1
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Baek W, Bae Y, Lim CW, Lee SC. Pepper homeobox abscisic acid signalling-related transcription factor 1, CaHAT1, plays a positive role in drought response. PLANT, CELL & ENVIRONMENT 2023. [PMID: 37128851 DOI: 10.1111/pce.14597] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 03/15/2023] [Accepted: 04/17/2023] [Indexed: 05/03/2023]
Abstract
Abscisic acid (ABA) signalling triggers drought resistance mediated by SNF1-related kinase 2s (SnRK2s), which transmits stress signals through the phosphorylation of several downstream factors. However, these kinases and their downstream targets remain elusive in pepper plants. This study aimed to isolate interacting partners of CaSnRK2.6, a homologue of Arabidopsis SnRK2.6/OST1. Among the candidate proteins, we identified a homeodomain-leucine zipper (HD-Zip) class II protein and named it CaHAT1 (Capsicum annuum homeobox ABA signalling related- transcription factor 1). CaHAT1-silenced pepper and -overexpression (OE) transgenic Arabidopsis plants were generated to investigate the in vivo function of CaHAT1 in drought response. Following the application of drought stress, CaHAT1-silenced pepper plants exhibited drought-sensitive phenotypes with reduced ABA-mediated stomatal closure and lower expression of stress-responsive genes compared with control plants. In contrast, CaHAT1-OE transgenic Arabidopsis plants showed the opposite phenotypes, including increased drought resistance and ABA sensitivity. CaHAT1, particularly its N-terminal consensus sequences, was directly phosphorylated by CaSnRK2.6. Furthermore, CaSnRK2.6 kinase activity and CaSnRK2.6-mediated CaHAT1 phosphorylation levels were enhanced by treatment with ABA and drought stress. Taken together, our results indicated that CaHAT1, which is the target protein of CaSnRK2.6, is a positive regulator of drought stress response. This study advances our understanding of CaHAT1-CaSnRK2.6 mediated defence mechanisms in pepper plants against drought stress.
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Affiliation(s)
- Woonhee Baek
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea
| | - Yeongil Bae
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea
| | - Chae Woo Lim
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea
| | - Sung Chul Lee
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea
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2
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Xu H, Wang S, Larkin RM, Zhang F. The transcription factors DcHB30 and DcWRKY75 antagonistically regulate ethylene-induced petal senescence in carnation (Dianthus caryophyllus). JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:7326-7343. [PMID: 36107792 DOI: 10.1093/jxb/erac357] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023]
Abstract
Although numerous transcription factors with antagonistic activities have been shown to contribute to growth and development, whether and how they regulate senescence in plants is largely unknown. In this study, we investigated the role of antagonistic transcription factors in petal senescence in carnation (Dianthus caryophyllus), one of the most common types of ethylene-sensitive cut flowers produced worldwide. We identified DcHB30 that encodes a ZF-HD transcription factor that is down-regulated in ethylene-treated petal transcriptomes. We found that silencing DcHB30 accelerated ethylene-induced petal senescence and that DcHB30 physically interacts with DcWRKY75, a positive regulator of ethylene-induced petal senescence. Phenotypic characterization and molecular evidence indicated that DcHB30 and DcWRKY75 competitively regulate the expression of their co-targeted genes DcACS1, DcACO1, DcSAG12, and DcSAG29 by reciprocally inhibiting the DNA-binding activity of each other on the gene promoters. This transcriptional regulation mechanism demonstrates that these transcription factors serve as positive and negative regulators in ethylene-induced petal senescence in carnation. Thus, our study provides insights into how antagonizing transcription factors regulate plant senescence.
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Affiliation(s)
- Han Xu
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
- National R&D Center for Citrus Preservation, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Siqi Wang
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
- National R&D Center for Citrus Preservation, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Robert M Larkin
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Fan Zhang
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
- National R&D Center for Citrus Preservation, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
- Key Laboratory of Huazhong Urban Agriculture, Ministry of Agriculture and Rural Affairs, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
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3
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Hasegawa R, Arakawa T, Fujita K, Tanaka Y, Ookawa Z, Sakamoto S, Takasaki H, Ikeda M, Yamagami A, Mitsuda N, Nakano T, Ohme-Takagi M. Arabidopsis homeobox-leucine zipper transcription factor BRASSINOSTEROID-RELATED HOMEOBOX 3 regulates leaf greenness by suppressing BR signaling. PLANT BIOTECHNOLOGY (TOKYO, JAPAN) 2022; 39:209-214. [PMID: 35937537 PMCID: PMC9300418 DOI: 10.5511/plantbiotechnology.22.0128a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 01/28/2022] [Indexed: 06/01/2023]
Abstract
Brassinosteroid (BR) is a phytohormone that acts as important regulator of plant growth. To identify novel transcription factors that may be involved in unknown mechanisms of BR signaling, we screened the chimeric repressor expressing plants (CRES-T), in which transcription factors were converted into chimeric repressors by the fusion of SRDX plant-specific repression domain, to identify those that affect the expression of BR inducible genes. Here, we identified a homeobox-leucine zipper type transcription factor, BRASSINOSTEROID-RELATED-HOMEOBOX 3 (BHB3), of which a chimeric repressor expressing plants (BHB3-sx) significantly downregulated the expression of BAS1 and SAUR-AC1 that are BR inducible genes. Interestingly, ectopic expression of BHB3 (BHB3-ox) also repressed the BR inducible genes and shorten hypocotyl that would be similar to a BR-deficient phenotype. Interestingly, both BHB3-sx and BHB3-ox showed pale green phenotype, in which the expression of genes related photosynthesis and chlorophyll contents were significantly decreased. We found that BHB3 contains three motifs similar to the conserved EAR-repression domain, suggesting that BHB3 may act as a transcriptional repressor. These results indicate that BHB3 might play an important role not only to the BR signaling but also the regulation of greenings.
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Affiliation(s)
- Reika Hasegawa
- Graduate School of Science and Engineering, Saitama University, Saitama, Saitama 338-8570, Japan
| | - Tomoki Arakawa
- Graduate School of Science and Engineering, Saitama University, Saitama, Saitama 338-8570, Japan
| | - Kenjiro Fujita
- RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
| | - Yuichiro Tanaka
- RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
| | - Zen Ookawa
- Plant Gene Regulation Research Group, Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8566, Japan
| | - Shingo Sakamoto
- Plant Gene Regulation Research Group, Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8566, Japan
| | - Hironori Takasaki
- Graduate School of Science and Engineering, Saitama University, Saitama, Saitama 338-8570, Japan
| | - Miho Ikeda
- Graduate School of Science and Engineering, Saitama University, Saitama, Saitama 338-8570, Japan
| | - Ayumi Yamagami
- Graduate School of Biostudies, Kyoto University, Kyoto, Kyoto 606-8502, Japan
| | - Nobutaka Mitsuda
- Plant Gene Regulation Research Group, Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8566, Japan
| | - Takeshi Nakano
- Graduate School of Biostudies, Kyoto University, Kyoto, Kyoto 606-8502, Japan
| | - Masaru Ohme-Takagi
- Graduate School of Science and Engineering, Saitama University, Saitama, Saitama 338-8570, Japan
- Institute of Tropical Plant Science and Microbiology, National Cheng Kung University, Tainan City 701, Taiwan
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4
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Seok HY, Tran HT, Lee SY, Moon YH. AtERF71/ HRE2, an Arabidopsis AP2/ERF Transcription Factor Gene, Contains Both Positive and Negative Cis-Regulatory Elements in Its Promoter Region Involved in Hypoxia and Salt Stress Responses. Int J Mol Sci 2022; 23:ijms23105310. [PMID: 35628120 PMCID: PMC9140466 DOI: 10.3390/ijms23105310] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/03/2022] [Accepted: 05/09/2022] [Indexed: 02/01/2023] Open
Abstract
In the signal transduction network, from the perception of stress signals to stress-responsive gene expression, various transcription factors and cis-regulatory elements in stress-responsive promoters coordinate plant adaptation to abiotic stresses. Among the AP2/ERF transcription factor family, group VII ERF (ERF-VII) genes, such as RAP2.12, RAP2.2, RAP2.3, AtERF73/HRE1, and AtERF71/HRE2, are known to be involved in the response to hypoxia in Arabidopsis. Notably, HRE2 has been reported to be involved in responses to hypoxia and osmotic stress. In this study, we dissected HRE2 promoter to identify hypoxia- and salt stress-responsive region(s). The analysis of the promoter deletion series of HRE2 using firefly luciferase and GUS as reporter genes indicated that the −116 to −2 region is responsible for both hypoxia and salt stress responses. Using yeast one-hybrid screening, we isolated HAT22/ABIG1, a member of the HD-Zip II subfamily, which binds to the −116 to −2 region of HRE2 promoter. Interestingly, HAT22/ABIG1 repressed the transcription of HRE2 via the EAR motif located in the N-terminal region of HAT22/ABIG1. HAT22/ABIG1 bound to the 5′-AATGATA-3′ sequence, HD-Zip II-binding-like cis-regulatory element, in the −116 to −2 region of HRE2 promoter. Our findings demonstrate that the −116 to −2 region of HRE2 promoter contains both positive and negative cis-regulatory elements, which may regulate the expression of HRE2 in responses to hypoxia and salt stress and that HAT22/ABIG1 negatively regulates HRE2 transcription by binding to the HD-Zip II-binding-like element in the promoter region.
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Affiliation(s)
- Hye-Yeon Seok
- Korea Nanobiotechnology Center, Pusan National University, Busan 46241, Korea; (H.-Y.S.); (S.-Y.L.)
| | - Huong Thi Tran
- Department of Integrated Biological Science, Pusan National University, Busan 46241, Korea;
| | - Sun-Young Lee
- Korea Nanobiotechnology Center, Pusan National University, Busan 46241, Korea; (H.-Y.S.); (S.-Y.L.)
| | - Yong-Hwan Moon
- Department of Integrated Biological Science, Pusan National University, Busan 46241, Korea;
- Department of Molecular Biology, Pusan National University, Busan 46241, Korea
- Institute of Systems Biology, Pusan National University, Busan 46241, Korea
- Correspondence: ; Tel.: +82-51-510-2592
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5
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Wu ML, Cui YC, Ge L, Cui LP, Xu ZC, Zhang HY, Wang ZJ, Zhou D, Wu S, Chen L, Cui H. NbCycB2 represses Nbwo activity via a negative feedback loop in tobacco trichome development. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:1815-1827. [PMID: 31990970 PMCID: PMC7242068 DOI: 10.1093/jxb/erz542] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 01/25/2020] [Indexed: 05/20/2023]
Abstract
The transcription factor Woolly (Wo) and its downstream gene CycB2 have been shown to regulate trichome development in tomato (Solanum lycopersicum). It has been demonstrated that only the gain-of-function allele of Slwo (SlWoV, the Slwo woolly motif mutant allele) can increase the trichome density; however, it remains unclear why the two alleles function differently in trichome development. In this study, we used Nicotiana benthamiana as a model and cloned the homologues of Slwo and SlCycB2 (named Nbwo and NbCycB2). We also constructed a Nbwo gain-of-function allele with the same mutation site as SlWoV (named NbWoV). We found that both Nbwo and NbWoV directly regulate NbCycB2 and their own expression by binding to the promoter of NbCycB2 and their own genomic sequences. As form of a feedback regulation, NbCycB2 negatively regulates trichome formation by repressing Nbwo activity at the protein level. We also found that mutations in the Nbwo woolly motif can prevent repression of NbWoV by NbCycB2, which results in a significant increase in the amount of active Nbwo proteins and in increases in trichome density and the number of branches. Our results reveal a novel reciprocal regulation mechanism between NbCycB2 and Nbwo during trichome formation in N. benthamiana.
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Affiliation(s)
- Min-Liang Wu
- Xiamen Key Laboratory for Plant Genetics, School of Life Sciences, Xiamen University, Xiamen, China
- FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yu-Chao Cui
- Xiamen Key Laboratory for Plant Genetics, School of Life Sciences, Xiamen University, Xiamen, China
| | - Li Ge
- Xiamen Key Laboratory for Plant Genetics, School of Life Sciences, Xiamen University, Xiamen, China
| | - Li-Peng Cui
- Xiamen Key Laboratory for Plant Genetics, School of Life Sciences, Xiamen University, Xiamen, China
| | - Zhi-Chao Xu
- Xiamen Key Laboratory for Plant Genetics, School of Life Sciences, Xiamen University, Xiamen, China
| | - Hong-Ying Zhang
- Key Laboratory for Cultivation of Tobacco Industry, College of Tobacco Science, Henan Agricultural University, Zhengzhou, China
| | - Zhao-Jun Wang
- Key Laboratory for Cultivation of Tobacco Industry, College of Tobacco Science, Henan Agricultural University, Zhengzhou, China
| | - Dan Zhou
- Xiamen Key Laboratory for Plant Genetics, School of Life Sciences, Xiamen University, Xiamen, China
| | - Shuang Wu
- FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Liang Chen
- Xiamen Key Laboratory for Plant Genetics, School of Life Sciences, Xiamen University, Xiamen, China
| | - Hong Cui
- Key Laboratory for Cultivation of Tobacco Industry, College of Tobacco Science, Henan Agricultural University, Zhengzhou, China
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6
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Xu M, Zhang MX, Shi YN, Liu XF, Li X, Grierson D, Chen KS. EjHAT1 Participates in Heat Alleviation of Loquat Fruit Lignification by Suppressing the Promoter Activity of Key Lignin Monomer Synthesis Gene EjCAD5. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:5204-5211. [PMID: 30998337 DOI: 10.1021/acs.jafc.9b00641] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Texture attributes such as firmness and lignification are important for fruit quality. Lignification has been widely studied in model plants and energy crops, but fruit lignification has rarely been investigated, despite having an adverse effect on fruit quality and consumer preference. Chilling-induced loquat fruit lignification that occurs after harvest can be alleviated by heat treatment (HT) applied prior to low temperature storage. Enzyme activity assay showed that HT treatment could retard the low temperature-induced increase in cinnamyl alcohol dehydrogenase (CAD) activity. Transcript analysis and substrate activity assays of recombinant CAD proteins highlighted the key role of EjCAD5 in chilling-induced lignin biosynthesis. A novel homeobox-leucine zipper protein ( EjHAT1) was identified as a negative regulator of EjCAD5. Therefore, the effect of HT treatment on lignification may be partially due to the suppression of the EjCAD5 promoter activity by EjHAT1.
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Affiliation(s)
| | | | | | | | | | - Donald Grierson
- Plant and Crop Sciences Division, School of Biosciences , University of Nottingham , Sutton Bonington Campus , Loughborough , LE12 5RD , United Kingdom
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7
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Sessa G, Carabelli M, Possenti M, Morelli G, Ruberti I. Multiple Links between HD-Zip Proteins and Hormone Networks. Int J Mol Sci 2018; 19:ijms19124047. [PMID: 30558150 PMCID: PMC6320839 DOI: 10.3390/ijms19124047] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/06/2018] [Accepted: 12/12/2018] [Indexed: 01/01/2023] Open
Abstract
HD-Zip proteins are unique to plants, and contain a homeodomain closely linked to a leucine zipper motif, which are involved in dimerization and DNA binding. Based on homology in the HD-Zip domain, gene structure and the presence of additional motifs, HD-Zips are divided into four families, HD-Zip I–IV. Phylogenetic analysis of HD-Zip genes using transcriptomic and genomic datasets from a wide range of plant species indicate that the HD-Zip protein class was already present in green algae. Later, HD-Zips experienced multiple duplication events that promoted neo- and sub-functionalizations. HD-Zip proteins are known to control key developmental and environmental responses, and a growing body of evidence indicates a strict link between members of the HD-Zip II and III families and the auxin machineries. Interactions of HD-Zip proteins with other hormones such as brassinolide and cytokinin have also been described. More recent data indicate that members of different HD-Zip families are directly involved in the regulation of abscisic acid (ABA) homeostasis and signaling. Considering the fundamental role of specific HD-Zip proteins in the control of key developmental pathways and in the cross-talk between auxin and cytokinin, a relevant role of these factors in adjusting plant growth and development to changing environment is emerging.
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Affiliation(s)
- Giovanna Sessa
- Institute of Molecular Biology and Pathology, National Research Council, P.le A. Moro 5, 00185 Rome, Italy.
| | - Monica Carabelli
- Institute of Molecular Biology and Pathology, National Research Council, P.le A. Moro 5, 00185 Rome, Italy.
| | - Marco Possenti
- Research Centre for Genomics and Bioinformatics, Council for Agricultural Research and Economics (CREA), Via Ardeatina 546, 00178 Rome, Italy.
| | - Giorgio Morelli
- Research Centre for Genomics and Bioinformatics, Council for Agricultural Research and Economics (CREA), Via Ardeatina 546, 00178 Rome, Italy.
| | - Ida Ruberti
- Institute of Molecular Biology and Pathology, National Research Council, P.le A. Moro 5, 00185 Rome, Italy.
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8
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Sessa G, Carabelli M, Possenti M, Morelli G, Ruberti I. Multiple Pathways in the Control of the Shade Avoidance Response. PLANTS 2018; 7:plants7040102. [PMID: 30453622 PMCID: PMC6313891 DOI: 10.3390/plants7040102] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 11/13/2018] [Accepted: 11/14/2018] [Indexed: 01/09/2023]
Abstract
To detect the presence of neighboring vegetation, shade-avoiding plants have evolved the ability to perceive and integrate multiple signals. Among them, changes in light quality and quantity are central to elicit and regulate the shade avoidance response. Here, we describe recent progresses in the comprehension of the signaling mechanisms underlying the shade avoidance response, focusing on Arabidopsis, because most of our knowledge derives from studies conducted on this model plant. Shade avoidance is an adaptive response that results in phenotypes with a high relative fitness in individual plants growing within dense vegetation. However, it affects the growth, development, and yield of crops, and the design of new strategies aimed at attenuating shade avoidance at defined developmental stages and/or in specific organs in high-density crop plantings is a major challenge for the future. For this reason, in this review, we also report on recent advances in the molecular description of the shade avoidance response in crops, such as maize and tomato, and discuss their similarities and differences with Arabidopsis.
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Affiliation(s)
- Giovanna Sessa
- Institute of Molecular Biology and Pathology, National Research Council, 00185 Rome, Italy.
| | - Monica Carabelli
- Institute of Molecular Biology and Pathology, National Research Council, 00185 Rome, Italy.
| | - Marco Possenti
- Research Centre for Genomics and Bioinformatics, Council for Agricultural Research and Economics (CREA), 00178 Rome, Italy.
| | - Giorgio Morelli
- Research Centre for Genomics and Bioinformatics, Council for Agricultural Research and Economics (CREA), 00178 Rome, Italy.
| | - Ida Ruberti
- Institute of Molecular Biology and Pathology, National Research Council, 00185 Rome, Italy.
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9
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Bedi S, Nag Chaudhuri R. Transcription factor
ABI
3 auto‐activates its own expression during dehydration stress response. FEBS Lett 2018; 592:2594-2611. [DOI: 10.1002/1873-3468.13194] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 06/28/2018] [Accepted: 07/06/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Sonia Bedi
- Department of Biotechnology St. Xavier's College Kolkata India
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10
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Shao J, Haider I, Xiong L, Zhu X, Hussain RMF, Övernäs E, Meijer AH, Zhang G, Wang M, Bouwmeester HJ, Ouwerkerk PBF. Functional analysis of the HD-Zip transcription factor genes Oshox12 and Oshox14 in rice. PLoS One 2018; 13:e0199248. [PMID: 30028850 PMCID: PMC6054374 DOI: 10.1371/journal.pone.0199248] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 06/04/2018] [Indexed: 12/19/2022] Open
Abstract
The homeodomain-leucine zipper (HD-Zip) transcription factor family plays vital roles in plant development and morphogenesis as well as responses to biotic and abiotic stresses. In barley, a recessive mutation in Vrs1 (HvHox1) changes two-rowed barley to six-rowed barley, which improves yield considerably. The Vrs1 gene encodes an HD-Zip subfamily I transcription factor. Phylogenetic analysis has shown that the rice HD-Zip I genes Oshox12 and Oshox14 are the closest homologues of Vrs1. Here, we show that Oshox12 and Oshox14 are ubiquitously expressed with higher levels in developing panicles. Trans-activation assays in yeast and rice protoplasts demonstrated that Oshox12 and Oshox14 can bind to a specific DNA sequence, AH1 (CAAT(A/T)ATTG), and activate reporter gene expression. Overexpression of Oshox12 and Oshox14 in rice resulted in reduced panicle length and a dwarf phenotype. In addition, Oshox14 overexpression lines showed a deficiency in panicle exsertion. Our findings suggest that Oshox12 and Oshox14 may be involved in the regulation of panicle development. This study provides a significant advancement in understanding the functions of HD-Zip transcription factors in rice.
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Affiliation(s)
- Jingxia Shao
- College of Life Sciences, Northwest A&F University, Shaanxi, People’s Republic of China
- Institute of Biology (IBL), Leiden University, Leiden, The Netherlands
| | - Imran Haider
- Institute of Biology (IBL), Leiden University, Leiden, The Netherlands
- Laboratory of Plant Physiology, Wageningen University and Research Centre, Wageningen, The Netherlands
| | - Lizhong Xiong
- National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, People’s Republic of China
| | - Xiaoyi Zhu
- Key Laboratory of Biology and Genetic Improvement of Oil Crops of Ministry of Agriculture, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, People’s Republic of China
| | | | - Elin Övernäs
- Department of Physiological Botany, EBC, Uppsala University, Uppsala, Sweden
| | | | - Gaisheng Zhang
- College of Agronomy, Northwest A&F University, Shaanxi, People’s Republic of China
| | - Mei Wang
- Institute of Biology (IBL), Leiden University, Leiden, The Netherlands
- Leiden University European Center for Chinese Medicine and Natural Compounds, Leiden, The Netherlands
| | - Harro J. Bouwmeester
- Laboratory of Plant Physiology, Wageningen University and Research Centre, Wageningen, The Netherlands
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11
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Tan W, Zhang D, Zhou H, Zheng T, Yin Y, Lin H. Transcription factor HAT1 is a substrate of SnRK2.3 kinase and negatively regulates ABA synthesis and signaling in Arabidopsis responding to drought. PLoS Genet 2018; 14:e1007336. [PMID: 29659577 PMCID: PMC5919683 DOI: 10.1371/journal.pgen.1007336] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 04/26/2018] [Accepted: 03/27/2018] [Indexed: 11/19/2022] Open
Abstract
Drought is a major threat to plant growth and crop productivity. The phytohormone abscisic acid (ABA) plays a critical role in plant response to drought stress. Although ABA signaling-mediated drought tolerance has been widely investigated in Arabidopsis thaliana, the feedback mechanism and components negatively regulating this pathway are less well understood. Here we identified a member of Arabidopsis HD-ZIP transcription factors HAT1 which can interacts with and be phosphorylated by SnRK2s. hat1hat3, loss-of-function mutant of HAT1 and its homolog HAT3, was hypersensitive to ABA in primary root inhibition, ABA-responsive genes expression, and displayed enhanced drought tolerance, whereas HAT1 overexpressing lines were hyposensitive to ABA and less tolerant to drought stress, suggesting that HAT1 functions as a negative regulator in ABA signaling-mediated drought response. Furthermore, expression levels of ABA biosynthesis genes ABA3 and NCED3 were repressed by HAT1 directly binding to their promoters, resulting in the ABA level was increased in hat1hat3 and reduced in HAT1OX lines. Further evidence showed that both protein stability and binding activity of HAT1 was repressed by SnRK2.3 phosphorylation. Overexpressing SnRK2.3 in HAT1OX transgenic plant made a reduced HAT1 protein level and suppressed the HAT1OX phenotypes in ABA and drought response. Our results thus establish a new negative regulation mechanism of HAT1 which helps plants fine-tune their drought responses.
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Affiliation(s)
- Wenrong Tan
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan, P.R. China
| | - Dawei Zhang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan, P.R. China
- * E-mail: (DZ); (HL)
| | - Huapeng Zhou
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan, P.R. China
| | - Ting Zheng
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan, P.R. China
| | - Yanhai Yin
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, United States of America
| | - Honghui Lin
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan, P.R. China
- * E-mail: (DZ); (HL)
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12
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Gallemí M, Molina-Contreras MJ, Paulišić S, Salla-Martret M, Sorin C, Godoy M, Franco-Zorrilla JM, Solano R, Martínez-García JF. A non-DNA-binding activity for the ATHB4 transcription factor in the control of vegetation proximity. THE NEW PHYTOLOGIST 2017; 216:798-813. [PMID: 28805249 DOI: 10.1111/nph.14727] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 06/29/2017] [Indexed: 05/20/2023]
Abstract
In plants, perception of vegetation proximity by phytochrome photoreceptors activates a transcriptional network that implements a set of responses to adapt to plant competition, including elongation of stems or hypocotyls. In Arabidopsis thaliana, the homeodomain-leucine zipper (HD-Zip) transcription factor ARABIDOPSIS THALIANA HOMEOBOX 4 (ATHB4) regulates this and other responses, such as leaf polarity. To better understand the shade regulatory transcriptional network, we have carried out structure-function analyses of ATHB4 by overexpressing a series of truncated and mutated forms and analyzing three different responses: hypocotyl response to shade, transcriptional activity and leaf polarity. Our results indicated that ATHB4 has two physically separated molecular activities: that performed by HD-Zip, which is involved in binding to DNA-regulatory elements, and that performed by the ETHYLENE-RESPONSIVE ELEMENT BINDING FACTOR-associated amphiphilic repression (EAR)-containing N-terminal region, which is involved in protein-protein interaction. Whereas both activities are required to regulate leaf polarity, DNA-binding activity is not required for the regulation of the seedling responses to plant proximity, which indicates that ATHB4 works as a transcriptional cofactor in the regulation of this response. These findings suggest that transcription factors might employ alternative mechanisms of action to regulate different developmental processes.
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Affiliation(s)
- Marçal Gallemí
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, 08193, Spain
| | - Maria Jose Molina-Contreras
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, 08193, Spain
| | - Sandi Paulišić
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, 08193, Spain
| | - Mercè Salla-Martret
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, 08193, Spain
| | - Céline Sorin
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, 08193, Spain
| | - Marta Godoy
- National Centre for Biotechnology (CNB), CSIC, Campus University Autónoma, Madrid, 28049, Spain
| | | | - Roberto Solano
- National Centre for Biotechnology (CNB), CSIC, Campus University Autónoma, Madrid, 28049, Spain
| | - Jaime F Martínez-García
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, 08193, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, 08010, Spain
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13
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Roodbarkelari F, Groot EP. Regulatory function of homeodomain-leucine zipper (HD-ZIP) family proteins during embryogenesis. THE NEW PHYTOLOGIST 2017; 213:95-104. [PMID: 27523393 DOI: 10.1111/nph.14132] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 07/04/2016] [Indexed: 05/26/2023]
Abstract
Homeodomain-leucine zipper proteins (HD-ZIPs) form a plant-specific family of transcription factors functioning as homo- or heterodimers. Certain members of all four classes of this family are involved in embryogenesis, the focus of this review. They support auxin biosynthesis, transport and response, which are in turn essential for the apical-basal patterning of the embryo, radicle formation and outgrowth of the cotyledons. They transcriptionally regulate meristem regulators to maintain the shoot apical meristem once it is initiated. Some members are specific to the protoderm, the outermost layer of the embryo, and play a role in shoot apical meristem function. Within classes, homeodomain-leucine zippers tend to act redundantly during embryo development, and there are many examples of regulation within and between classes of homeodomain-leucine zippers. This indicates a complex network of regulation that awaits future experiments to uncover.
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Affiliation(s)
| | - Edwin P Groot
- Institute of Biology III, Albert-Ludwigs-Universität, Freiburg 79104, Germany
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14
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Wei J, Choi H, Jin P, Wu Y, Yoon J, Lee YS, Quan T, An G. GL2-type homeobox gene Roc4 in rice promotes flowering time preferentially under long days by repressing Ghd7. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2016; 252:133-143. [PMID: 27717449 DOI: 10.1016/j.plantsci.2016.07.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 07/18/2016] [Accepted: 07/19/2016] [Indexed: 06/06/2023]
Abstract
Under long day (LD) lengths, flowering can be delayed in rice by modulating several regulatory genes. We found activation tagging lines that showed an early flowering phenotype preferentially under LD conditions. Expression of Rice outermost cell-specific gene 4 (Roc4), encoding a homeodomain Leu-zipper class IV family protein, was significantly increased. Transcript levels of Grain number, plant height, and heading date7 (Ghd7) were significantly reduced while those of Ghd7 downstream genes were increased. However, other flowering regulators were unaffected. Whereas constitutive overexpression of Roc4 in 'Dongjin' japonica rice, which carries active Ghd7, also caused LD-preferential early flowering, its overexpression in 'Longjing27' rice, which is defective in functional Ghd7, did not produce the same result. This confirmed that Roc4 regulates flowering time mainly through Ghd7. Phytochromes and O. sativa GIGANTEA (OsGI) function upstream of Roc4. Transgenic plants showed ubiquitous expression of the β-glucuronidase reporter gene under the Roc4 promoter. Furthermore, Roc4 had transcriptional activation activity in the N-terminal region of the StAR-related lipid-transfer domain. All of these findings are evidence that Roc4 is an LD-preferential flowering enhancer that functions downstream of phytochromes and OsGI, but upstream of Ghd7.
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Affiliation(s)
- Jinhuan Wei
- Crop Biotech Institute, Kyung Hee University, Yongin 446-701, Republic of Korea
| | - Heebak Choi
- Crop Biotech Institute, Kyung Hee University, Yongin 446-701, Republic of Korea; Department of Life Science, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Ping Jin
- Crop Biotech Institute, Kyung Hee University, Yongin 446-701, Republic of Korea
| | - Yunfei Wu
- Crop Biotech Institute, Kyung Hee University, Yongin 446-701, Republic of Korea
| | - Jinmi Yoon
- Crop Biotech Institute, Kyung Hee University, Yongin 446-701, Republic of Korea
| | - Yang-Seok Lee
- Crop Biotech Institute, Kyung Hee University, Yongin 446-701, Republic of Korea
| | - Taiyong Quan
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, College of Life Science, Shandong University, Jinan 250100, People's Republic of China
| | - Gynheung An
- Crop Biotech Institute, Kyung Hee University, Yongin 446-701, Republic of Korea.
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15
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Liu T, Longhurst AD, Talavera-Rauh F, Hokin SA, Barton MK. The Arabidopsis transcription factor ABIG1 relays ABA signaled growth inhibition and drought induced senescence. eLife 2016; 5:e13768. [PMID: 27697148 PMCID: PMC5050019 DOI: 10.7554/elife.13768] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Accepted: 08/31/2016] [Indexed: 01/04/2023] Open
Abstract
Drought inhibits plant growth and can also induce premature senescence. Here we identify a transcription factor, ABA INSENSITIVE GROWTH 1 (ABIG1) required for abscisic acid (ABA) mediated growth inhibition, but not for stomatal closure. ABIG1 mRNA levels are increased both in response to drought and in response to ABA treatment. When treated with ABA, abig1 mutants remain greener and produce more leaves than comparable wild-type plants. When challenged with drought, abig1 mutants have fewer yellow, senesced leaves than wild-type. Induction of ABIG1 transcription mimics ABA treatment and regulates a set of genes implicated in stress responses. We propose a model in which drought acts through ABA to increase ABIG1 transcription which in turn restricts new shoot growth and promotes leaf senescence. The results have implications for plant breeding: the existence of a mutant that is both ABA resistant and drought resistant points to new strategies for isolating drought resistant genetic varieties.
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Affiliation(s)
- Tie Liu
- Department of Plant Biology, Carnegie Institution for Science, Stanford, United States
| | - Adam D Longhurst
- Department of Plant Biology, Carnegie Institution for Science, Stanford, United States
| | | | - Samuel A Hokin
- Department of Plant Biology, Carnegie Institution for Science, Stanford, United States
| | - M Kathryn Barton
- Department of Plant Biology, Carnegie Institution for Science, Stanford, United States
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16
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Zou LJ, Deng XG, Han XY, Tan WR, Zhu LJ, Xi DH, Zhang DW, Lin HH. Role of Transcription Factor HAT1 in Modulating Arabidopsis thaliana Response to Cucumber mosaic virus. PLANT & CELL PHYSIOLOGY 2016; 57:1879-1889. [PMID: 27328697 DOI: 10.1093/pcp/pcw109] [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: 03/22/2016] [Accepted: 05/31/2016] [Indexed: 06/06/2023]
Abstract
Arabidopsis thaliana homeodomain-leucine zipper protein 1 (HAT1) belongs to the homeodomain-leucine zipper (HD-Zip) family class II that plays important roles in plant growth and development as a transcription factor. To elucidate further the role of HD-Zip II transcription factors in plant defense, the A. thaliana hat1, hat1hat3 and hat1hat2hat3 mutants and HAT1 overexpression plants (HAT1OX) were challenged with Cucumber mosaic virus (CMV). HAT1OX displayed more susceptibility, while loss-of-function mutants of HAT1 exhibited less susceptibility to CMV infection. HAT1 and its close homologs HAT2 and HAT3 function redundantly, as the triple mutant hat1hat2hat3 displayed increased virus resistance compared with the hat1 and hat1hat3 mutants. Furthermore, the induction of the antioxidant system (the activities and expression of enzymatic antioxidants) and the expression of defense-associated genes were down-regulated in HAT1OX but up-regulated in hat1hat2hat3 when compared with Col-0 after CMV infection. Further evidence showed that the involvement of HAT1 in the anti-CMV defense response might be dependent on salicylic acid (SA) but not jasmonic acid (JA). The SA level or expression of SA synthesis-related genes was decreased in HAT1OX but increased in hat1hat2hat3 compared with Col-0 after CMV infection, but there were little difference in JA level or JA synthesis-related gene expression among HAT1OX or defective plants. In addition, HAT1 expression is dependent on SA accumulation. Taken together, our study indicated that HAT1 negatively regulates plant defense responses to CMV.
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Affiliation(s)
- Li-Juan Zou
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China Life Science and Technology College and Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianyang 621000, China These authors contributed equally to this work
| | - Xing-Guang Deng
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China These authors contributed equally to this work
| | - Xue-Ying Han
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China
| | - Wen-Rong Tan
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China
| | - Li-Jun Zhu
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China Life Science and Technology College and Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianyang 621000, China
| | - De-Hui Xi
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China
| | - Da-Wei Zhang
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China These authors contributed equally to this work.
| | - Hong-Hui Lin
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China
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17
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Min L, Hu Q, Li Y, Xu J, Ma Y, Zhu L, Yang X, Zhang X. LEAFY COTYLEDON1-CASEIN KINASE I-TCP15-PHYTOCHROME INTERACTING FACTOR4 Network Regulates Somatic Embryogenesis by Regulating Auxin Homeostasis. PLANT PHYSIOLOGY 2015; 169:2805-21. [PMID: 26491146 PMCID: PMC4677921 DOI: 10.1104/pp.15.01480] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 10/21/2015] [Indexed: 05/19/2023]
Abstract
Somatic embryogenesis (SE) is an efficient tool for the propagation of plant species and also, a useful model for studying the regulatory networks in embryo development. However, the regulatory networks underlying the transition from nonembryogenic callus to somatic embryos during SE remain poorly understood. Here, we describe an upland cotton (Gossypium hirsutum) CASEIN KINASE I gene, GhCKI, which is a unique key regulatory factor that strongly affects SE. Overexpressing GhCKI halted the formation of embryoids and plant regeneration because of a block in the transition from nonembryogenic callus to somatic embryos. In contrast, defective GhCKI in plants facilitated SE. To better understand the mechanism by which GhCKI regulates SE, the regulatory network was analyzed. A direct upstream negative regulator protein, cotton LEAFY COTYLEDON1, was identified to be targeted to a cis-element, CTTTTC, in the promoter of GhCKI. Moreover, GhCKI interacted with and phosphorylated cotton CINCINNATA-like TEOSINTE BRANCHED1-CYCLOIDEA-PCF transcription factor15 by coordinately regulating the expression of cotton PHYTOCHROME INTERACTING FACTOR4, finally disrupting auxin homeostasis, which led to increased cell proliferation and aborted somatic embryo formation in GhCKI-overexpressing somatic cells. Our results show a complex process of SE that is negatively regulated by GhCKI through a complex regulatory network.
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Affiliation(s)
- Ling Min
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Qin Hu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Yaoyao Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Jiao Xu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Yizan Ma
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Longfu Zhu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Xiyan Yang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Xianlong Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
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18
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Turchi L, Baima S, Morelli G, Ruberti I. Interplay of HD-Zip II and III transcription factors in auxin-regulated plant development. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:5043-53. [PMID: 25911742 DOI: 10.1093/jxb/erv174] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The homeodomain-leucine zipper (HD-Zip) class of transcription factors is unique to plants. HD-Zip proteins bind to DNA exclusively as dimers recognizing dyad symmetric sequences and act as positive or negative regulators of gene expression. On the basis of sequence homology in the HD-Zip DNA-binding domain, HD-Zip proteins have been grouped into four families (HD-Zip I-IV). Each HD-Zip family can be further divided into subfamilies containing paralogous genes that have arisen through genome duplication. Remarkably, all the members of the HD-Zip IIγ and -δ clades are regulated by light quality changes that induce in the majority of the angiosperms the shade-avoidance response, a process regulated at multiple levels by auxin. Intriguingly, it has recently emerged that, apart from their function in shade avoidance, the HD-Zip IIγ and -δ transcription factors control several auxin-regulated developmental processes, including apical embryo patterning, lateral organ polarity, and gynoecium development, in a white-light environment. This review presents recent advances in our understanding of HD-Zip II protein function in plant development, with particular emphasis on the impact of loss-of-function HD-Zip II mutations on auxin distribution and response. The review also describes evidence demonstrating that HD-Zip IIγ and -δ genes are directly and positively regulated by HD-Zip III transcription factors, primary determinants of apical shoot development, known to control the expression of several auxin biosynthesis, transport, and response genes. Finally, the interplay between HD-Zip II and III transcription factors in embryo apical patterning and organ polarity is discussed.
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Affiliation(s)
- L Turchi
- Institute of Molecular Biology and Pathology, National Research Council, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - S Baima
- Food and Nutrition Research Centre, Agricultural Research Council, Via Ardeatina 546, 00178 Rome, Italy
| | - G Morelli
- Food and Nutrition Research Centre, Agricultural Research Council, Via Ardeatina 546, 00178 Rome, Italy
| | - I Ruberti
- Institute of Molecular Biology and Pathology, National Research Council, Piazzale Aldo Moro 5, 00185 Rome, Italy
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19
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Brandt R, Cabedo M, Xie Y, Wenkel S. Homeodomain leucine-zipper proteins and their role in synchronizing growth and development with the environment. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2014; 56:518-26. [PMID: 24528801 DOI: 10.1111/jipb.12185] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 01/25/2014] [Indexed: 05/21/2023]
Abstract
The Arabidopsis (Arabidopsis thaliana L.) genome encodes for four distinct classes of homeodomain leucine-zipper (HD-ZIP) transcription factors (HD-ZIPI to HD-ZIPIV), which are all organized in multi-gene families. HD-ZIP transcription factors act as sequence-specific DNA-binding proteins that are able to control the expression level of target genes. While HD-ZIPI and HD-ZIPII proteins are mainly associated with environmental responses, HD-ZIPIII and HD-ZIPIV are primarily known to act as patterning factors. Recent studies have challenged this view. It appears that several of the different HD-ZIP families interact genetically to align both morphogenesis and environmental responses, most likely by modulating phytohormone-signaling networks.
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Affiliation(s)
- Ronny Brandt
- Center for Plant Molecular Biology, University of Tübingen, Germany; Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
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20
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Rice EA, Khandelwal A, Creelman RA, Griffith C, Ahrens JE, Taylor JP, Murphy LR, Manjunath S, Thompson RL, Lingard MJ, Back SL, Larue H, Brayton BR, Burek AJ, Tiwari S, Adam L, Morrell JA, Caldo RA, Huai Q, Kouadio JLK, Kuehn R, Sant AM, Wingbermuehle WJ, Sala R, Foster M, Kinser JD, Mohanty R, Jiang D, Ziegler TE, Huang MG, Kuriakose SV, Skottke K, Repetti PP, Reuber TL, Ruff TG, Petracek ME, Loida PJ. Expression of a truncated ATHB17 protein in maize increases ear weight at silking. PLoS One 2014; 9:e94238. [PMID: 24736658 PMCID: PMC3988052 DOI: 10.1371/journal.pone.0094238] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 03/12/2014] [Indexed: 12/11/2022] Open
Abstract
ATHB17 (AT2G01430) is an Arabidopsis gene encoding a member of the α-subclass of the homeodomain leucine zipper class II (HD-Zip II) family of transcription factors. The ATHB17 monomer contains four domains common to all class II HD-Zip proteins: a putative repression domain adjacent to a homeodomain, leucine zipper, and carboxy terminal domain. However, it also possesses a unique N-terminus not present in other members of the family. In this study we demonstrate that the unique 73 amino acid N-terminus is involved in regulation of cellular localization of ATHB17. The ATHB17 protein is shown to function as a transcriptional repressor and an EAR-like motif is identified within the putative repression domain of ATHB17. Transformation of maize with an ATHB17 expression construct leads to the expression of ATHB17Δ113, a truncated protein lacking the first 113 amino acids which encodes a significant portion of the repression domain. Because ATHB17Δ113 lacks the repression domain, the protein cannot directly affect the transcription of its target genes. ATHB17Δ113 can homodimerize, form heterodimers with maize endogenous HD-Zip II proteins, and bind to target DNA sequences; thus, ATHB17Δ113 may interfere with HD-Zip II mediated transcriptional activity via a dominant negative mechanism. We provide evidence that maize HD-Zip II proteins function as transcriptional repressors and that ATHB17Δ113 relieves this HD-Zip II mediated transcriptional repression activity. Expression of ATHB17Δ113 in maize leads to increased ear size at silking and, therefore, may enhance sink potential. We hypothesize that this phenotype could be a result of modulation of endogenous HD-Zip II pathways in maize.
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Affiliation(s)
- Elena A. Rice
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Abha Khandelwal
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Robert A. Creelman
- Mendel Biotechnology Inc., Hayward, California, United States of America
| | - Cara Griffith
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | | | | | - Siva Manjunath
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | | | | | - Huachun Larue
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Bonnie R. Brayton
- Dupont-Pioneer Hi-Bred International, Waipahu, Hawaii, United States of America
| | - Amanda J. Burek
- Mendel Biotechnology Inc., Hayward, California, United States of America
| | - Shiv Tiwari
- Dupont-Pioneer Hi-Bred International, Hayward, California, United States of America
| | - Luc Adam
- ABCAM, Burlingame, California, United States of America
| | | | - Rico A. Caldo
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Qing Huai
- Monsanto Company, Cambridge, Massachusetts, United States of America
| | | | - Rosemarie Kuehn
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Anagha M. Sant
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | - Rodrigo Sala
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Matt Foster
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Josh D. Kinser
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Radha Mohanty
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Dongming Jiang
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Todd E. Ziegler
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Mingya G. Huang
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | - Kyle Skottke
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Peter P. Repetti
- Mendel Biotechnology Inc., Hayward, California, United States of America
| | - T. Lynne Reuber
- Mendel Biotechnology Inc., Hayward, California, United States of America
| | - Thomas G. Ruff
- Monsanto Company, St. Louis, Missouri, United States of America
| | | | - Paul J. Loida
- Monsanto Company, St. Louis, Missouri, United States of America
- * E-mail:
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21
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Zhang D, Ye H, Guo H, Johnson A, Zhang M, Lin H, Yin Y. Transcription factor HAT1 is phosphorylated by BIN2 kinase and mediates brassinosteroid repressed gene expression in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 77:59-70. [PMID: 24164091 DOI: 10.1111/tpj.12368] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 10/11/2013] [Accepted: 10/16/2013] [Indexed: 05/03/2023]
Abstract
Plant steroid hormones, brassinosteroids (BRs), play essential roles in modulating cell elongation, vascular differentiation, senescence and stress responses. BRs signal through plasma membrane-localized receptor and other components to modulate the BES1/BZR1 (BRI1-EMS SUPPRESSOR 1/BRASSINAZOLE RESISTANT 1) family of transcription factors that modulate thousands of target genes. Arabodopsis thaliana homeodomain-leucine zipper protein 1 (HAT1), which encodes a homeodomain-leucine zipper (HD-Zip) class II transcription factor, was identified through chromatin immunoprecipitation (ChIP) experiments as a direct target gene of BES1. Loss-of-function and gain-of-function mutants of HAT1 display altered BR responses. HAT1 and its close homolog HAT3 act redundantly, as the double mutant hat1 hat3 displayed a reduced BR response that is stronger than the single mutants alone. Moreover, hat1 hat3 enhanced the phenotype of a weak allele of the BR receptor mutant bri1 and suppressed the phenotype of constitutive BR response mutant bes1-D. These results suggest that HAT1 and HAT3 function to activate BR-mediated growth. Expression levels of several BR-repressed genes are increased in hat1 hat3 and reduced in HAT1OX, suggesting that HAT1 functions to repress the expression of a subset of BR target genes. HAT1 and BES1 bind to a conserved homeodomain binding (HB) site and BR response element (BRRE) respectively, in the promoters of some BR-repressed genes. BES1 and HAT1 interact with each other and cooperate to inhibit BR-repressed gene expression. Furthermore, HAT1 can be phosphorylated and stabilized by GSK3 (GLYCOGEN SYNTHASE KINASE 3)-like kinase BIN2 (BRASSINOSTEROID-INSENSITIVE 2), a well established negative regulator of the BR pathway. Our results thus revealed a previously unknown mechanism by which BR signaling modulates BR-repressed gene expression and coordinates plant growth.
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Affiliation(s)
- Dawei Zhang
- College of Life Science, Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China; Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA
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22
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Hymus GJ, Cai S, Kohl EA, Holtan HE, Marion CM, Tiwari S, Maszle DR, Lundgren MR, Hong MC, Channa N, Loida P, Thompson R, Taylor JP, Rice E, Repetti PP, Ratcliffe OJ, Reuber TL, Creelman RA. Application of HB17, an Arabidopsis class II homeodomain-leucine zipper transcription factor, to regulate chloroplast number and photosynthetic capacity. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:4479-90. [PMID: 24006420 PMCID: PMC3808327 DOI: 10.1093/jxb/ert261] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Transcription factors are proposed as suitable targets for the control of traits such as yield or food quality in plants. This study reports the results of a functional genomics research effort that identified ATHB17, a transcription factor from the homeodomain-leucine zipper class II family, as a novel target for the enhancement of photosynthetic capacity. It was shown that ATHB17 is expressed natively in the root quiescent centre (QC) from Arabidopsis embryos and seedlings. Analysis of the functional composition of genes differentially expressed in the QC from a knockout mutant (athb17-1) compared with its wild-type sibling revealed the over-representation of genes involved in auxin stimulus, embryo development, axis polarity specification, and plastid-related processes. While no other phenotypes were observed in athb17-1 plants, overexpression of ATHB17 produced a number of phenotypes in Arabidopsis including enhanced chlorophyll content. Image analysis of isolated mesophyll cells of 35S::ATHB17 lines revealed an increase in the number of chloroplasts per unit cell size, which is probably due to an increase in the number of proplastids per meristematic cell. Leaf physiological measurements provided evidence of improved photosynthetic capacity in 35S::ATHB17 lines on a per unit leaf area basis. Estimates of the capacity for ribulose-1,5-bisphosphate-saturated and -limited photosynthesis were significantly higher in 35S::ATHB17 lines.
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Affiliation(s)
- Graham J. Hymus
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
| | - Suqin Cai
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
| | - Elizabeth A. Kohl
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
- * Present address: Artic Distribution LLC, Lipan, TX 76462, USA
| | - Hans E. Holtan
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
| | | | - Shiv Tiwari
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
- Present address: Dupont-Pioneer Hi-Bred International, Hayward, CA 94546, USA
| | - Don R. Maszle
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
| | - Marjorie R. Lundgren
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
- Present address: Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Melissa C. Hong
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
| | - Namitha Channa
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
- Present address: Snapwiz, Fremont, CA 94568, USA
| | - Paul Loida
- Monsanto Company, 700 Chesterfield Parkway North, Chesterfield, MO 63017, USA
| | - Rebecca Thompson
- Monsanto Company, 700 Chesterfield Parkway North, Chesterfield, MO 63017, USA
| | - J. Philip Taylor
- Monsanto Company, 700 Chesterfield Parkway North, Chesterfield, MO 63017, USA
| | - Elena Rice
- Monsanto Company, 700 Chesterfield Parkway North, Chesterfield, MO 63017, USA
| | - Peter P. Repetti
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
| | | | - T. Lynne Reuber
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
| | - Robert A. Creelman
- Mendel Biotechnology, 3935 Point Eden Way, Hayward, CA 94545, USA
- To whom correspondence should be addressed.
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23
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Carabelli M, Turchi L, Ruzza V, Morelli G, Ruberti I. Homeodomain-Leucine Zipper II family of transcription factors to the limelight: central regulators of plant development. PLANT SIGNALING & BEHAVIOR 2013; 8:25447. [PMID: 23838958 PMCID: PMC4002598 DOI: 10.4161/psb.25447] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 06/18/2013] [Indexed: 05/20/2023]
Abstract
The Arabidopsis genome encodes 10 Homeodomain-Leucine Zipper (HD-Zip) II transcription factors that can be subdivided into 4 clades (α-δ). All the γ (ARABIDOPSIS THALIANA HOMEOBOX 2 [ATHB2], HOMEOBOX ARABIDOPSIS THALIANA 1 [HAT1], HAT2) and δ (HAT3, ATHB4) genes are regulated by light quality changes (Low Red [R]/Far-Red [FR]) that induce the shade avoidance response in most of the angiosperms. HD-Zip IIγ and HD-Zip IIδ transcription factors function as positive regulators of shade avoidance, and there is evidence that at least ATHB2 is directly positively regulated by the basic Helix-Loop-Helix (bHLH) proteins PHYTOCHROME INTERACTING FACTOR 4 (PIF4) and PIF5. Recent evidence demonstrate that, in addition to their function in shade avoidance, HD-Zip IIγ and HD-Zip IIδ proteins play an essential role in plant development from embryogenesis onwards in a white light environment.
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Affiliation(s)
- Monica Carabelli
- Institute of Molecular Biology and Pathology; National Research Council; Rome, Italy
| | - Luana Turchi
- Institute of Molecular Biology and Pathology; National Research Council; Rome, Italy
| | - Valentino Ruzza
- Institute of Molecular Biology and Pathology; National Research Council; Rome, Italy
| | - Giorgio Morelli
- Food and Nutrition Research Centre; Agricultural Research Council (CRA); Rome, Italy
| | - Ida Ruberti
- Institute of Molecular Biology and Pathology; National Research Council; Rome, Italy
- Correspondence to: Ida Ruberti,
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24
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De Smet I, Lau S, Ehrismann JS, Axiotis I, Kolb M, Kientz M, Weijers D, Jürgens G. Transcriptional repression of BODENLOS by HD-ZIP transcription factor HB5 in Arabidopsis thaliana. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:3009-19. [PMID: 23682118 PMCID: PMC3697942 DOI: 10.1093/jxb/ert137] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In Arabidopsis thaliana, the phytohormone auxin is an important patterning agent during embryogenesis and post-embryonic development, exerting effects through transcriptional regulation. The main determinants of the transcriptional auxin response machinery are AUXIN RESPONSE FACTOR (ARF) transcription factors and AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) inhibitors. Although members of these two protein families are major developmental regulators, the transcriptional regulation of the genes encoding them has not been well explored. For example, apart from auxin-linked regulatory inputs, factors regulating the expression of the AUX/IAA BODENLOS (BDL)/IAA12 are not known. Here, it was shown that the HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIP) transcription factor HOMEOBOX PROTEIN 5 (HB5) negatively regulates BDL expression, which may contribute to the spatial control of BDL expression. As such, HB5 and probably other class I HD-ZIP proteins, appear to modulate BDL-dependent auxin response.
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Affiliation(s)
- Ive De Smet
- Department of Cell Biology, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
- Center for Plant Molecular Biology, University of Tübingen, D-72076 Tübingen, Germany
- Present address: Plant and Crop Sciences Division, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, UK.
- * These authors contributed equally to this work
| | - Steffen Lau
- Department of Cell Biology, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
- * These authors contributed equally to this work
| | - Jasmin S. Ehrismann
- Center for Plant Molecular Biology, University of Tübingen, D-72076 Tübingen, Germany
- * These authors contributed equally to this work
| | - Ioannis Axiotis
- Department of Cell Biology, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
| | - Martina Kolb
- Department of Cell Biology, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
| | - Marika Kientz
- Center for Plant Molecular Biology, University of Tübingen, D-72076 Tübingen, Germany
| | - Dolf Weijers
- Center for Plant Molecular Biology, University of Tübingen, D-72076 Tübingen, Germany
- Present address: Laboratory of Biochemistry, Wageningen University, Dreijenlaan 3, 6703 HA Wageningen, The Netherlands
| | - Gerd Jürgens
- Department of Cell Biology, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
- Center for Plant Molecular Biology, University of Tübingen, D-72076 Tübingen, Germany
- To whom correspondence should be addressed.
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25
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Turchi L, Carabelli M, Ruzza V, Possenti M, Sassi M, Peñalosa A, Sessa G, Salvi S, Forte V, Morelli G, Ruberti I. Arabidopsis HD-Zip II transcription factors control apical embryo development and meristem function. Development 2013; 140:2118-29. [PMID: 23578926 DOI: 10.1242/dev.092833] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The Arabidopsis genome encodes ten Homeodomain-Leucine zipper (HD-Zip) II proteins. ARABIDOPSIS THALIANA HOMEOBOX 2 (ATHB2), HOMEOBOX ARABIDOPSIS THALIANA 1 (HAT1), HAT2, HAT3 and ATHB4 are regulated by changes in the red/far red light ratio that induce shade avoidance in most of the angiosperms. Here, we show that progressive loss of HAT3, ATHB4 and ATHB2 activity causes developmental defects from embryogenesis onwards in white light. Cotyledon development and number are altered in hat3 athb4 embryos, and these defects correlate with changes in auxin distribution and response. athb2 gain-of-function mutation and ATHB2 expression driven by its promoter in hat3 athb4 result in significant attenuation of phenotypes, thus demonstrating that ATHB2 is functionally redundant to HAT3 and ATHB4. In analogy to loss-of-function mutations in HD-Zip III genes, loss of HAT3 and ATHB4 results in organ polarity defects, whereas triple hat3 athb4 athb2 mutants develop one or two radialized cotyledons and lack an active shoot apical meristem (SAM). Consistent with overlapping expression pattern of HD-Zip II and HD-Zip III gene family members, bilateral symmetry and SAM defects are enhanced when hat3 athb4 is combined with mutations in PHABULOSA (PHB), PHAVOLUTA (PHV) or REVOLUTA (REV). Finally, we show that ATHB2 is part of a complex regulatory circuit directly involving both HD-Zip II and HD-Zip III proteins. Taken together, our study provides evidence that a genetic system consisting of HD-Zip II and HD-Zip III genes cooperates in establishing bilateral symmetry and patterning along the adaxial-abaxial axis in the embryo as well as in controlling SAM activity.
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Affiliation(s)
- Luana Turchi
- Institute of Molecular Biology and Pathology, National Research Council, P.le A. Moro 5, 00185 Rome, Italy
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26
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Zhang S, Haider I, Kohlen W, Jiang L, Bouwmeester H, Meijer AH, Schluepmann H, Liu CM, Ouwerkerk PBF. Function of the HD-Zip I gene Oshox22 in ABA-mediated drought and salt tolerances in rice. PLANT MOLECULAR BIOLOGY 2012; 80:571-85. [PMID: 23109182 DOI: 10.1007/s11103-012-9967-1] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 09/04/2012] [Indexed: 05/02/2023]
Abstract
Oshox22 belongs to the homeodomain-leucine zipper (HD-Zip) family I of transcription factors, most of which have unknown functions. Here we show that the expression of Oshox22 is strongly induced by salt stress, abscisic acid (ABA), and polyethylene glycol treatment (PEG), and weakly by cold stress. Trans-activation assays in yeast and transient expression analyses in rice protoplasts demonstrated that Oshox22 is able to bind the CAAT(G/C)ATTG element and acts as a transcriptional activator that requires both the HD and Zip domains. Rice plants homozygous for a T-DNA insertion in the promoter region of Oshox22 showed reduced Oshox22 expression and ABA content, decreased sensitivity to ABA, and enhanced tolerance to drought and salt stresses at the seedling stage. In contrast, transgenic rice over-expressing Oshox22 showed increased sensitivity to ABA, increased ABA content, and decreased drought and salt tolerances. Based on these results, we conclude that Oshox22 affects ABA biosynthesis and regulates drought and salt responses through ABA-mediated signal transduction pathways.
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Affiliation(s)
- Shuxin Zhang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
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27
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Bou-Torrent J, Salla-Martret M, Brandt R, Musielak T, Palauqui JC, Martínez-García JF, Wenkel S. ATHB4 and HAT3, two class II HD-ZIP transcription factors, control leaf development in Arabidopsis. PLANT SIGNALING & BEHAVIOR 2012; 7:1382-1387. [PMID: 22918502 PMCID: PMC3548853 DOI: 10.4161/psb.21824] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In response to plant proximity or canopy shade, plants can react by altering elongation growth and development. Several members of the class II homeodomain-leucine zipper (HD-ZIPII) transcription factor family have been shown to play an instrumental role in the responses to shade. HD-ZIP members of the class III (HD-ZIPIII), by contrast, are involved in basic patterning processes. We recently showed that REVOLUTA (REV), a member of the HD-ZIPIII family, directly and positively regulates the expression of several genes involved in shade-induced growth, such as those encoding HD-ZIPII factors HAT2, HAT3, ATHB2/HAT4 and ATHB4, and of the components of the auxin biosynthesis pathway YUCCA5 and TAA1. Furthermore, we could demonstrate a novel role for HD-ZIPIII in shade-induced promotion of growth. Here we show that besides responding to shade, ATHB4 and HAT3 have a critical role in establishing the dorso-ventral axis in cotyledons and developing leaves. Loss-of-function mutations in these two HD-ZIPII genes (athb4 hat3) results in severely abaxialized, entirely radialized leaves. Conversely, overexpression of HAT3 results in adaxialized leaf development. Taken together, our findings unravel a so far unappreciated role for an HD-ZIPII/HD-ZIPIII module required for dorso-ventral patterning of leaves. The finding that HD-ZIPII/HD-ZIPIII also function in shade avoidance suggests that this module is at the nexus of patterning and growth promotion.
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Affiliation(s)
- Jordi Bou-Torrent
- Centre for Research in Agricultural Genomics (CRAG); CSIC-IRTA-UAB-UB; Barcelona, Spain
| | - Mercè Salla-Martret
- Centre for Research in Agricultural Genomics (CRAG); CSIC-IRTA-UAB-UB; Barcelona, Spain
| | - Ronny Brandt
- Center for Plant Molecular Biology (ZMBP); University of Tübingen; Tübingen, Germany
| | - Thomas Musielak
- Center for Plant Molecular Biology (ZMBP); University of Tübingen; Tübingen, Germany
| | - Jean-Christophe Palauqui
- INRA Centre Versailles Grignon; Institut Jean Pierre Bourgin; UMR1318; INRA AgroParisTech; Versailles, France
| | - Jaime F. Martínez-García
- Centre for Research in Agricultural Genomics (CRAG); CSIC-IRTA-UAB-UB; Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA); Barcelona, Spain
| | - Stephan Wenkel
- Center for Plant Molecular Biology (ZMBP); University of Tübingen; Tübingen, Germany
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28
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Delatorre CA, Cohen Y, Liu L, Peleg Z, Blumwald E. The regulation of the SARK promoter activity by hormones and environmental signals. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2012; 193-194:39-47. [PMID: 22794917 DOI: 10.1016/j.plantsci.2012.05.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 05/09/2012] [Accepted: 05/10/2012] [Indexed: 06/01/2023]
Abstract
The Senescence Associated Receptor Protein Kinase (P(SARK)) promoter, fused to isopentenyltransferase (IPT) gene has been shown to promote drought tolerance in crops. We dissected P(SARK) in order to understand the various elements associated with its activation and suppression. The activity of P(SARK) was higher in mature and early senescing leaves, and abiotic stress induced its activity in mature leaves. Bioinformatics analysis suggests the interactions of multiple cis-acting elements in the control of P(SARK) activity. In vitro gel shift assays and yeast one hybrid system revealed interactions of P(SARK) with transcription factors related to abscisic acid and cytokinin response. Deletion analysis of P(SARK), fused to GUS-reporter gene was used to identify specific regions regulating transcription under senescence or during drought stress. Effects of exogenous hormonal treatments were characterized in entire plants and in leaf disk assays, and regions responsive to various hormones were defined. Our results indicate a complex interaction of plant hormones and additional factors modulating P(SARK) activity under stress resulting in a transient induction of expression.
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Affiliation(s)
- Carla A Delatorre
- Department of Plant Sciences, University of California, Davis, CA 95616, USA; Department of Crop Science, Agronomy School, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, RS, 91501970, Brazil.
| | - Yuval Cohen
- Department of Plant Sciences, University of California, Davis, CA 95616, USA; Department of Fruit Tree Sciences, Institute of Plant Sciences, Volcani Research Center (ARO), Bet Dagan, 50250, Israel.
| | - Li Liu
- Department of Plant Sciences, University of California, Davis, CA 95616, USA
| | - Zvi Peleg
- Department of Plant Sciences, University of California, Davis, CA 95616, USA
| | - Eduardo Blumwald
- Department of Plant Sciences, University of California, Davis, CA 95616, USA.
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29
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Walford SA, Wu Y, Llewellyn DJ, Dennis ES. Epidermal cell differentiation in cotton mediated by the homeodomain leucine zipper gene, GhHD-1. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 71:464-478. [PMID: 22443311 DOI: 10.1111/j.1365-313x.2012.05003.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Gossypium hirsutum L. (cotton) fibres are specialized trichomes a few centimetres in length that grow from the seed coat. Few genes directly involved in the differentiation of these epidermal cells have been identified. These include GhMYB25-like and GhMYB25, two related MYB transcription factors that regulate fibre cell initiation and expansion. We have also identified a putative homeodomain leucine zipper (HD-ZIP) transcription factor, GhHD-1, expressed in trichomes and early fibres that might play a role in cotton fibre initiation. Here, we characterize GhHD-1 homoeologues from tetraploid G. hirsutum and show, using reporter constructs and quantitative real-time PCR (qRT-PCR), that they are expressed predominantly in epidermal tissues during early fibre development, and in other tissues bearing epidermal trichomes. Silencing of GhHD-1 reduced trichome formation and delayed the timing of fibre initiation. Constitutive overexpression of GhHD-1 increased the number of fibres initiating on the seed, but did not affect leaf trichomes. Expression of GhHD-1 in cotton silenced for different fibre MYBs suggest that in ovules it acts downstream of GhMYB25-like, but is unaffected in GhMYB25- or GhMYB109-silenced plants. Microarray analysis of silencing and overexpression lines of GhHD-1 indicated that it potentially regulates the levels of ethylene and reactive oxidation species (ROS) through a WRKY transcription factor and calcium-signalling pathway genes to activate downstream genes necessary for cell expansion and elongation.
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30
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Deng F, Tu L, Tan J, Li Y, Nie Y, Zhang X. GbPDF1 is involved in cotton fiber initiation via the core cis-element HDZIP2ATATHB2. PLANT PHYSIOLOGY 2012; 158:890-904. [PMID: 22123900 PMCID: PMC3271776 DOI: 10.1104/pp.111.186742] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 11/21/2011] [Indexed: 05/18/2023]
Abstract
Cotton (Gossypium spp.) fiber cells are seed trichomes derived from the epidermal layer of the cotton seed coat. The molecular components responsible for regulating fiber cell differentiation have not been fully elucidated. A cotton PROTODERMAL FACTOR1 gene (GbPDF1) was found to be expressed preferentially during fiber initiation and early elongation, with highest accumulation in fiber cells 5 d post anthesis. PDF1 silencing caused retardation of fiber initiation and produced shorter fibers and lower lint percentage compared with the wild type, indicating that the gene is required for cotton fiber development. Further analysis showed that a higher accumulation of hydrogen peroxide occurred in the RNA interference transgenic cotton lines. Meanwhile, the expression of several genes related to ethylene and pectin synthesis or sugar transport during cotton fiber growth was found to be significantly reduced in the PDF1-suppressed cotton. Three proteins interacting with GbPDF1 in yeast and in planta might involve cellular signaling or metabolism. GbPDF1 promoter::GUS constructs in transgenic cotton were predominantly expressed in the epidermis of ovules and developing fibers. Progressive deletions of the GbPDF1 promoter showed that a 236-bp promoter fragment was sufficient for basal GbPDF1 transcription in cotton. Mutation of putative regulatory sequences showed that HDZIP2ATATHB2, an element within the fragment, was essential for PGbPDF1-1 expression. The binding activity between this cis-element and nuclear extracts from fiber-bearing cotton ovules at 5 d post anthesis was specific. We conclude that GbPDF1 plays a critical role together with interaction partners in hydrogen peroxide homeostasis and steady biosynthesis of ethylene and pectin during fiber development via the core cis-element HDZIP2ATATHB2.
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Affiliation(s)
| | | | | | | | | | - Xianlong Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
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31
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Ruberti I, Sessa G, Ciolfi A, Possenti M, Carabelli M, Morelli G. Plant adaptation to dynamically changing environment: the shade avoidance response. Biotechnol Adv 2011; 30:1047-58. [PMID: 21888962 DOI: 10.1016/j.biotechadv.2011.08.014] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 07/23/2011] [Accepted: 08/16/2011] [Indexed: 11/30/2022]
Abstract
The success of competitive interactions between plants determines the chance of survival of individuals and eventually of whole plant species. Shade-tolerant plants have adapted their photosynthesis to function optimally under low-light conditions. These plants are therefore capable of long-term survival under a canopy shade. In contrast, shade-avoiding plants adapt their growth to perceive maximum sunlight and therefore rapidly dominate gaps in a canopy. Daylight contains roughly equal proportions of red and far-red light, but within vegetation that ratio is lowered as a result of red absorption by photosynthetic pigments. This light quality change is perceived through the phytochrome system as an unambiguous signal of the proximity of neighbors resulting in a suite of developmental responses (termed the shade avoidance response) that, when successful, result in the overgrowth of those neighbors. Shoot elongation induced by low red/far-red light may confer high relative fitness in natural dense communities. However, since elongation is often achieved at the expense of leaf and root growth, shade avoidance may lead to reduction in crop plant productivity. Over the past decade, major progresses have been achieved in the understanding of the molecular basis of shade avoidance. However, uncovering the mechanisms underpinning plant response and adaptation to changes in the ratio of red to far-red light is key to design new strategies to precise modulate shade avoidance in time and space without impairing the overall crop ability to compete for light.
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Affiliation(s)
- I Ruberti
- Institute of Molecular Biology and Pathology, National Research Council, Piazzalle Aldo Moro 5, Rome, Italy.
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32
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Li Y, Swaminathan K, Hudson ME. Rapid, organ-specific transcriptional responses to light regulate photomorphogenic development in dicot seedlings. PLANT PHYSIOLOGY 2011; 156:2124-40. [PMID: 21653191 PMCID: PMC3149948 DOI: 10.1104/pp.111.179416] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 05/31/2011] [Indexed: 05/20/2023]
Abstract
The dicotyledon seedling undergoes organ-specific photomorphogenic development when exposed to light. The cotyledons open and expand, the apical hook opens, and the hypocotyl ceases to elongate. Using the large and easily dissected seedlings of soybean (Glycine max 'Williams 82'), we show that genes involved in photosynthesis and its regulation dominate transcripts specific to the cotyledon, even in etiolated seedlings. Genes for cell wall biosynthesis and metabolism are expressed at higher levels in the hypocotyl, while examination of genes expressed at higher levels in the hook region (including the shoot apical meristem) reveals genes involved in cell division and protein turnover. The early transcriptional events in these three organs in response to a 1-h treatment of far-red light are highly distinctive. Not only are different regulatory genes rapidly regulated by light in each organ, but the early-responsive genes in each organ contain a distinctive subset of known light-responsive cis-regulatory elements. We detected specific light-induced gene expression for the root phototropism gene RPT2 in the apical hook and also phenotypes in Arabidopsis (Arabidopsis thaliana) rpt2 mutants demonstrating that the gene is necessary for normal photomorphogenesis in the seedling apex. Significantly, expression of the RPT2 promoter fused to a β-glucuronidase reporter gene shows differential expression across the hook region. We conclude that organ-specific, light-responsive transcriptional networks are active early in photomorphogenesis in the aerial parts of dicotyledon seedlings.
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Affiliation(s)
| | | | - Matthew E. Hudson
- Department of Crop Sciences (Y.L., K.S., M.E.H.) and Energy Biosciences Institute and Institute for Genomic Biology (K.S., M.E.H.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
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33
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Harris JC, Hrmova M, Lopato S, Langridge P. Modulation of plant growth by HD-Zip class I and II transcription factors in response to environmental stimuli. THE NEW PHYTOLOGIST 2011; 190:823-837. [PMID: 21517872 DOI: 10.1111/j.1469-8137.2011.03733.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Plant development is adapted to changing environmental conditions for optimizing growth. This developmental adaptation is influenced by signals from the environment, which act as stimuli and may include submergence and fluctuations in water status, light conditions, nutrient status, temperature and the concentrations of toxic compounds. The homeodomain-leucine zipper (HD-Zip) I and HD-Zip II transcription factor networks regulate these plant growth adaptation responses through integration of developmental and environmental cues. Evidence is emerging that these transcription factors are integrated with phytohormone-regulated developmental networks, enabling environmental stimuli to influence the genetically preprogrammed developmental progression. Dependent on the prevailing conditions, adaptation of mature and nascent organs is controlled by HD-Zip I and HD-Zip II transcription factors through suppression or promotion of cell multiplication, differentiation and expansion to regulate targeted growth. In vitro assays have shown that, within family I or family II, homo- and/or heterodimerization between leucine zipper domains is a prerequisite for DNA binding. Further, both families bind similar 9-bp pseudopalindromic cis elements, CAATNATTG, under in vitro conditions. However, the mechanisms that regulate the transcriptional activity of HD-Zip I and HD-Zip II transcription factors in vivo are largely unknown. The in planta implications of these protein-protein associations and the similarities in cis element binding are not clear.
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Affiliation(s)
- John C Harris
- Australian Centre for Plant Functional Genomics, PMB 1, Glen Osmond, SA 5064, Australia
| | - Maria Hrmova
- Australian Centre for Plant Functional Genomics, PMB 1, Glen Osmond, SA 5064, Australia
| | - Sergiy Lopato
- Australian Centre for Plant Functional Genomics, PMB 1, Glen Osmond, SA 5064, Australia
| | - Peter Langridge
- Australian Centre for Plant Functional Genomics, PMB 1, Glen Osmond, SA 5064, Australia
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Dezar CA, Giacomelli JI, Manavella PA, Ré DA, Alves-Ferreira M, Baldwin IT, Bonaventure G, Chan RL. HAHB10, a sunflower HD-Zip II transcription factor, participates in the induction of flowering and in the control of phytohormone-mediated responses to biotic stress. JOURNAL OF EXPERIMENTAL BOTANY 2011; 62:1061-76. [PMID: 21030388 DOI: 10.1093/jxb/erq339] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The transcription factor HAHB10 belongs to the sunflower (Helianthus annuus) HD-Zip II subfamily and it has been previously associated with the induction of flowering. In this study it is shown that HAHB10 is expressed in sunflower leaves throughout the vegetative stage and in stamens during the reproductive stage. In short-day inductive conditions the expression of this gene is induced in shoot apexes together with the expression of the flowering genes HAFT and HAAP1. Transgenic Arabidopsis plants expressing HAHB10 cDNA under regulation either by its own promoter or by cauliflower mosaic virus (CaMV) 35S exhibited an early flowering phenotype. This phenotype was completely reverted in a non-inductive light regime, indicating a photoperiod-dependent action for this transcription factor. Gene expression profiling of Arabidopsis plants constitutively expressing HAHB10 indicated that specific flowering transition genes such as FT, FUL, and SEP3 were induced several fold, whereas genes related to biotic stress responses, such as PR1, PR2, ICS1, AOC1, EDS5, and PDF1-2a, were repressed. The expression of HAHB10 and of the flowering genes HASEP3 and HAFT was up-regulated by both salicylic acid (SA) treatment and infection with a virulent strain of Pseudomonas syringae. Basal SA and jasmonic acid (JA) levels in Arabidopsis plants ectopically expressing HAHB10 were similar to those of control plants; however, SA levels differentially increased in the transgenic plants after wounding and infection with P. syringae while JA levels differentially decreased. Taken together, the results indicated that HAHB10 participates in two different processes in plants: the transition from the vegetative to the flowering stage via the induction of specific flowering transition genes and the accumulation of phytohormones upon biotic stresses.
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Affiliation(s)
- Carlos A Dezar
- Instituto de Agrobiotecnología del Litoral, Universidad Nacional del Litoral, CONICET, CC 242 Ciudad Universitaria, 3000, Santa Fe, Argentina
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Neelakandan AK, Nguyen HTM, Kumar R, Tran LSP, Guttikonda SK, Quach TN, Aldrich DL, Nes WD, Nguyen HT. Molecular characterization and functional analysis of Glycine max sterol methyl transferase 2 genes involved in plant membrane sterol biosynthesis. PLANT MOLECULAR BIOLOGY 2010; 74:503-18. [PMID: 20865301 DOI: 10.1007/s11103-010-9692-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2010] [Accepted: 09/11/2010] [Indexed: 05/29/2023]
Abstract
Sterol C24 methyltransferase (SMT2) genes governing the pattern of phytosterols synthesized in higher plants have been studied in Glycine seedlings and wild-type and engineered Arabidopsis thaliana plants. The SMT2 genes of soybean (SMT2-1 and SMT2-2) previously cloned and characterized (Neelakandan et al. 2009) were shown to complement the SMT deficient cvp1 mutant Arabidopsis plants, consistent with their role in regulation of 24-alkyl sterol-controlled plant physiology. Further analysis of these genes showed that environmental cues, including dehydration, cold, and abscisic acid induced differential changes in transcript levels of the SMT2 during soybean seedling growth. Sterol analyses of transgenic Arabidopsis seeds originating in variant constructs of AtHMGR1, GmSMT1, and GmSMT2 engineered in seeds showed relevant modifications in the ratio of 24-methyl to 24-ethyl sterol in the direction of sitosterol formation. To provide insight into the structural features of the sterol gene that affects transcript regulation, the upstream promoter sequences of soybean SMT2 genes were cloned and characterized. Sequence analysis revealed several important cis-elements and transcription factor binding sites. The analysis of promoter-GUS fusions in transgenic Arabidopsis plants revealed shared and distinct expression features in different developmental stages and tissues. The data are interpreted to imply that SMT2 is an important contributor to normal plant growth and development.
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Affiliation(s)
- Anjanasree K Neelakandan
- Division of Plant Sciences and National Center for Soybean Biotechnology, University of Missouri, Columbia, MO 65211, USA
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Kagale S, Links MG, Rozwadowski K. Genome-wide analysis of ethylene-responsive element binding factor-associated amphiphilic repression motif-containing transcriptional regulators in Arabidopsis. PLANT PHYSIOLOGY 2010; 152:1109-34. [PMID: 20097792 PMCID: PMC2832246 DOI: 10.1104/pp.109.151704] [Citation(s) in RCA: 225] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Accepted: 01/17/2010] [Indexed: 05/17/2023]
Abstract
The ethylene-responsive element binding factor-associated amphiphilic repression (EAR) motif is a transcriptional regulatory motif identified in members of the ethylene-responsive element binding factor, C2H2, and auxin/indole-3-acetic acid families of transcriptional regulators. Sequence comparison of the core EAR motif sites from these proteins revealed two distinct conservation patterns: LxLxL and DLNxxP. Proteins containing these motifs play key roles in diverse biological functions by negatively regulating genes involved in developmental, hormonal, and stress signaling pathways. Through a genome-wide bioinformatics analysis, we have identified the complete repertoire of the EAR repressome in Arabidopsis (Arabidopsis thaliana) comprising 219 proteins belonging to 21 different transcriptional regulator families. Approximately 72% of these proteins contain a LxLxL type of EAR motif, 22% contain a DLNxxP type of EAR motif, and the remaining 6% have a motif where LxLxL and DLNxxP are overlapping. Published in vitro and in planta investigations support approximately 40% of these proteins functioning as negative regulators of gene expression. Comparative sequence analysis of EAR motif sites and adjoining regions has identified additional preferred residues and potential posttranslational modification sites that may influence the functionality of the EAR motif. Homology searches against protein databases of poplar (Populus trichocarpa), grapevine (Vitis vinifera), rice (Oryza sativa), and sorghum (Sorghum bicolor) revealed that the EAR motif is conserved across these diverse plant species. This genome-wide analysis represents the most extensive survey of EAR motif-containing proteins in Arabidopsis to date and provides a resource enabling investigations into their biological roles and the mechanism of EAR motif-mediated transcriptional regulation.
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Sorin C, Salla-Martret M, Bou-Torrent J, Roig-Villanova I, Martínez-García JF. ATHB4, a regulator of shade avoidance, modulates hormone response in Arabidopsis seedlings. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 59:266-77. [PMID: 19392702 DOI: 10.1111/j.1365-313x.2009.03866.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Plants sense the presence of competing neighboring vegetation as a change in light quality: i.e. they sense the reduced ratio of red light to far-red light. The responses to shade are generally referred to as the shade avoidance syndrome (SAS), and involve various developmental changes intended to outgrow or outcompete the neighboring plants. Here, we analyze the function of ATHB4, a gene encoding a homeodomain-leucine zipper (HD-Zip) class-II transcription factor from Arabidopsis thaliana, the expression of which is rapidly and directly upregulated after proximity perception by the phytochrome photoreceptors. ATHB4 acts redundantly with other members of the HD-Zip class-II transcription factors. The expression of these genes is regulated by other members of the same class, forming a small transcriptional network of factors in which homeostasis is mutually controlled. Our results suggest that some members of this small gene subfamily can modulate SAS responses by controlling auxin, brassinosteroid and gibberellin molecular and/or physiological responsiveness. In particular, we propose ATHB4 as a new shade signaling component that participates in integrating shade perception and hormone-mediated growth.
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Affiliation(s)
- Céline Sorin
- Center for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB, c. Jordi Girona, 18-26, 08034-Barcelona, Spain
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Ciarbelli AR, Ciolfi A, Salvucci S, Ruzza V, Possenti M, Carabelli M, Fruscalzo A, Sessa G, Morelli G, Ruberti I. The Arabidopsis homeodomain-leucine zipper II gene family: diversity and redundancy. PLANT MOLECULAR BIOLOGY 2008; 68:465-78. [PMID: 18758690 DOI: 10.1007/s11103-008-9383-8] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Accepted: 07/23/2008] [Indexed: 05/20/2023]
Abstract
The Arabidopsis genome contains 10 genes belonging to the HD-Zip II family including ATHB2 and HAT2. Previous work has shown that ATHB2 is rapidly and strongly induced by light quality changes that provoke the shade avoidance response whereas HAT2 expression responds to auxin. Here, we present a genome-wide analysis of the HD-Zip II family. Phylogeny reconstruction revealed that almost all of the HD-Zip II genes can be subdivided into 4 clades (alpha-delta), each clade comprising 2-3 paralogs. Gene expression studies demonstrated that all the gamma and delta genes are regulated by light quality changes. Kinetics of induction, low R/FR/high R/FR reversibility and auxin response analyses strongly suggested that HAT1, HAT3 and ATHB4, as ATHB2, are under the control of the phytochrome system whereas HAT2 is up-regulated by low R/FR as a consequence of the induction of the auxin signaling pathway provoked by FR-rich light. Root and shoot digital in situ revealed that gamma and delta genes are also tightly regulated during plant development with both distinct and overlapping patterns. Phenotypes of gain of function and dominant negative lines demonstrated that one or more of the HD-Zip II gamma genes negatively regulate cell proliferation during leaf development in a high R/FR light environment. Finally, target gene analysis using a chimeric transcription factor (HD-Zip2-V-G), known to activate ATHB2 target genes in a glucocorticoid-dependent manner, revealed that all the 10 HD-Zip II genes can be recognized by the HD-Zip 2 domain in vivo, implying an intricate negative feedback network.
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Agalou A, Purwantomo S, Overnäs E, Johannesson H, Zhu X, Estiati A, de Kam RJ, Engström P, Slamet-Loedin IH, Zhu Z, Wang M, Xiong L, Meijer AH, Ouwerkerk PBF. A genome-wide survey of HD-Zip genes in rice and analysis of drought-responsive family members. PLANT MOLECULAR BIOLOGY 2008; 66:87-103. [PMID: 17999151 DOI: 10.1007/s11103-007-9255-7] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2007] [Accepted: 10/25/2007] [Indexed: 05/20/2023]
Abstract
The homeodomain leucine zipper (HD-Zip) genes encode transcription factors that have diverse functions in plant development and have often been implicated in stress adaptation. The HD-Zip genes are the most abundant group of homeobox (HB) genes in plants and do not occur in other eukaryotes. This paper describes the complete annotation of the HD-Zip families I, II and III from rice and compares these gene families with Arabidopsis in a phylogeny reconstruction. Orthologous pairs of rice and Arabidopsis HD-Zip genes were predicted based on neighbour joining and maximum parsimony (MP) trees with support of conserved intron-exon organization. Additionally, a number of HD-Zip genes appeared to be unique to rice. Searching of EST and cDNA databases and expression analysis using RT-PCR showed that 30 out of 31 predicted rice HD-Zip genes are expressed. Most HD-Zip genes were broadly expressed in mature plants and seedlings, but others showed more organ specific patterns. Like in Arabidopsis and other dicots, a subset of the rice HD-Zip I and II genes was found to be regulated by drought stress. We identified both drought-induced and drought-repressed HD-Zip genes and demonstrate that these genes are differentially regulated in drought-sensitive versus drought-tolerant rice cultivars. The drought-repressed HD-Zip family I gene, Oshox4, was selected for promoter-GUS analysis, showing that drought-responsiveness of Oshox4 is controlled by the promoter and that Oshox4 expression is predominantly vascular-specific. Loss-of-function analysis of Oshox4 revealed no specific phenotype, but overexpression analysis suggested a role for Oshox4 in elongation and maturation processes.
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Affiliation(s)
- Adamantia Agalou
- Institute of Biology, Clusius Laboratory, Leiden University, PO Box 9505, 2300 RA, Leiden, The Netherlands
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Roig-Villanova I, Bou-Torrent J, Galstyan A, Carretero-Paulet L, Portolés S, Rodríguez-Concepción M, Martínez-García JF. Interaction of shade avoidance and auxin responses: a role for two novel atypical bHLH proteins. EMBO J 2007; 26:4756-67. [PMID: 17948056 PMCID: PMC2080812 DOI: 10.1038/sj.emboj.7601890] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2007] [Accepted: 09/24/2007] [Indexed: 11/08/2022] Open
Abstract
Plants sense the presence of potentially competing nearby individuals as a reduction in the red to far-red ratio of the incoming light. In anticipation of eventual shading, a set of plant responses known as the shade avoidance syndrome (SAS) is initiated soon after detection of this signal by the phytochrome photoreceptors. Here we analyze the function of PHYTOCHROME RAPIDLY REGULATED1 (PAR1) and PAR2, two Arabidopsis thaliana genes rapidly upregulated after simulated shade perception. These genes encode two closely related atypical basic helix-loop-helix proteins with no previously assigned function in plant development. Using reverse genetic approaches, we show that PAR1 and PAR2 act in the nucleus to broadly control plant development, acting as negative regulators of a variety of SAS responses, including seedling elongation and photosynthetic pigment accumulation. Molecularly, PAR1 and PAR2 act as direct transcriptional repressors of two auxin-responsive genes, SMALL AUXIN UPREGULATED15 (SAUR15) and SAUR68. Additional results support that PAR1 and PAR2 function in integrating shade and hormone transcriptional networks, rapidly connecting phytochrome-sensed light changes with auxin responsiveness.
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Affiliation(s)
- Irma Roig-Villanova
- Laboratori de Genètica Molecular Vegetal Consorci CSIC-IRTA, Departament de Genètica Molecular, Barcelona, Spain
| | - Jordi Bou-Torrent
- Laboratori de Genètica Molecular Vegetal Consorci CSIC-IRTA, Departament de Genètica Molecular, Barcelona, Spain
| | - Anahit Galstyan
- Laboratori de Genètica Molecular Vegetal Consorci CSIC-IRTA, Departament de Genètica Molecular, Barcelona, Spain
| | - Lorenzo Carretero-Paulet
- Laboratori de Genètica Molecular Vegetal Consorci CSIC-IRTA, Departament de Genètica Molecular, Barcelona, Spain
| | - Sergi Portolés
- Laboratori de Genètica Molecular Vegetal Consorci CSIC-IRTA, Departament de Genètica Molecular, Barcelona, Spain
| | - Manuel Rodríguez-Concepción
- Laboratori de Genètica Molecular Vegetal Consorci CSIC-IRTA, Departament de Genètica Molecular, Barcelona, Spain
- Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Barcelona, Spain
| | - Jaime F Martínez-García
- Laboratori de Genètica Molecular Vegetal Consorci CSIC-IRTA, Departament de Genètica Molecular, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
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Ariel FD, Manavella PA, Dezar CA, Chan RL. The true story of the HD-Zip family. TRENDS IN PLANT SCIENCE 2007; 12:419-26. [PMID: 17698401 DOI: 10.1016/j.tplants.2007.08.003] [Citation(s) in RCA: 355] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2006] [Revised: 05/24/2007] [Accepted: 08/03/2007] [Indexed: 05/04/2023]
Abstract
The HD-Zip family of transcription factors is unique to the plant kingdom. These proteins exhibit the singular combination of a homeodomain with a leucine zipper acting as a dimerization motif. They can be classified into four subfamilies, according to a set of distinctive features that include DNA-binding specificities, gene structures, additional common motifs and physiological functions. Some HD-Zip proteins participate in organ and vascular development or meristem maintenance. Others mediate the action of hormones or are involved in responses to environmental conditions. Here, we review recent data for this family of transcription factors from a wide variety of plant species to unravel their crucial role in plant development.
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Affiliation(s)
- Federico D Ariel
- Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, CONICET, CC 242 Ciudad Universitaria, 3000, Santa Fe, Argentina
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42
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Abstract
Plants have evolved complex and sophisticated transcriptional networks that mediate developmental changes in response to light. These light-regulated processes include seedling photomorphogenesis, seed germination and the shade-avoidance and photoperiod responses. Understanding the components and hierarchical structure of the transcriptional networks that are activated during these processes has long been of great interest to plant scientists. Traditional genetic and molecular approaches have proved powerful in identifying key regulatory factors and their positions within these networks. Recent genomic studies have further revealed that light induces massive reprogramming of the plant transcriptome, and that the early light-responsive genes are enriched in transcription factors. These combined approaches provide new insights into light-regulated transcriptional networks.
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Affiliation(s)
- Yuling Jiao
- Department of Molecular, Cellular and Developmental Biology, 165 Prospect Street, Yale University, New Haven, Connecticut 06520-8104, USA
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Taniguchi M, Sasaki N, Tsuge T, Aoyama T, Oka A. ARR1 directly activates cytokinin response genes that encode proteins with diverse regulatory functions. PLANT & CELL PHYSIOLOGY 2007; 48:263-77. [PMID: 17202182 DOI: 10.1093/pcp/pcl063] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Plant cells respond to cytokinins by changing their gene expression patterns. The histidyl-aspartyl (His-Asp) phosphorelay mediates the signal from cytokinin receptors to type-B response regulators including ARR1, which transactivate cytokinin primary response genes. However, the overall architecture of the signal cascade leading to cytokinin-responsive phenomena is still unclear, mainly because it is not known how the His-Asp phosphorelay is connected to downstream phenomena. To reveal events immediately downstream from the phosphorelay-mediated transcriptional activation, we searched for direct-target genes of ARR1 by exploiting ARR1DeltaDDK-GR, a chimeric transcription factor that transactivates ARR1 direct-target genes in transgenic plants by glucocorticoid induction. We identified 23 direct-target genes, most of which were found to be cytokinin primary response genes. The arr1-1 mutation clearly affected the primary response in at least 17 genes, meaning that they respond primarily to cytokinins through the function of ARR1. The 17 genes encode proteins with diverse functions, including type-A response regulators, cytokinin metabolic enzymes and putative disease resistance response proteins. These results provide novel evidence indicating that the His-Asp phosphorelay is connected to diverse regulatory levels of cytokinin-responsive phenomena through ARR1 direct-target genes.
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Mahalingam R, Jambunathan N, Gunjan SK, Faustin E, Weng H, Ayoubi P. Analysis of oxidative signalling induced by ozone in Arabidopsis thaliana. PLANT, CELL & ENVIRONMENT 2006; 29:1357-71. [PMID: 17080957 DOI: 10.1111/j.1365-3040.2006.01516.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We are using acute ozone as an elicitor of endogenous reactive oxygen species (ROS) to understand oxidative signalling in Arabidopsis. Temporal patterns of ROS following a 6 h exposure to 300 nL L(-1) of ozone in ozone-sensitive Wassilewskija (Ws-0) ecotype showed a biphasic ROS burst with a smaller peak at 4 h and a larger peak at 16 h. This was accompanied by a nitric oxide (NO) burst that peaked at 9 h. An analysis of antioxidant levels showed that both ascorbate (AsA) and glutathione (GSH) were at their lowest levels, when ROS levels were high in ozone-stressed plants. Whole genome expression profiling analysis at 1, 4, 8, 12 and 24 h after initiation of ozone treatment identified 371 differentially expressed genes. Early induction of proteolysis and hormone-responsive genes indicated that an oxidative cell death pathway was triggered rapidly. Down-regulation of genes involved in carbon utilization, energy pathways and signalling suggested an inefficient defense response. Comparisons with other large-scale expression profiling studies indicated some overlap between genes induced by ethylene and ozone, and a significant overlap between genes repressed by ozone and methyl jasmonate treatment. Further, analysis of cis elements in the promoters of ozone-responsive genes also supports the view that phytohormones play a significant role in ozone-induced cell death.
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Deng X, Phillips J, Bräutigam A, Engström P, Johannesson H, Ouwerkerk PBF, Ruberti I, Salinas J, Vera P, Iannacone R, Meijer AH, Bartels D. A homeodomain leucine zipper gene from Craterostigma plantagineum regulates abscisic acid responsive gene expression and physiological responses. PLANT MOLECULAR BIOLOGY 2006; 61:469-89. [PMID: 16830180 DOI: 10.1007/s11103-006-0023-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Accepted: 02/09/2006] [Indexed: 05/04/2023]
Abstract
A subset of homeodomain leucine zipper proteins (HDZip) play a role in regulating adaptation responses including developmental adjustment to environmental cues in plants. Here we report the structural and functional characterisation of a dehydration responsive nuclear-targeted HDZip transcriptional regulator, CpHB-7. DNA-protein interaction studies suggest that CDeT6-19, a known ABA and dehydration responsive dehydrin gene, is a potential target gene of CpHB-7 in the desiccation-tolerant plant Craterostigma plantagineum. Transgenic plants that ectopically express CpHB-7 display reduced sensitivity towards ABA during seed germination and stomatal closure. Expression analysis reveals that genes with induced or repressed expression in CpHB-7 ectopic expression lines are either mostly repressed or induced by ABA, drought or salt treatment respectively, thus demonstrating that CpHB-7 modifies ABA-responsive gene expression as a negative regulator. CpHB-7 gene expression is also linked to early organ development, leading to the suggestion that CpHB-7 is functionally similar to the Arabidopsis transcription factor, ATHB-6.
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Affiliation(s)
- Xin Deng
- Max-Planck-Institut für Züchtungsforschung, Carl-von-Linné-Weg 10, Cologne D-50829, Germany
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Baudry A, Caboche M, Lepiniec L. TT8 controls its own expression in a feedback regulation involving TTG1 and homologous MYB and bHLH factors, allowing a strong and cell-specific accumulation of flavonoids in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 46:768-79. [PMID: 16709193 DOI: 10.1111/j.1365-313x.2006.02733.x] [Citation(s) in RCA: 207] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The control of TT8 expression was investigated in this study, and it was demonstrated that it constitutes a major regulatory step in the specific activation of the expression of flavonoid structural genes. First, the GUS activity generated in planta from a TT8::uidA construct revealed cell-specific activation of the TT8 promoter consistent with the known involvement of the TT8 bHLH factor in proanthocyanidin, anthocyanin and mucilage biosynthesis. Moreover, the activity of this reporter construct was strongly affected in ttg1, TT2 overexpressers (OE), and PAP1-OE, suggesting interplay between TT2, PAP1, TTG1 and the activation of the TT8 promoter in planta. To further investigate the mechanisms involved, we used 35S::TT2-GR and 35S::TTG1-GR transgenic plants (expressing fusion proteins with the glucocorticoid receptor), as well as one-hybrid experiments, to determine the direct effect of these factors on TT8 expression. Interestingly, in vivo binding of TT2 and PAP1 to the TT8 promoter was dependent on the simultaneous expression of TT8 or the homologous bHLH factors GL3 and EGL3. Consistent with these results, the activity of the TT8::uidA reporter was strongly affected in the seed endothelium of a tt8 mutant. Similarly, a strong decrease in the level of TT8 mRNA was detected in the siliques of a gl3 x egl3 mutant and in plants that express a dominant negative form of the PAP1 protein, suggesting that TT8 expression is controlled by different combinations of MYB and bHLH factors in planta. The importance of this positive feedback mechanism in the strong and specific induction of proanthocyanidin biosynthesis in the seed coat of Arabidopsis thaliana is discussed.
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Affiliation(s)
- Antoine Baudry
- Seed Biology Laboratory, UMR 204 INRA/INAPG, Jean-Pierre Bourgin Institute, Route de Saint-Cyr, 78026 Versailles Cedex, France
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47
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Roig-Villanova I, Bou J, Sorin C, Devlin PF, Martínez-García JF. Identification of primary target genes of phytochrome signaling. Early transcriptional control during shade avoidance responses in Arabidopsis. PLANT PHYSIOLOGY 2006; 141:85-96. [PMID: 16565297 PMCID: PMC1459307 DOI: 10.1104/pp.105.076331] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The phytochrome (phy) photoreceptors modulate plant development after perception of light. Upon illumination of etiolated seedlings, phys initiate a transcriptional cascade by directly transducing light signals to the promoters of genes encoding regulators of morphogenesis. In light-grown plants, however, little is known about the transcriptional cascade modulated by phys in response to changes in light. The phy entry points in this cascade are completely unknown. We are particularly interested in the shade avoidance syndrome (SAS). Here we describe a subset of six genes whose expression is rapidly modulated by phys during both deetiolation and SAS in Arabidopsis (Arabidopsis thaliana). Using cycloheximide, we provide evidence that four of these phy rapidly regulated (PAR) genes are direct targets of phy signaling during SAS, revealing these genes as upstream components of the transcriptional cascade. Promoter-beta-glucuronidase fusions confirmed that PAR genes are photoregulated at the transcriptional level. Analysis of gene expression in light signal transduction mutants showed that COP1 and DET1 (but not DET2 or HY5) play a role in modulating PAR expression in response to shade in light-grown seedlings. Moreover, genetic analyses showed that one of the genes identified as a direct target of phy signaling was phy-interacting factor 3-like-1 (PIL1). PIL1 has previously been implicated in SAS in response to transient shade, but we show here that it also plays a key role in response to long-term shade. The action of PIL1 was particularly apparent in a phyB background, suggesting an important negative role for PIL1 under dense vegetation canopies.
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Affiliation(s)
- Irma Roig-Villanova
- Departament de Genètica Molecular, Institut de Biologia Molecular de Barcelona, Consorci CSIC-IRTA, 08034 Barcelona, Spain
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Rueda EC, Dezar CA, Gonzalez DH, Chan RL. Hahb-10, a sunflower homeobox-leucine zipper gene, is regulated by light quality and quantity, and promotes early flowering when expressed in Arabidopsis. PLANT & CELL PHYSIOLOGY 2005; 46:1954-63. [PMID: 16215272 DOI: 10.1093/pcp/pci210] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Homeodomain-leucine zipper proteins constitute a family of transcription factors found only in plants. Expression patterns of the sunflower homeobox-leucine zipper gene Hahb-10 (Helianthus annuus homeobox-10), that belongs to the HD-Zip II subfamily, were analysed. Northern blots showed that Hahb-10 is expressed primarily in mature leaves, although expression is clearly detectable in younger leaves and also in stems. Considerably higher expression levels were detected in etiolated seedlings compared with light-grown seedlings. Induction of Hahb-10 expression was observed when seedlings were subjected to treatment with gibberellins. Transgenic Arabidopsis thaliana plants that express Hahb-10 under the 35S cauliflower mosaic virus promoter show special phenotypic characteristics such as darker cotyledons and planar leaves. A reduction in the life cycle of about 25% allowing earlier seed collection was also observed, and this phenomenon is clearly related to a shortened flowering time. When the number of plants per pot increased, the difference in developmental rate between transgenic and non-transformed individuals became larger. After gibberellin treatment, the relative difference in life cycle duration was considerably reduced. Several light-regulated genes have been tested as possible target genes of Hahb-10. One of them, PsbS, shows a different response to illumination conditions in transgenic plants compared with the response in wild-type plants while the other genes behave similarly in both genotypes. We propose that Hahb-10 functions in a signalling cascade(s) that control(s) plant responses to light quality and quantity, and may also be involved in gibberellin transduction pathways.
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Affiliation(s)
- Eva C Rueda
- Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, CC 242 Paraje El Pozo, 3000 Santa Fe, Argentina
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Wang YJ, Li YD, Luo GZ, Tian AG, Wang HW, Zhang JS, Chen SY. Cloning and characterization of an HDZip I gene GmHZ1 from soybean. PLANTA 2005; 221:831-43. [PMID: 15754189 DOI: 10.1007/s00425-005-1496-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Accepted: 01/29/2005] [Indexed: 05/24/2023]
Abstract
By using cDNA-AFLP, we analyzed a recombinant inbred line population of soybean that was derived from a soybean mosaic virus (SMV) resistant cultivar Kefeng No.1 and a susceptible cultivar Nannong 1138-2. One hundred and eight fragments showing polymorphism between SMV resistant and susceptible pools were identified. One fragment w27 was 96 bp in length and showed homology to homeobox ggth with a coding region of 738 bp, encoding a protein of 245 amino acids. The genomic sequence analysis defined an intron of 521 bp in the coding region. GmHZ1 was characterized by the presence of a homeodomain (HD) with a closely linked leucine zipper motif (Zip). Southern blot analysis indicated that there was a single copy of GmHZ1 in the soybean genome. When inoculated with SMV strain N3, resistant and susceptible varieties showed reduced and increased expression of the GmHZ1, respectively. The fusion protein of GmHZ1 with GFP was targeted only in nucleus. Yeast two hybrid studies revealed that the GmHZ1 had transcriptional activation activity and can form homodimer. GmHZ1 can bind two 9-bp pseudopalindromic elements (CAAT(A/T)ATTG and CAAT(C/G)ATTG) with different affinity. Using GUS as a reporter gene, GmHZ1 was proved to be a transcriptional activator and enhanced GUS expression by binding with the two elements in plant cells. These results indicate that the GmHZ1 may have a transcriptional activator function in plant response to SMV infection.
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Affiliation(s)
- Yong-Jun Wang
- The National Plant Gene Reasearch Center (Beijing), National Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
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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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