis research and the paradigm shift in recognizing the important roles of local auxin biosynthesis in plant biology.
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Affiliation(s)
- Yunde Zhao
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California 92093, USA;
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15
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Malka SK, Cheng Y. Possible Interactions between the Biosynthetic Pathways of Indole Glucosinolate and Auxin. FRONTIERS IN PLANT SCIENCE 2017; 8:2131. [PMID: 29312389 PMCID: PMC5735125 DOI: 10.3389/fpls.2017.02131] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 11/30/2017] [Indexed: 05/21/2023]
Abstract
Glucosinolates (GLS) are a group of plant secondary metabolites mainly found in Cruciferous plants, share a core structure consisting of a β-thioglucose moiety and a sulfonated oxime, but differ by a variable side chain derived from one of the several amino acids. These compounds are hydrolyzed upon cell damage by thioglucosidase (myrosinase), and the resulting degradation products are toxic to many pathogens and herbivores. Human beings use these compounds as flavor compounds, anti-carcinogens, and bio-pesticides. GLS metabolism is complexly linked to auxin homeostasis. Indole GLS contributes to auxin biosynthesis via metabolic intermediates indole-3-acetaldoxime (IAOx) and indole-3-acetonitrile (IAN). IAOx is proposed to be a metabolic branch point for biosynthesis of indole GLS, IAA, and camalexin. Interruption of metabolic channeling of IAOx into indole GLS leads to high-auxin production in GLS mutants. IAN is also produced as a hydrolyzed product of indole GLS and metabolized to IAA by nitrilases. In this review, we will discuss current knowledge on involvement of GLS in auxin homeostasis.
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Affiliation(s)
- Siva K. Malka
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Youfa Cheng
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- School of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
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16
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Li T, Wang J, Lu M, Zhang T, Qu X, Wang Z. Selection and Validation of Appropriate Reference Genes for qRT-PCR Analysis in Isatis indigotica Fort. FRONTIERS IN PLANT SCIENCE 2017; 8:1139. [PMID: 28702046 PMCID: PMC5487591 DOI: 10.3389/fpls.2017.01139] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 06/13/2017] [Indexed: 05/29/2023]
Abstract
Due to its sensitivity and specificity, real-time quantitative PCR (qRT-PCR) is a popular technique for investigating gene expression levels in plants. Based on the Minimum Information for Publication of Real-Time Quantitative PCR Experiments (MIQE) guidelines, it is necessary to select and validate putative appropriate reference genes for qRT-PCR normalization. In the current study, three algorithms, geNorm, NormFinder, and BestKeeper, were applied to assess the expression stability of 10 candidate reference genes across five different tissues and three different abiotic stresses in Isatis indigotica Fort. Additionally, the IiYUC6 gene associated with IAA biosynthesis was applied to validate the candidate reference genes. The analysis results of the geNorm, NormFinder, and BestKeeper algorithms indicated certain differences for the different sample sets and different experiment conditions. Considering all of the algorithms, PP2A-4 and TUB4 were recommended as the most stable reference genes for total and different tissue samples, respectively. Moreover, RPL15 and PP2A-4 were considered to be the most suitable reference genes for abiotic stress treatments. The obtained experimental results might contribute to improved accuracy and credibility for the expression levels of target genes by qRT-PCR normalization in I. indigotica.
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17
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Ke Q, Wang Z, Ji CY, Jeong JC, Lee HS, Li H, Xu B, Deng X, Kwak SS. Transgenic poplar expressing Arabidopsis YUCCA6 exhibits auxin-overproduction phenotypes and increased tolerance to abiotic stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2015; 94:19-27. [PMID: 25980973 DOI: 10.1016/j.plaphy.2015.05.003] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 05/04/2015] [Accepted: 05/08/2015] [Indexed: 05/04/2023]
Abstract
YUCCA6, a member of the YUCCA family of flavin monooxygenase-like proteins, is involved in the tryptophan-dependent IAA biosynthesis pathway and responses to environmental cues in Arabidopsis. However, little is known about the role of the YUCCA pathway in auxin biosynthesis in poplar. Here, we generated transgenic poplar (Populus alba × P. glandulosa) expressing the Arabidopsis YUCCA6 gene under the control of the oxidative stress-inducible SWPA2 promoter (referred to as SY plants). Three SY lines (SY7, SY12 and SY20) were selected based on the levels of AtYUCCA6 transcript. SY plants displayed auxin-overproduction morphological phenotypes, such as rapid shoot growth and retarded main root development with increased root hair formation. In addition, SY plants had higher levels of free IAA and early auxin-response gene transcripts. SY plants exhibited tolerance to drought stress, which was associated with reduced levels of reactive oxygen species. Furthermore, SY plants showed delayed hormone- and dark-induced senescence in detached leaves due to higher photosystem II efficiency and less membrane permeability. These results suggest that the conserved IAA biosynthesis pathway mediated by YUCCA family members exists in poplar.
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Affiliation(s)
- Qingbo Ke
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, South Korea; Department of Green Chemistry and Environmental Biotechnology, Korea University of Science and Technology, Daejeon 305-350, South Korea
| | - Zhi Wang
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Chang Yoon Ji
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, South Korea; Department of Green Chemistry and Environmental Biotechnology, Korea University of Science and Technology, Daejeon 305-350, South Korea
| | - Jae Cheol Jeong
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, South Korea; Department of Green Chemistry and Environmental Biotechnology, Korea University of Science and Technology, Daejeon 305-350, South Korea
| | - Haeng-Soon Lee
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, South Korea; Department of Green Chemistry and Environmental Biotechnology, Korea University of Science and Technology, Daejeon 305-350, South Korea
| | - Hongbing Li
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Bingcheng Xu
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Xiping Deng
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Sang-Soo Kwak
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, South Korea; Department of Green Chemistry and Environmental Biotechnology, Korea University of Science and Technology, Daejeon 305-350, South Korea.
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18
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Li W, Zhao X, Zhang X. Genome-Wide Analysis and Expression Patterns of the YUCCA Genes in Maize. J Genet Genomics 2015; 42:707-10. [PMID: 26743989 DOI: 10.1016/j.jgg.2015.06.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 06/09/2015] [Accepted: 06/13/2015] [Indexed: 10/23/2022]
Affiliation(s)
- Wenlan Li
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China
| | - Xiangyu Zhao
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China.
| | - Xiansheng Zhang
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China.
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19
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Isolation and characterization of three TaYUC10genes from wheat. Gene 2014; 546:187-94. [PMID: 24929126 DOI: 10.1016/j.gene.2014.06.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 06/09/2014] [Accepted: 06/10/2014] [Indexed: 12/30/2022]
Abstract
YUCCA protein participates in a key rate-limiting step in the tryptophan-dependent pathway for auxin biosynthesis and is involved in numerous processes during plant development. In this study, the genomic and cDNA sequences of three TaYUC10 homoeologous genes were isolated. These sequences showed a very high conservation in coding region and the exon/intron structure, whereas their intron lengths were different. The cDNA and polypeptide chains of the three TaYUC10 genes were highly similar. These genes were most homologous to BdYUC10. Location analysis showed that TaYUC10.1 was present in chromosome 5BL. TaYUC10.3 was expressed in all parts of the wheat, but was predominant in the reproductive organs of mature wheat, such as flowering spikelets or fertilized embryos. In the fertilized embryos 28d post-anthesis, expression of TaYUC10.3 was clearly increased with the development of seeds. This indicates that TaYUC genes may play a vital role in seed development. TaYUC10.3 overexpressed in Arabidopsis had a typical phenotype, excessive auxin accumulation also seen in higher plants, and showed increased spacing of silique and downward curling of the blade margin. Sterility was observed in adult transgenic plants, becoming more severe in late development. The floral structures of sterile plants were not integrated. TaYUC10 may be required for numerous wheat growth processes, including flower and seed development.
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Liu H, Xie WF, Zhang L, Valpuesta V, Ye ZW, Gao QH, Duan K. Auxin biosynthesis by the YUCCA6 flavin monooxygenase gene in woodland strawberry. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2014; 56:350-63. [PMID: 24373096 DOI: 10.1111/jipb.12150] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 12/13/2013] [Indexed: 05/08/2023]
Abstract
Auxin has been regarded as the main signal molecule coordinating the growth and ripening of fruits in strawberry, the reference genomic system for Rosaceae. The mechanisms regulating auxin biosynthesis in strawberry are largely elusive. Recently, we demonstrated that two YUCCA genes are involved in flower and fruit development in cultivated strawberry. Here, we show that the woodland strawberry (Fragaria vesca L.) genome harbors nine loci for YUCCA genes and eight of them encode functional proteins. Transcription pattern in different plant organs was different for all eight FvYUCs. Functionality of the FvYUC6 gene was studied in transgenic strawberry overexpressing FvYUC6, which showed typical high-auxin phenotypes. Overexpression of FvYUC6 also delayed flowering and led to complete male sterility in F. vesca. Additionally, specific repression of FvYUC6 expression by RNA interference significantly inhibited vegetative growth and reduced plant fertility. The development of leaves, roots, flowers, and fruits was greatly affected in FvYUC6-repressed plants. Expression of a subset of auxin-responsive genes was well correlated with the changes of FvYUC6 transcript levels and free indole-3-acetic acid levels in transgenic strawberry. These observations are consistent with an important role of FvYUC6 in auxin synthesis, and support a main role of the gene product in vegetative and reproductive development in woodland strawberry.
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Affiliation(s)
- Hong Liu
- Forestry and Fruit Tree Research Institute, Shanghai Key Laboratory of Protected Horticultural Technology, Shanghai Academy of Agricultural Sciences (SAAS), Shanghai, 201403, China; Shanghai Key Laboratory of Agricultural Genetics and Breeding, Institute of Biotechnology, SAAS, Shanghai, 201106, China
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21
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Abstract
lndole-3-acetic acid (IAA), the most important natural auxin in plants, is mainly synthesized from the amino acid tryptophan (Trp). Recent genetic and biochemical studies in Arabidopsis have unambiguously established the first complete Trp-dependent auxin biosynthesis pathway. The first chemical step of auxin biosynthesis is the removal of the amino group from Trp by the TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS (TAA) family of transaminases to generate indole-3-pyruvate (IPA). IPA then undergoes oxidative decarboxylation catalyzed by the YUCCA (YUC) family of flavin monooxygenases to produce IAA. This two-step auxin biosynthesis pathway is highly conserved throughout the plant kingdom and is essential for almost all of the major developmental processes. The successful elucidation of a complete auxin biosynthesis pathway provides the necessary tools for effectively modulating auxin concentrations in plants with temporal and spatial precision. The progress in auxin biosynthesis also lays a foundation for understanding polar auxin transport and for dissecting auxin signaling mechanisms during plant development.
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Affiliation(s)
- Yunde Zhao
- Section of Cell and Developmental Biology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116 Address correspondence to
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Böttcher C, Burbidge CA, Boss PK, Davies C. Interactions between ethylene and auxin are crucial to the control of grape (Vitis vinifera L.) berry ripening. BMC PLANT BIOLOGY 2013; 13:222. [PMID: 24364881 PMCID: PMC3878033 DOI: 10.1186/1471-2229-13-222] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 12/20/2013] [Indexed: 05/18/2023]
Abstract
BACKGROUND Fruit development is controlled by plant hormones, but the role of hormone interactions during fruit ripening is poorly understood. Interactions between ethylene and the auxin indole-3-acetic acid (IAA) are likely to be crucial during the ripening process, since both hormones have been shown to be implicated in the control of ripening in a range of different fruit species. RESULTS Grapevine (Vitis vinifera L.) homologues of the TRYPTOPHAN AMINOTRANSFERASE RELATED (TAR) and YUCCA families, functioning in the only characterized pathway of auxin biosynthesis, were identified and the expression of several TAR genes was shown to be induced by the pre-ripening application of the ethylene-releasing compound Ethrel. The induction of TAR expression was accompanied by increased IAA and IAA-Asp concentrations, indicative of an upregulation of auxin biosynthesis and conjugation. Exposure of ex planta, pre-ripening berries to the ethylene biosynthesis inhibitor aminoethoxyvinylglycine resulted in decreased IAA and IAA-Asp concentrations. The delayed initiation of ripening observed in Ethrel-treated berries might therefore represent an indirect ethylene effect mediated by increased auxin concentrations. During berry development, the expression of three TAR genes and one YUCCA gene was upregulated at the time of ripening initiation and/or during ripening. This increase in auxin biosynthesis gene expression was preceded by high expression levels of the ethylene biosynthesis genes 1-aminocyclopropane-1-carboxylate synthase and 1-aminocyclopropane-1-carboxylate oxidase. CONCLUSIONS In grape berries, members of both gene families involved in the two-step pathway of auxin biosynthesis are expressed, suggesting that IAA is produced through the combined action of TAR and YUCCA proteins in developing berries. The induction of TAR expression by Ethrel applications and the developmental expression patterns of auxin and ethylene biosynthesis genes indicate that elevated concentrations of ethylene prior to the initiation of ripening might lead to an increased production of IAA, suggesting a complex involvement of this auxin and its conjugates in grape berry ripening.
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Affiliation(s)
| | | | - Paul K Boss
- CSIRO Plant Industry, PO Box 350, Glen Osmond, SA 5064, Australia
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