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Vogel K, Isono E. Deubiquitylating enzymes in Arabidopsis thaliana endocytic protein degradation. Biochem Soc Trans 2024; 52:291-299. [PMID: 38174770 DOI: 10.1042/bst20230561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/05/2024]
Abstract
The regulation of ubiquitylation is key for plant growth and development, in which the activities of ubiquitylating enzymes as well as deubiquitylating enzymes (DUBs) determine the stability or function of the modified proteins. In contrast with ubiquitylating enzymes, there are less numbers of DUBs. DUBs can be classified into seven protein families according to the amino acid sequence of their catalytic domains. The catalytic domains of animal and plant DUB families show high homology, whereas the regions outside of the catalytic site can vary a lot. By hydrolyzing the ubiquitin molecules from ubiquitylated proteins, DUBs control ubiquitin-dependent selective protein degradation pathways such as the proteasomal-, autophagic-, and endocytic degradation pathways. In the endocytic degradation pathway, DUBs can modulate the endocytic trafficking and thus the stability of plasma membrane proteins including receptors and transporters. To date, three DUB families were shown to control the endocytic degradation pathway namely associated molecule with the SH3 domain of STAM (AMSH) 3, ubiquitin-specific protease (UBP) 12 and UBP13, and ovarian tumor protease (OTU) 11 and OTU12. In this review we will summarize the activity, molecular functions, and target protein of these DUBs and how they contribute to the environmental response of plants.
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Affiliation(s)
- Karin Vogel
- Department of Biology, University of Konstanz, Universitätsstraße 10, D-78464 Konstanz, Germany
| | - Erika Isono
- Department of Biology, University of Konstanz, Universitätsstraße 10, D-78464 Konstanz, Germany
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Liu Z, Wang L, Li Y, Zhu J, Li Z, Chen L, Li H, Shi T, Yao P, Bi Z, Sun C, Bai J, Zhang J, Liu Y. Genome-wide analysis of the U-box E3 ligases gene family in potato (Solanum tuberosum L.) and overexpress StPUB25 enhance drought tolerance in transgenic Arabidopsis. BMC Genomics 2024; 25:10. [PMID: 38166714 PMCID: PMC10759479 DOI: 10.1186/s12864-023-09890-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 12/11/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND Plant U-box (PUB) E3 ubiquitin ligases have vital effects on various biological processes. Therefore, a comprehensive and systematic identification of the members of the U-box gene family in potato will help to understand the evolution and function of U-box E3 ubiquitin ligases in plants. RESULTS This work identified altogether 74 PUBs in the potato (StPUBs) and examined their gene structures, chromosomal distributions, and conserved motifs. There were seventy-four StPUB genes on ten chromosomes with diverse densities. As revealed by phylogenetic analysis on PUBs within potato, Arabidopsis, tomato (Solanum lycopersicum), cabbage (Brassica oleracea), rice (Oryza sativa), and corn (Zea mays), were clustered into eight subclasses (C1-C8). According to synteny analysis, there were 40 orthologous StPUB genes to Arabidopsis, 58 to tomato, 28 to cabbage, 7 to rice, and 8 to corn. In addition, RNA-seq data downloaded from PGSC were utilized to reveal StPUBs' abiotic stress responses and tissue-specific expression in the doubled-monoploid potato (DM). Inaddition, we performed RNA-seq on the 'Atlantic' (drought-sensitive cultivar, DS) and the 'Qingshu NO.9' (drought-tolerant cultivar, DT) in early flowering, full-blooming, along with flower-falling stages to detect genes that might be involved in response to drought stress. Finally, quantitative real-time PCR (qPCR) was carried out to analyze three candidate genes for their expression levels within 100 mM NaCl- and 10% PEG 6000 (w/v)-treated potato plantlets for a 24-h period. Furthermore, we analyzed the drought tolerance of StPUB25 transgenic plants and found that overexpression of StPUB25 significantly increased peroxidase (POD) activity, reduced ROS (reactive oxygen species) and MDA (malondialdehyde) accumulation compared with wild-type (WT) plants, and enhancing drought tolerance of the transgenic plants. CONCLUSION In this study, three candidate genes related to drought tolerance in potato were excavated, and the function of StPUB25 under drought stress was verified. These results should provide valuable information to understand the potato StPUB gene family and investigate the molecular mechanisms of StPUBs regulating potato drought tolerance.
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Affiliation(s)
- Zhen Liu
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou, 730070, China
| | - Lei Wang
- Hebei North University, Zhangjiakou, 075000, China
| | - Yuanming Li
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, China
| | - Jinyong Zhu
- College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Zhitao Li
- College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Limin Chen
- College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Hongyang Li
- College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Tianbin Shi
- College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Panfeng Yao
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou, 730070, China
| | - Zhenzhen Bi
- College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Chao Sun
- College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Jiangping Bai
- College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Junlian Zhang
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, China
| | - Yuhui Liu
- State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou, 730070, China.
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Fan W, Liao X, Tan Y, Wang X, Schroeder JI, Li Z. Arabidopsis PLANT U-BOX44 down-regulates osmotic stress signaling by mediating Ca2+-DEPENDENT PROTEIN KINASE4 degradation. THE PLANT CELL 2023; 35:3870-3888. [PMID: 37338064 PMCID: PMC10533340 DOI: 10.1093/plcell/koad173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 04/20/2023] [Accepted: 06/19/2023] [Indexed: 06/21/2023]
Abstract
Calcium (Ca2+)-dependent protein kinases (CPKs) are essential regulators of plant responses to diverse environmental stressors, including osmotic stress. CPKs are activated by an increase in intracellular Ca2+ levels triggered by osmotic stress. However, how the levels of active CPK protein are dynamically and precisely regulated has yet to be determined. Here, we demonstrate that NaCl/mannitol-induced osmotic stress promoted the accumulation of CPK4 protein by disrupting its 26S proteasome-mediated CPK4 degradation in Arabidopsis (Arabidopsis thaliana). We isolated PLANT U-BOX44 (PUB44), a U-box type E3 ubiquitin ligase that ubiquitinates CPK4 and triggers its degradation. A calcium-free or kinase-inactive CPK4 variant was preferentially degraded compared to the Ca2+-bound active form of CPK4. Furthermore, PUB44 exhibited a CPK4-dependent negative role in the response of plants to osmotic stress. Osmotic stress induced the accumulation of CPK4 protein by inhibiting PUB44-mediated CPK4 degradation. The present findings reveal a mechanism for regulating CPK protein levels and establish the relevance of PUB44-dependent CPK4 regulation in modulating plant osmotic stress responses, providing insights into osmotic stress signal transduction mechanisms.
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Affiliation(s)
- Wei Fan
- Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Xiliang Liao
- Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Yanqiu Tan
- Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Xiruo Wang
- Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Julian I Schroeder
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Zixing Li
- Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
- Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
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Jiang L, Lin Y, Wang L, Peng Y, Yang M, Jiang Y, Hou G, Liu X, Li M, Zhang Y, Zhang Y, Chen Q, Wang Y, He W, Wang X, Tang H, Luo Y. Genome-wide identification and expression profiling reveal the regulatory role of U-box E3 ubiquitin ligase genes in strawberry fruit ripening and abiotic stresses resistance. FRONTIERS IN PLANT SCIENCE 2023; 14:1171056. [PMID: 37035055 PMCID: PMC10078948 DOI: 10.3389/fpls.2023.1171056] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 03/10/2023] [Indexed: 06/19/2023]
Abstract
The plant U-box (PUB) proteins are a type of E3 ubiquitin ligases well known for their functions in response to various stresses. They are also related to fruit development and ripening. However, PUB members possess such roles that remain unclear in strawberry. In this study, 155 PUB genes were identified in octoploid strawberry and classified into four groups. Their promoters possessed a variety of cis-acting elements, most of which are associated with abiotic stresses, followed by phytohormones response and development. Protein-protein interaction analysis suggested that FaU-box members could interact with each other as well as other proteins involved in hormone signaling and stress resistance. Transcriptome-based and RT-qPCR expression analysis revealed the potential involvement of FaU-box genes in resistance to stresses and fruit ripening. Of these, FaU-box98 and FaU-box136 were positively while FaU-box52 was negatively related to strawberry ripening. FaU-box98 comprehensively participated in resistance of ABA, cold, and salt, while FaU-box83 and FaU-box136 were broadly associated with drought and salt stresses. FaU-box18 and FaU-box52 were ABA-specific; FaU-box3 was specific to salt stress. In addition, the functional analysis of a randomly selected FaU-box (FaU-box127) showed that the transient overexpression of FaU-box127 promoted the ripening of strawberry fruit, along with significant changes in the expression levels of some ripening-related genes and the content of organic acid and soluble sugar. Overall, these findings provided comprehensive information about the FaU-box gene family and identified the potential FaU-box members participating in stress resistance and strawberry fruit ripening regulation.
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Affiliation(s)
- Leiyu Jiang
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Yuanxiu Lin
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
- Institute of Pomology & Olericulture, Sichuan Agricultural University, Chengdu, China
| | - Liangxin Wang
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Yuting Peng
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Min Yang
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Yuyan Jiang
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Guoyan Hou
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Xiaoyang Liu
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Mengyao Li
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Yunting Zhang
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
- Institute of Pomology & Olericulture, Sichuan Agricultural University, Chengdu, China
| | - Yong Zhang
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Qing Chen
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
| | - Yan Wang
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
- Institute of Pomology & Olericulture, Sichuan Agricultural University, Chengdu, China
| | - Wen He
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
- Institute of Pomology & Olericulture, Sichuan Agricultural University, Chengdu, China
| | - Xiaorong Wang
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
- Institute of Pomology & Olericulture, Sichuan Agricultural University, Chengdu, China
| | - Haoru Tang
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
- Institute of Pomology & Olericulture, Sichuan Agricultural University, Chengdu, China
| | - Ya Luo
- College of Horticulture, Sichuan Agricultural University, Chengdu, China
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Cui J, Ren G, Bai Y, Gao Y, Yang P, Chang J. Genome-wide identification and expression analysis of the U-box E3 ubiquitin ligase gene family related to salt tolerance in sorghum ( Sorghum bicolor L.). FRONTIERS IN PLANT SCIENCE 2023; 14:1141617. [PMID: 37008506 PMCID: PMC10063820 DOI: 10.3389/fpls.2023.1141617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/01/2023] [Indexed: 06/19/2023]
Abstract
Plant U-box (PUB) E3 ubiquitin ligases play essential roles in many biological processes and stress responses, but little is known about their functions in sorghum (Sorghum bicolor L.). In the present study, 59 SbPUB genes were identified in the sorghum genome. Based on the phylogenetic analysis, the 59 SbPUB genes were clustered into five groups, which were also supported by the conserved motifs and structures of these genes. SbPUB genes were found to be unevenly distributed on the 10 chromosomes of sorghum. Most PUB genes (16) were found on chromosome 4, but there were no PUB genes on chromosome 5. Analysis of cis-acting elements showed that SbPUB genes were involved in many important biological processes, particularly in response to salt stress. From proteomic and transcriptomic data, we found that several SbPUB genes had diverse expressions under different salt treatments. To verify the expression of SbPUBs, qRT-PCR analyses also were conducted under salt stress, and the result was consistent with the expression analysis. Furthermore, 12 SbPUB genes were found to contain MYB-related elements, which are important regulators of flavonoid biosynthesis. These results, which were consistent with our previous multi-omics analysis of sorghum salt stress, laid a solid foundation for further mechanistic study of salt tolerance in sorghum. Our study showed that PUB genes play a crucial role in regulating salt stress, and might serve as promising targets for the breeding of salt-tolerant sorghum in the future.
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Affiliation(s)
- Jianghui Cui
- College of Agronomy, Hebei Agricultural University, Baoding, China
- North China Key Laboratory for Germplasm Resources of Education Ministry, Baoding, China
| | - Genzeng Ren
- College of Agronomy, Hebei Agricultural University, Baoding, China
- North China Key Laboratory for Germplasm Resources of Education Ministry, Baoding, China
| | - Yuzhe Bai
- College of Agronomy, Hebei Agricultural University, Baoding, China
- North China Key Laboratory for Germplasm Resources of Education Ministry, Baoding, China
| | - Yukun Gao
- College of Agronomy, Hebei Agricultural University, Baoding, China
- North China Key Laboratory for Germplasm Resources of Education Ministry, Baoding, China
| | - Puyuan Yang
- College of Agronomy, Hebei Agricultural University, Baoding, China
- North China Key Laboratory for Germplasm Resources of Education Ministry, Baoding, China
| | - Jinhua Chang
- College of Agronomy, Hebei Agricultural University, Baoding, China
- North China Key Laboratory for Germplasm Resources of Education Ministry, Baoding, China
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Sirko A, Wawrzyńska A, Brzywczy J, Sieńko M. Control of ABA Signaling and Crosstalk with Other Hormones by the Selective Degradation of Pathway Components. Int J Mol Sci 2021; 22:4638. [PMID: 33924944 PMCID: PMC8125534 DOI: 10.3390/ijms22094638] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 04/25/2021] [Accepted: 04/26/2021] [Indexed: 12/13/2022] Open
Abstract
A rapid and appropriate genetic and metabolic acclimation, which is crucial for plants' survival in a changing environment, is maintained due to the coordinated action of plant hormones and cellular degradation mechanisms influencing proteostasis. The plant hormone abscisic acid (ABA) rapidly accumulates in plants in response to environmental stress and plays a pivotal role in the reaction to various stimuli. Increasing evidence demonstrates a significant role of autophagy in controlling ABA signaling. This field has been extensively investigated and new discoveries are constantly being provided. We present updated information on the components of the ABA signaling pathway, particularly on transcription factors modified by different E3 ligases. Then, we focus on the role of selective autophagy in ABA pathway control and review novel evidence on the involvement of autophagy in different parts of the ABA signaling pathway that are important for crosstalk with other hormones, particularly cytokinins and brassinosteroids.
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Affiliation(s)
- Agnieszka Sirko
- Laboratory of Plant Protein Homeostasis, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, ul. Pawinskiego 5A, 02-106 Warsaw, Poland; (J.B.); (M.S.)
| | - Anna Wawrzyńska
- Laboratory of Plant Protein Homeostasis, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, ul. Pawinskiego 5A, 02-106 Warsaw, Poland; (J.B.); (M.S.)
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7
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Yu Y, Meng X, Guo D, Yang S, Zhang G, Liang Z. Grapevine U-Box E3 Ubiquitin Ligase VlPUB38 Negatively Regulates Fruit Ripening by Facilitating Abscisic-Aldehyde Oxidase Degradation. PLANT & CELL PHYSIOLOGY 2021; 61:2043-2054. [PMID: 32976591 DOI: 10.1093/pcp/pcaa118] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
The plant U-box E3 ubiquitin ligase-mediated ubiquitin/26S proteasome degradation system plays a key role in plant growth and development. Previously identified as a member of the grape PUB gene family, PUB38 was shown to participate in the berry-ripening progress. Here, we demonstrate that the E3 ligase VlPUB38 mediates abscisic acid (ABA) synthesis via 26S proteasome degradation and its involvement in regulating fruit-ripening processes. Strawberry-overexpressing VlPUB38 lines displayed obvious inhibition of mature phenotype, and this was rescued by exogenous ABA treatment and MG132. Post-ABA treatment, expression levels of ABA response-related genes in VlPUB38-overexpressed Arabidopsis significantly exceeded controls. Strawberry and Arabidopsis ectopic expression assays suggest that VlPUB38 negatively regulates fruit ripening in an ABA-dependent manner. Moreover, VlPUB38 has ubiquitin ligase activity, which depends on the U-box-conserved domain. VlPUB38 interacts with abscisic-aldehyde oxidase (VlAAO), targeting VlAAO proteolysis via the 26S proteasome system. These results indicate that VlPUB38 negatively regulates grape fruit ripening by mediating the degradation of key factor VlAAO in the ABA synthesis pathway.
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Affiliation(s)
- Yihe Yu
- College of Forestry, Henan University of Science and Technology, Luoyang, Henan 471000, China
- Henan Engineering Technology Research Center of Quality Regulation and Controlling of Horticultural Plants, Luoyang, Henan 471000, China
| | - Xiangxuan Meng
- College of Forestry, Henan University of Science and Technology, Luoyang, Henan 471000, China
- Henan Engineering Technology Research Center of Quality Regulation and Controlling of Horticultural Plants, Luoyang, Henan 471000, China
| | - Dalong Guo
- College of Forestry, Henan University of Science and Technology, Luoyang, Henan 471000, China
- Henan Engineering Technology Research Center of Quality Regulation and Controlling of Horticultural Plants, Luoyang, Henan 471000, China
| | - Shengdi Yang
- College of Forestry, Henan University of Science and Technology, Luoyang, Henan 471000, China
- Henan Engineering Technology Research Center of Quality Regulation and Controlling of Horticultural Plants, Luoyang, Henan 471000, China
| | - Guohai Zhang
- College of Forestry, Henan University of Science and Technology, Luoyang, Henan 471000, China
- Henan Engineering Technology Research Center of Quality Regulation and Controlling of Horticultural Plants, Luoyang, Henan 471000, China
| | - Zhenchang Liang
- Beijing Key Laboratory of Grape Science and Enology and CAS Key Laboratory of Plant Resource, Institute of Botany, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100093, China
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8
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Li Q, Li B, Wang J, Chang X, Mao X, Jing R. TaPUB15
, a U‐Box E3 ubiquitin ligase gene from wheat, enhances salt tolerance in rice. Food Energy Secur 2020. [DOI: 10.1002/fes3.250] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Qiaoru Li
- National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing China
| | - Bo Li
- National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing China
| | - Jingyi Wang
- National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing China
| | - Xiaoping Chang
- National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing China
| | - Xinguo Mao
- National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing China
| | - Ruilian Jing
- National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing China
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Wang N, Liu Y, Cai Y, Tang J, Li Y, Gai J. The soybean U-box gene GmPUB6 regulates drought tolerance in Arabidopsis thaliana. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 155:284-296. [PMID: 32795910 DOI: 10.1016/j.plaphy.2020.07.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 06/15/2020] [Accepted: 07/10/2020] [Indexed: 06/11/2023]
Abstract
The plant U-box (PUB) proteins function as E3 ligases to poly-ubiquitinate the target proteins for their degradation or post-translational modification. PUBs also play important roles in regulation of diverse biological processes, including plant response to environmental stresses. In this study, the functional characterization of a soybean PUB gene, GmPUB6, was performed. GmPUB6 was mainly localized to peroxisome, and showed E3 ubiquitin ligase activity. The transcript levels of GmPUB6 in soybean leaves and roots were induced by abscisic acid (ABA), high salinity and polyethylene glycol (PEG) treatment. Comparing with the wild-type (WT) plants, overexpression of GmPUB6 in Arabidopsis thaliana decreased plant survival rate after drought stress, reduced seed germination rate and root elongation under mannitol (osmotic) stress, and suppressed ABA- or mannitol-mediated stomatal closure. In addition, under dehydration stress, the relative expression levels of seven stress responsive genes, including ABI1, DREB2A, KIN2, RAB18, RD20, RD29A and RD29B, were lower in GmPUB6-overexpressed plants than WT. Taken together, these results suggest that GmPUB6 functions as a negative regulator in drought tolerance, and plays an important role in osmotic stress and ABA signaling pathways, which might be the possible mechanism of PUB6 participating in drought stress response.
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Affiliation(s)
- Ning Wang
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, National Center for Soybean Improvement, Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture), Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing, 210095, China; Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing, 210014, China
| | - Yandang Liu
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, National Center for Soybean Improvement, Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture), Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yuanyuan Cai
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, National Center for Soybean Improvement, Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture), Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jiajun Tang
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, National Center for Soybean Improvement, Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture), Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yan Li
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, National Center for Soybean Improvement, Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture), Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing, 210095, China.
| | - Junyi Gai
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, National Center for Soybean Improvement, Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture), Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing, 210095, China.
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10
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So WM, Kim SY, Hyoung S, Shin JS. The novel protein CSAP accelerates leaf senescence and is negatively regulated by SAUL1 in the dark. PLANT CELL REPORTS 2020; 39:325-334. [PMID: 31773253 DOI: 10.1007/s00299-019-02493-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 11/18/2019] [Indexed: 05/25/2023]
Abstract
The chloroplast-localized protein CSAP is an ABA-responsive factor and positively regulates dark-induced senescence. This phenomenon is controlled by SAUL1 in Arabidopsis. We report here that CSAP (Chloroplast-localized Senescence-Associated Protein, AT5G39520) functions as a positive regulator of senescence and is controlled by SAUL1 (Senescence Associated E3 Ubiquitin Ligase 1) in Arabidopsis. CSAP transcript level was gradually increased when senescence was progressed. Under dark conditions, the csap mutant showed delayed leaf senescence and reduced chlorophyll breakdown, but overexpression of CSAP accelerated leaf senescence and expressions of chlorophyll catabolic genes were up-regulated compared to the wild-type (WT). NCED3 and AAO3, which are involved in ABA biosynthesis, also showed higher expression in the overexpression lines than the WT. It is known that the CSAP transcript is increased in the saul1 mutant that shows precocious senescence. In our experiments, we confirmed that CSAP interacts with SAUL1 by the yeast two-hybrid and pull-down assays. In addition, we found that SAUL1 decreases the stability of CSAP in the presence of ABA. Taken together, we suggest that CSAP accelerates leaf senescence in the dark and this process is controlled by SAUL1.
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Affiliation(s)
- Won Mi So
- Division of Life Sciences, Korea University, Seoul, 02841, Korea
| | - Soo Youn Kim
- Division of Life Sciences, Korea University, Seoul, 02841, Korea
- Cloning Department, Bionics, Seoul, 04778, Korea
| | - Sujin Hyoung
- Division of Life Sciences, Korea University, Seoul, 02841, Korea
| | - Jeong Sheop Shin
- Division of Life Sciences, Korea University, Seoul, 02841, Korea.
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11
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Wang J, Liu S, Liu H, Chen K, Zhang P. PnSAG1, an E3 ubiquitin ligase of the Antarctic moss Pohlia nutans, enhanced sensitivity to salt stress and ABA. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 141:343-352. [PMID: 31207495 DOI: 10.1016/j.plaphy.2019.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/03/2019] [Accepted: 06/03/2019] [Indexed: 06/09/2023]
Abstract
Plant U-box (PUB) E3 ubiquitin ligases play crucial roles in the plant response to abiotic stress and the phytohormone abscisic acid (ABA) signaling, but little is known about them in bryophytes. Here, a representative U-box armadillo repeat (PUB-ARM) ubiquitin E3 ligase from Antarctic moss Pohlia nutans (PnSAG1), was explored for its role in abiotic stress response in Arabidopsis thaliana and Physcomitrella patens. The expression of PnSAG1 was rapidly induced by exogenous abscisic acid (ABA), salt, cold and drought stresses. PnSAG1 was localized to the cytoplasm and showed E3 ubiquitin ligase activity by in vitro ubiquitination assay. The PnSAG1-overexpressing Arabidopsis enhanced the sensitivity with respect to ABA and salt stress during seed germination and early root growth. Similarly, heterogeneous overexpression of PnSAG1 in P. patens was more sensitive to the salinity and ABA in their gametophyte growth. The analysis by RT-qPCR revealed that the expression of salt stress/ABA-related genes were downregulated in PnSAG1-overexpressing plants after salt treatment. Taken together, our results indicated that PnSAG1 plays a negative role in plant response to ABA and salt stress.
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Affiliation(s)
- Jing Wang
- National Glycoengineering Research Center and School of Life Science, Shandong University, Qingdao, 266237, China; Key Laboratory of Pediatrics, Liaocheng People's Hospital, Liaocheng, Shandong, 252000, China
| | - Shenghao Liu
- Marine Ecology Research Center, The First Institute of Oceanography, State Oceanic Administration, Qingdao, 266061, China
| | - Hongwei Liu
- National Glycoengineering Research Center and School of Life Science, Shandong University, Qingdao, 266237, China
| | - Kaoshan Chen
- National Glycoengineering Research Center and School of Life Science, Shandong University, Qingdao, 266237, China
| | - Pengying Zhang
- National Glycoengineering Research Center and School of Life Science, Shandong University, Qingdao, 266237, China.
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12
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Classification of barley U-box E3 ligases and their expression patterns in response to drought and pathogen stresses. BMC Genomics 2019; 20:326. [PMID: 31035917 PMCID: PMC6489225 DOI: 10.1186/s12864-019-5696-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 04/15/2019] [Indexed: 12/20/2022] Open
Abstract
Background Controlled turnover of proteins as mediated by the ubiquitin proteasome system (UPS) is an important element in plant defense against environmental and pathogen stresses. E3 ligases play a central role in subjecting proteins to hydrolysis by the UPS. Recently, it has been demonstrated that a specific class of E3 ligases termed the U-box ligases are directly associated with the defense mechanisms against abiotic and biotic stresses in several plants. However, no studies on U-box E3 ligases have been performed in one of the important staple crops, barley. Results In this study, we identified 67 putative U-box E3 ligases from the barley genome and expressed sequence tags (ESTs). Similar to Arabidopsis and rice U-box E3 ligases, most of barley U-box E3 ligases possess evolutionary well-conserved domain organizations. Based on the domain compositions and arrangements, the barley U-box proteins were classified into eight different classes. Along with this new classification, we refined the previously reported classifications of U-box E3 ligase genes in Arabidopsis and rice. Furthermore, we investigated the expression profile of 67 U-box E3 ligase genes in response to drought stress and pathogen infection. We observed that many U-box E3 ligase genes were specifically up-and-down regulated by drought stress or by fungal infection, implying their possible roles of some U-box E3 ligase genes in the stress responses. Conclusion This study reports the classification of U-box E3 ligases in barley and their expression profiles against drought stress and pathogen infection. Therefore, the classification and expression profiling of barley U-box genes can be used as a platform to functionally define the stress-related E3 ligases in barley. Electronic supplementary material The online version of this article (10.1186/s12864-019-5696-z) contains supplementary material, which is available to authorized users.
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13
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Regulation of Plant Immunity by the Proteasome. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2019; 343:37-63. [DOI: 10.1016/bs.ircmb.2018.06.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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14
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Adler G, Mishra AK, Maymon T, Raveh D, Bar-Zvi D. Overexpression of Arabidopsis ubiquitin ligase AtPUB46 enhances tolerance to drought and oxidative stress. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 276:220-228. [PMID: 30348322 DOI: 10.1016/j.plantsci.2018.08.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 08/22/2018] [Accepted: 08/27/2018] [Indexed: 06/08/2023]
Abstract
The U-Box E3 ubiquitin ligase, AtPUB46, functions in the drought response: T-DNA insertion mutants of this single paralogous gene are hypersensitive to water- and oxidative stress (Adler et al. BMC Plant Biology 17:8, 2017). Here we analyze the phenotype of AtPUB46 overexpressing (OE) plants. AtPUB46-OE show increased tolerance to water stress and have smaller leaf blades and reduced stomatal pore area and stomatal index compared with wild type (WT). Despite this, the rate of water loss from detached rosettes is similar in AtPUB46-OE and WT plants. Germination of AtPUB46-OE seeds was less sensitive to salt than WT whereas seedling greening was more sensitive. We observed a complex response to oxidative stress applied by different agents: AtPUB46-OE plants were hypersensitive to H2O2 but hyposensitive to methyl viologen. AtPUB46-GFP fusion protein is cytoplasmic, however, in response to H2O2 a considerable proportion translocates to the nucleus. We conclude that the differential stress phenotype of the AtPUB46-OE does not result from its smaller leaf size but from a change in the activity of a stress pathway(s) regulated by a degradation substrate of the AtPUB46 E3 and also from a reduction in stomatal pore size and index.
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Affiliation(s)
- Guy Adler
- Department of Life Sciences, Ben-Gurion University of the Negev, 1 Ben-Gurion Blvd, Beer-Sheva 8410501, Israel; The Doris and Bertie I. Black Center for Bioenergetics in Life Sciences, Ben-Gurion University of the Negev, 1 Ben-Gurion Blvd, Beer-Sheva 8410501, Israel
| | - Amit Kumar Mishra
- Department of Life Sciences, Ben-Gurion University of the Negev, 1 Ben-Gurion Blvd, Beer-Sheva 8410501, Israel; The Doris and Bertie I. Black Center for Bioenergetics in Life Sciences, Ben-Gurion University of the Negev, 1 Ben-Gurion Blvd, Beer-Sheva 8410501, Israel
| | - Tzofia Maymon
- Department of Life Sciences, Ben-Gurion University of the Negev, 1 Ben-Gurion Blvd, Beer-Sheva 8410501, Israel; The Doris and Bertie I. Black Center for Bioenergetics in Life Sciences, Ben-Gurion University of the Negev, 1 Ben-Gurion Blvd, Beer-Sheva 8410501, Israel
| | - Dina Raveh
- Department of Life Sciences, Ben-Gurion University of the Negev, 1 Ben-Gurion Blvd, Beer-Sheva 8410501, Israel
| | - Dudy Bar-Zvi
- Department of Life Sciences, Ben-Gurion University of the Negev, 1 Ben-Gurion Blvd, Beer-Sheva 8410501, Israel; The Doris and Bertie I. Black Center for Bioenergetics in Life Sciences, Ben-Gurion University of the Negev, 1 Ben-Gurion Blvd, Beer-Sheva 8410501, Israel.
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15
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Lim CW, Baek W, Lee SC. Roles of pepper bZIP protein CaDILZ1 and its interacting partner RING-type E3 ligase CaDSR1 in modulation of drought tolerance. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 96:452-467. [PMID: 30051516 DOI: 10.1111/tpj.14046] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 07/05/2018] [Accepted: 07/11/2018] [Indexed: 05/20/2023]
Abstract
Abscisic acid (ABA) is a plant hormone that plays a key role in the environmental stress response, especially the induction of ABA-responsive and stress-responsive genes and modulation of the stomatal aperture in response to drought stress. Here, we identified CaDILZ1 (Capsicum annuum Drought-Induced Leucine Zipper 1) belonging to subgroup D of the bZIP protein family; gene functions of this family in response to ABA and drought signaling still remain unknown. CaDILZ1 expression was significantly induced in pepper leaves after exposure to ABA, drought, and NaCl. The CaDILZ1 protein localized in the nucleus of plant cells. In response to drought stress, CaDILZ1-silenced pepper and CaDILZ1-overexpressing Arabidopsis plants exhibited drought-sensitive and drought-tolerant phenotypes, respectively, via altered ABA content, stomatal closure, and expression of ABA-responsive and drought-responsive marker genes. We isolated the RING finger protein CaDSR1 (Capsicum annuum Drought Sensitive RING finger protein 1), which interacted with CaDILZ1 in the nucleus. The CaDSR1 protein exhibited E3 ligase activity and promoted CaDILZ1 degradation via the 26S proteasome pathway. Under drought stress conditions, CaDSR1-silenced pepper and CaDSR1-overexpressing Arabidopsis plants exhibited contrasting phenotypes to those of CaDILZ1-silenced pepper and CaDILZ1-overexpressing Arabidopsis plants. Taken together, our data suggest that CaDSR1 and CaDILZ1 function in ABA-mediated drought stress signaling in pepper plants.
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Affiliation(s)
- Chae Woo Lim
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, 06974, Korea
| | - Woonhee Baek
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, 06974, Korea
| | - Sung Chul Lee
- Department of Life Science (BK21 program), Chung-Ang University, Seoul, 06974, Korea
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Role of the Ubiquitin Proteasome System in Plant Response to Abiotic Stress. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 343:65-110. [PMID: 30712675 DOI: 10.1016/bs.ircmb.2018.05.012] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ubiquitination is a prevalent post-translation modification system that is involved in almost all aspects of eukaryotic biology. It involves the attachment of ubiquitin, a small, highly conserved protein to selected substrates. The most notable function of ubiquitin is the targeting of modified proteins to the multi-proteolytic 26S proteasome complex for degradation. The ubiquitin proteasome system (UPS) regulates the abundance of numerous enzymes, structural and regulatory proteins ensuring proper cellular function. Plants utilize the UPS to facilitate cellular changes required to respond to and tolerate adverse growth conditions. In this review, the regulatory role of the UPS in responses to abiotic stress is discussed, particularly the function of ubiquitin-dependent degradation in the suppression, activation and attenuation or termination of stress signaling.
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17
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Trujillo M. News from the PUB: plant U-box type E3 ubiquitin ligases. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:371-384. [PMID: 29237060 DOI: 10.1093/jxb/erx411] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/25/2017] [Indexed: 05/05/2023]
Abstract
Plant U-box type E3 ubiquitin ligases (PUBs) are well known for their functions in a variety of stress responses, including immune responses and the adaptation to abiotic stresses. First linked to pollen self-incompatibility, their repertoire of roles has grown to encompass also the regulation of developmental processes. Notably, new studies provide clues to their mode of action, underline the existence of conserved PUB-kinase modules, and suggest new links to G-protein signalling, placing PUBs at the crossroads of major signalling hubs. The frequent association with membranes, by interacting and/or targeting membrane proteins, as well as through a recently reported direct interaction with phospholipids, indicates a general function in the control of vesicle transport and their cargoes. This review aims to give an overview of the most significant advances in the field, while also trying to identify common themes of PUB function.
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Affiliation(s)
- Marco Trujillo
- Independent Junior Research Group-Ubiquitination in Immunity, Leibniz Institute of Plant Biochemistry, Germany
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18
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Seo DH, Ahn MY, Park KY, Kim EY, Kim WT. The N-Terminal UND Motif of the Arabidopsis U-Box E3 Ligase PUB18 Is Critical for the Negative Regulation of ABA-Mediated Stomatal Movement and Determines Its Ubiquitination Specificity for Exocyst Subunit Exo70B1. THE PLANT CELL 2016; 28:2952-2973. [PMID: 27956469 PMCID: PMC5240735 DOI: 10.1105/tpc.16.00347] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 11/18/2016] [Accepted: 12/09/2016] [Indexed: 05/20/2023]
Abstract
The Arabidopsis thaliana U-box E3 ligases PUB18/PUB19 and PUB22/PUB23 are negative regulators of drought stress responses. PUB18/PUB19 regulate the drought stress response in an abscisic acid (ABA)-dependent manner, whereas PUB22/PUB23 regulate this response in an ABA-independent manner. A major structural difference between PUB18/PUB19 and PUB22/PUB23 is the presence of the UND (U-box N-terminal domain). Here, we focused on elucidating the molecular mechanism that mediates the functional difference between PUB18 and PUB22 and found that the UNDPUB18 was critically involved in the negative regulation of ABA-mediated stomatal movements. Exo70B1, a subunit of the exocyst complex, was identified as a target of PUB18, whereas Exo70B2 was a substrate of PUB22. However, the ∆UND-PUB18 derivative failed to ubiquitinate Exo70B1, but ubiquitinated Exo70B2. By contrast, the UNDPUB18-PUB22 chimeric protein ubiquitinated Exo70B1 instead of Exo70B2, suggesting that the ubiquitination specificities of PUB18 and PUB22 to Exo70B1 and Exo70B2, respectively, are dependent on the presence or absence of the UNDPUB18 motif. The ABA-insensitive phenotypes of the pub18 pub19 exo70b1 triple mutant were reminiscent of those of exo70b1 rather than pub18 pub19, indicating that Exo70B1 functions downstream of PUB18. Overall, our results suggest that the UNDPUB18 motif is crucial for the negative regulation of ABA-dependent stomatal movement and for determination of its ubiquitination specificity to Exo70B1.
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Affiliation(s)
- Dong Hye Seo
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Min Yong Ahn
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Ki Youl Park
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Eun Yu Kim
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Woo Taek Kim
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
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19
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Lee IH, Lee IC, Kim J, Kim JH, Chung EH, Kim HJ, Park SJ, Kim YM, Kang SK, Nam HG, Woo HR, Lim PO. NORE1/SAUL1 integrates temperature-dependent defense programs involving SGT1b and PAD4 pathways and leaf senescence in Arabidopsis. PHYSIOLOGIA PLANTARUM 2016; 158:180-99. [PMID: 26910207 DOI: 10.1111/ppl.12434] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 12/16/2015] [Accepted: 01/06/2016] [Indexed: 05/06/2023]
Abstract
Leaf senescence is not only primarily governed by developmental age but also influenced by various internal and external factors. Although some genes that control leaf senescence have been identified, the detailed regulatory mechanisms underlying integration of diverse senescence-associated signals into the senescence programs remain to be elucidated. To dissect the regulatory pathways involved in leaf senescence, we isolated the not oresara1-1 (nore1-1) mutant showing accelerated leaf senescence phenotypes from an EMS-mutagenized Arabidopsis thaliana population. We found that altered transcriptional programs in defense response-related processes were associated with the accelerated leaf senescence phenotypes observed in nore1-1 through microarray analysis. The nore1-1 mutation activated defense program, leading to enhanced disease resistance. Intriguingly, high ambient temperature effectively suppresses the early senescence and death phenotypes of nore1-1. The gene responsible for the phenotypes of nore1-1 contains a missense mutation in SENESCENCE-ASSOCIATED E3 UBIQUITIN LIGASE 1 (SAUL1), which was reported as a negative regulator of premature senescence in the light intensity- and PHYTOALEXIN DEFICIENT 4 (PAD4)-dependent manner. Through extensive double mutant analyses, we recently identified suppressor of the G2 Allele of SKP1b (SGT1b), one of the positive regulators for disease resistance conferred by many resistance (R) proteins, as a downstream signaling component in NORE1-mediated senescence and cell death pathways. In conclusion, NORE1/SAUL1 is a key factor integrating signals from temperature-dependent defense programs and leaf senescence in Arabidopsis. These findings provide a new insight that plants might utilize defense response program in regulating leaf senescence process, possibly through recruiting the related genes during the evolution of the leaf senescence program.
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Affiliation(s)
- Il Hwan Lee
- Department of Life Sciences, POSTECH, Pohang, 37673, Republic of Korea
| | - In Chul Lee
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Republic of Korea
| | - Jeongsik Kim
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Republic of Korea
| | - Jin Hee Kim
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Republic of Korea
| | - Eui-Hwan Chung
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Hyo Jung Kim
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Republic of Korea
| | - Su Jin Park
- School of Interdisciplinary Bioscience and Bioengineering, POSTECH, Pohang, 37673, Republic of Korea
| | - Yong Min Kim
- Department of Bioscience, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Sin Kyu Kang
- Department of Bioscience, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Hong Gil Nam
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Republic of Korea.
- Department of New Biology, DGIST, Daegu, 42988, Republic of Korea.
| | - Hye Ryun Woo
- Department of New Biology, DGIST, Daegu, 42988, Republic of Korea.
| | - Pyung Ok Lim
- Department of New Biology, DGIST, Daegu, 42988, Republic of Korea.
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20
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Wang N, Liu Y, Cong Y, Wang T, Zhong X, Yang S, Li Y, Gai J. Genome-Wide Identification of Soybean U-Box E3 Ubiquitin Ligases and Roles of GmPUB8 in Negative Regulation of Drought Stress Response in Arabidopsis. PLANT & CELL PHYSIOLOGY 2016; 57:1189-209. [PMID: 27057003 DOI: 10.1093/pcp/pcw068] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Accepted: 03/13/2016] [Indexed: 05/05/2023]
Abstract
Plant U-box (PUB) E3 ubiquitin ligases play important roles in hormone signaling pathways and response to abiotic stresses, but little is known about them in soybean, Glycine max. Here, we identified and characterized 125 PUB genes from the soybean genome, which were classified into eight groups according to their protein domains. Soybean PUB genes (GmPUB genes) are broadly expressed in many tissues and are a little more abundant in the roots than in the other tissues. Nine GmPUB genes, GmPUB1-GmPUB9, showed induced expression patterns by drought, and the expression of GmPUB8 was also induced by exogenous ABA and NaCl. GmPUB8 was localized to post-Golgi compartments, interacting with GmE2 protein as demonstrated by yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) experiments, and showed E3 ubiquitin ligase activity by in vitro ubiquitination assay. Heterogeneous overexpression of GmPUB8 in Arabidopsis showed decreased drought tolerance, enhanced sensitivity with respect to osmotic and salt stress inhibition of seed germination and seedling growth, and inhibited ABA- and mannitol-mediated stomatal closure. Eight drought stress-related genes were less induced in GmPUB8-overexpressing Arabidopsis after drought treatment compared with the wild type and the pub23 mutant. Taken together, our results suggested that GmPUB8 might negatively regulate plant response to drought stress. In addition, Y2H and BiFC showed that GmPUB8 interacted with soybean COL (CONSTANS LIKE) protein. GmPUB8-overexpressing Arabidopsis flowered earlier under middle- and short-day conditions but later under long-day conditions, indicating that GmPUB8 might regulate flowering time in the photoperiod pathway. This study helps us to understand the functions of PUB E3 ubiquitin ligases in soybean.
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Affiliation(s)
- Ning Wang
- National Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement/Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture)/Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China
| | - Yaping Liu
- National Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement/Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture)/Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China
| | - Yahui Cong
- National Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement/Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture)/Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China
| | - Tingting Wang
- National Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement/Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture)/Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiujuan Zhong
- National Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement/Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture)/Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China
| | - Shouping Yang
- National Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement/Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture)/Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China
| | - Yan Li
- National Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement/Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture)/Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China
| | - Junyi Gai
- National Key Laboratory of Crop Genetics and Germplasm Enhancement/National Center for Soybean Improvement/Key Laboratory for Biology and Genetic Improvement of Soybean (General, Ministry of Agriculture)/Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China
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21
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Disch EM, Tong M, Kotur T, Koch G, Wolf CA, Li X, Hoth S. Membrane-Associated Ubiquitin Ligase SAUL1 Suppresses Temperature- and Humidity-Dependent Autoimmunity in Arabidopsis. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2016; 29:69-80. [PMID: 26505534 DOI: 10.1094/mpmi-07-15-0146-r] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Plants have evolved elaborate mechanisms to regulate pathogen defense. Imbalances in this regulation may result in autoimmune responses that are affecting plant growth and development. In Arabidopsis, SAUL1 encodes a plant U-box ubiquitin ligase and regulates senescence and cell death. Here, we show that saul1-1 plants exhibit characteristics of an autoimmune mutant. A decrease in relative humidity or temperature resulted in reduced growth and systemic lesioning of saul1-1 rosettes. These physiological changes are associated with increased expression of salicylic acid-dependent and pathogenesis-related (PR) genes. Consistently, resistance of saul1-1 plants against Pseudomonas syringae pv. maculicola ES4326, P. syringae pv. tomato DC3000, or Hyaloperonospora arabidopsidis Noco2 was enhanced. Transmission electron microscopy revealed alterations in saul1-1 chloroplast ultrastructure and cell-wall depositions. Confocal analysis on aniline blue-stained leaf sections and cellular universal micro spectrophotometry further showed that these cell-wall depositions contain callose and lignin. To analyze signaling downstream of SAUL1, we performed epistasis analyses between saul1-1 and mutants in the EDS1/PAD4/SAG101 hub. All phenotypes observed in saul1-1 plants at low temperature were dependent on EDS1 and PAD4 but not SAG101. Taken together, SAUL1 negatively regulates immunity upstream of EDS1/PAD4, likely through the degradation of an unknown activator of the pathway.
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Affiliation(s)
- Eva-Maria Disch
- 1 Molekulare Pflanzenphysiologie, Biozentrum Klein Flottbek, Universität Hamburg, Hamburg, Germany
| | - Meixuezi Tong
- 2 Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Tanja Kotur
- 1 Molekulare Pflanzenphysiologie, Biozentrum Klein Flottbek, Universität Hamburg, Hamburg, Germany
| | - Gerald Koch
- 3 Thünen-Institute of Wood Technology and Wood Biology, Hamburg, Germany
| | - Carl-Asmus Wolf
- 1 Molekulare Pflanzenphysiologie, Biozentrum Klein Flottbek, Universität Hamburg, Hamburg, Germany
| | - Xin Li
- 2 Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Stefan Hoth
- 1 Molekulare Pflanzenphysiologie, Biozentrum Klein Flottbek, Universität Hamburg, Hamburg, Germany
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Yang L, Liu Q, Liu Z, Yang H, Wang J, Li X, Yang Y. Arabidopsis C3HC4-RING finger E3 ubiquitin ligase AtAIRP4 positively regulates stress-responsive abscisic acid signaling. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2016; 58:67-80. [PMID: 25913143 DOI: 10.1111/jipb.12364] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 04/23/2015] [Indexed: 05/20/2023]
Abstract
Degradation of proteins via the ubiquitin system is an important step in many stress signaling pathways in plants. E3 ligases recognize ligand proteins and dictate the high specificity of protein degradation, and thus, play a pivotal role in ubiquitination. Here, we identified a gene, named Arabidopsis thaliana abscisic acid (ABA)-insensitive RING protein 4 (AtAIRP4), which is induced by ABA and other stress treatments. AtAIRP4 encodes a cellular protein with a C3HC4-RING finger domain in its C-terminal side, which has in vitro E3 ligase activity. Loss of AtAIRP4 leads to a decrease in sensitivity of root elongation and stomatal closure to ABA, whereas overexpression of this gene in the T-DNA insertion mutant atairp4 effectively recovered the ABA-associated phenotypes. AtAIRP4 overexpression plants were hypersensitive to salt and osmotic stresses during seed germination, and showed drought avoidance compared with the wild-type and atairp4 mutant plants. In addition, the expression levels of ABA- and drought-induced marker genes in AtAIRP4 overexpression plants were markedly higher than those in the wild-type and atairp4 mutant plants. Hence, these results indicate that AtAIRP4 may act as a positive regulator of ABA-mediated drought avoidance and a negative regulator of salt tolerance in Arabidopsis.
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Affiliation(s)
- Liang Yang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, China
- The Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610066, China
| | - Qiaohong Liu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, China
| | - Zhibin Liu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, China
| | - Hao Yang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, China
| | - Jianmei Wang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, China
| | - Xufeng Li
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, China
| | - Yi Yang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, China
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Sharma B, Joshi D, Yadav PK, Gupta AK, Bhatt TK. Role of Ubiquitin-Mediated Degradation System in Plant Biology. FRONTIERS IN PLANT SCIENCE 2016; 7:806. [PMID: 27375660 PMCID: PMC4897311 DOI: 10.3389/fpls.2016.00806] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 05/23/2016] [Indexed: 05/05/2023]
Abstract
Ubiquitin-mediated proteasomal degradation is an important mechanism to control protein load in the cells. Ubiquitin binds to a protein on lysine residue and usually promotes its degradation through 26S proteasome system. Abnormal proteins and regulators of many processes, are targeted for degradation by the ubiquitin-proteasome system. It allows cells to maintain the response to cellular level signals and altered environmental conditions. The ubiquitin-mediated proteasomal degradation system plays a key role in the plant biology, including abiotic stress, immunity, and hormonal signaling by interfering with key components of these pathways. The involvement of the ubiquitin system in many vital processes led scientists to explore more about the ubiquitin machinery and most importantly its targets. In this review, we have summarized recent discoveries of the plant ubiquitin system and its involvement in critical processes of plant biology.
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Cho SK, Bae H, Ryu MY, Wook Yang S, Kim WT. PUB22 and PUB23 U-BOX E3 ligases directly ubiquitinate RPN6, a 26S proteasome lid subunit, for subsequent degradation in Arabidopsis thaliana. Biochem Biophys Res Commun 2015; 464:994-999. [PMID: 26188517 DOI: 10.1016/j.bbrc.2015.07.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 07/06/2015] [Indexed: 11/17/2022]
Abstract
Drought stress strongly affects plant growth and development, directly connected with crop yields, accordingly. However, related to the function of U-BOX E3 ligases, the underlying molecular mechanisms of desiccation stress response in plants are still largely unknown. Here we report that PUB22 and PUB23, two U-box E3 ligase homologs, tether ubiquitins to 19S proteasome regulatory particle (RP) subunit RPN6, leading to its degradation. RPN6 was identified as an interacting substrate of PUB22 by yeast two-hybrid screening, and in vitro pull-down assay confirmed that RPN6 interacts not only with PUB22, but also with PUB23. Both PUB22 and PUB23 were able to conjugate ubiquitins on RPN6 in vitro. Furthermore, RPN6 showed a shorter protein half-life in PUB22 overexpressing plants than in wild-type, besides RPN6 was significantly stabilized in pub22pub23 double knockout plants. Taken together, these results solidify a notion that PUB22 and PUB23 can alter the activity of 26S proteasome in response to drought stress.
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Affiliation(s)
- Seok Keun Cho
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Hansol Bae
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Moon Young Ryu
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Seong Wook Yang
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark.
| | - Woo TaeK Kim
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, South Korea.
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Genome-wide survey and expression analysis of the PUB family in Chinese cabbage (Brassica rapa ssp. pekinesis). Mol Genet Genomics 2015; 290:2241-60. [DOI: 10.1007/s00438-015-1075-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Accepted: 05/27/2015] [Indexed: 10/23/2022]
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Luo Q, Li Y, Wang W, Fei X, Deng X. Genome-wide survey and expression analysis of Chlamydomonas reinhardtii U-box E3 ubiquitin ligases (CrPUBs) reveal a functional lipid metabolism module. PLoS One 2015; 10:e0122600. [PMID: 25822994 PMCID: PMC4378952 DOI: 10.1371/journal.pone.0122600] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 02/11/2015] [Indexed: 11/18/2022] Open
Abstract
E3 ubiquitin ligases determine the substrate specificity of ubiquitination. Plant U-box (PUB) E3 ligases, with a typical 70-amino acid U-box domain, participate in plant developmental processes and environmental responses. Thus far, 64 PUB proteins have been identified in Arabidopsis and 77 PUB proteins have been identified in Oryza. However, detailed studies on U-box genes in the model microalgae Chlamydomonas reinhardtii are lacking. Here, we present a comprehensive analysis of the genes encoding U-box family proteins in C. reinhardtii. Following BLASTP analysis, 30 full-length U-box genes were identified in the C. reinhardtii genome sequence. Bioinformatics analyses of CrPUB genes were performed to characterize the phylogenetic relationships, chromosomal locations and gene structures of each member. The 30 identified CrPUB proteins are clustered into 3 distinct subfamilies, and the genes for these proteins are unevenly distributed among 14 chromosomes. Furthermore, the quantitative real-time RT-PCR or semi-quantitative RT-PCR analysis of 30 CrPUB mRNA abundances under nitrogen starvation showed that 18 CrPUB genes were induced by N starvation and that 7 genes were repressed in the N-poor environment. We selected five CrPUB genes exhibiting marked changes in expression under N-free conditions for further analysis in RNAi experiments and examined the oil content of these gene-silenced transgenic strains. The silencing of CrPUB5 and CrPUB14, which are typically down-regulated under N starvation, induced 9.8%-45.0% and 14.4%-61.8% lipid accumulation, respectively. In contrast, the silencing of CrPUB11, CrPUB23 and CrPUB28, which are markedly up-regulated under N-free conditions, decreased the lipid content by 5.5%-27.8%, 8.1%-27.3% and 6.6%-27.9%, respectively. These results provide a useful reference for the identification and functional analysis of this gene family and fundamental information for microalgae lipid metabolism research.
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Affiliation(s)
- Qiulan Luo
- Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Science, Haikou, 571101, China
| | - Yajun Li
- Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Science, Haikou, 571101, China
| | - Wenquan Wang
- Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Science, Haikou, 571101, China
| | - Xiaowen Fei
- School of Science, Hainan Medical College, Haikou, 571101, China
| | - Xiaodong Deng
- Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Science, Haikou, 571101, China
- * E-mail:
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Wang J, Qu B, Dou S, Li L, Yin D, Pang Z, Zhou Z, Tian M, Liu G, Xie Q, Tang D, Chen X, Zhu L. The E3 ligase OsPUB15 interacts with the receptor-like kinase PID2 and regulates plant cell death and innate immunity. BMC PLANT BIOLOGY 2015; 15:49. [PMID: 25849162 PMCID: PMC4330927 DOI: 10.1186/s12870-015-0442-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 01/28/2015] [Indexed: 05/20/2023]
Abstract
BACKGROUND Rice blast disease is one of the most destructive diseases of rice worldwide. We previously cloned the rice blast resistance gene Pid2, which encodes a transmembrane receptor-like kinase containing an extracellular B-lectin domain and an intracellular serine/threonine kinase domain. However, little is known about Pid2-mediated signaling. RESULTS Here we report the functional characterization of the U-box/ARM repeat protein OsPUB15 as one of the PID2-binding proteins. We found that OsPUB15 physically interacted with the kinase domain of PID2 (PID2K) in vitro and in vivo and the ARM repeat domain of OsPUB15 was essential for the interaction. In vitro biochemical assays indicated that PID2K possessed kinase activity and was able to phosphorylate OsPUB15. We also found that the phosphorylated form of OsPUB15 possessed E3 ligase activity. Expression pattern analyses revealed that OsPUB15 was constitutively expressed and its encoded protein OsPUB15 was localized in cytosol. Transgenic rice plants over-expressing OsPUB15 at early stage displayed cell death lesions spontaneously in association with a constitutive activation of plant basal defense responses, including excessive accumulation of hydrogen peroxide, up-regulated expression of pathogenesis-related genes and enhanced resistance to blast strains. We also observed that, along with plant growth, the cell death lesions kept spreading over the whole seedlings quickly resulting in a seedling lethal phenotype. CONCLUSIONS These results reveal that the E3 ligase OsPUB15 interacts directly with the receptor-like kinase PID2 and regulates plant cell death and blast disease resistance.
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Affiliation(s)
- Jing Wang
- />State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
- />Rice Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130 China
| | - Baoyuan Qu
- />State Key Laboratory for Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Shijuan Dou
- />College of Life Sciences, Hebei Agricultural University, Baoding, Hebei 071001 China
| | - Liyun Li
- />College of Life Sciences, Hebei Agricultural University, Baoding, Hebei 071001 China
| | - Dedong Yin
- />State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Zhiqian Pang
- />State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
- />CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100029 China
| | - Zhuangzhi Zhou
- />State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Miaomiao Tian
- />State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Guozhen Liu
- />College of Life Sciences, Hebei Agricultural University, Baoding, Hebei 071001 China
| | - Qi Xie
- />State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Dingzhong Tang
- />State Key Laboratory for Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Xuewei Chen
- />Rice Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130 China
| | - Lihuang Zhu
- />State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
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Ludwików A. Targeting proteins for proteasomal degradation-a new function of Arabidopsis ABI1 protein phosphatase 2C. FRONTIERS IN PLANT SCIENCE 2015; 6:310. [PMID: 25999974 PMCID: PMC4419600 DOI: 10.3389/fpls.2015.00310] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 04/19/2015] [Indexed: 05/08/2023]
Abstract
The ubiquitin/26S proteasome system (UPS) has been implicated in the regulation of many physiological processes including hormone signaling. The plant hormone abscisic acid (ABA) employs the UPS to control its own synthesis and signaling and to regulate stress response and tolerance. Among the known effectors of ABA signaling, the ABI1 (abscisic acid-insensitive 1) protein phosphatase, which belongs to group A of the type 2C protein phosphatases, is recognized as a key component of the pathway. Molecular and genetic evidence implicates this protein phosphatase in numerous plant responses. This mini-review discusses recent progress in understanding the role of ABI1 in ABA signaling, with particular emphasis on recent data that link ABI1 to protein degradation via the UPS.
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Affiliation(s)
- Agnieszka Ludwików
- *Correspondence: Agnieszka Ludwików, Department of Biotechnology, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89 Street, Collegium Biologicum, 61-614 Poznan, Poland,
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Callis J. The ubiquitination machinery of the ubiquitin system. THE ARABIDOPSIS BOOK 2014; 12:e0174. [PMID: 25320573 PMCID: PMC4196676 DOI: 10.1199/tab.0174] [Citation(s) in RCA: 211] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The protein ubiquitin is a covalent modifier of proteins, including itself. The ubiquitin system encompasses the enzymes required for catalysing attachment of ubiquitin to substrates as well as proteins that bind to ubiquitinated proteins leading them to their final fate. Also included are activities that remove ubiquitin independent of, or in concert with, proteolysis of the substrate, either by the proteasome or proteases in the vacuole. In addition to ubiquitin encoded by a family of fusion proteins, there are proteins with ubiquitin-like domains, likely forming ubiquitin's β-grasp fold, but incapable of covalent modification. However, they serve as protein-protein interaction platforms within the ubiquitin system. Multi-gene families encode all of these types of activities. Within the ubiquitination machinery "half" of the ubiquitin system are redundant, partially redundant, and unique components affecting diverse developmental and environmental responses in plants. Notably, multiple aspects of biotic and abiotic stress responses require, or are modulated by, ubiquitination. Finally, aspects of the ubiquitin system have broad utility: as components to enhance gene expression or to regulate protein abundance. This review focuses on the ubiquitination machinery: ubiquitin, unique aspects about the synthesis of ubiquitin and organization of its gene family, ubiquitin activating enzymes (E1), ubiquitin conjugating enzymes (E2) and ubiquitin ligases, or E3s. Given the large number of E3s in Arabidopsis this review covers the U box, HECT and RING type E3s, with the exception of the cullin-based E3s.
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Affiliation(s)
- Judy Callis
- Department of Molecular and Cellular Biology, University of California-Davis, Davis CA 95616
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30
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Stone SL. The role of ubiquitin and the 26S proteasome in plant abiotic stress signaling. FRONTIERS IN PLANT SCIENCE 2014; 5:135. [PMID: 24795732 PMCID: PMC3997020 DOI: 10.3389/fpls.2014.00135] [Citation(s) in RCA: 205] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 03/21/2014] [Indexed: 05/18/2023]
Abstract
Ubiquitin is a small, highly conserved, ubiquitously expressed eukaryotic protein with immensely important and diverse regulatory functions. A well-studied function of ubiquitin is its role in selective proteolysis by the ubiquitin-proteasome system (UPS). The UPS has emerged as an integral player in plant response and adaptation to environmental stresses such as drought, salinity, cold and nutrient deprivation. The UPS has also been shown to influence the production and signal transduction of stress-related hormones such as abscisic acid. Understanding UPS function has centered mainly on defining the role of E3 ubiquitin ligases, which are the substrate-recruiting component of the ubiquitination pathway. The recent identification of stress signaling/regulatory proteins that are the subject of ubiquitin-dependent degradation has increased our knowledge of how the UPS facilitates responses to adverse environmental conditions. A brief overview is provided on role of the UPS in modulating protein stability during abiotic stress signaling. E3 ubiquitin ligases for which stress-related substrate proteins have been identified are discussed.
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Affiliation(s)
- Sophia L. Stone
- *Correspondence: Sophia L. Stone, Department of Biology, Dalhousie University, 1355 Oxford Street, P.O. BOX 15000, Halifax, NS B3H 4R2, Canada e-mail:
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Vogelmann K, Subert C, Danzberger N, Drechsel G, Bergler J, Kotur T, Burmester T, Hoth S. Plasma membrane-association of SAUL1-type plant U-box armadillo repeat proteins is conserved in land plants. FRONTIERS IN PLANT SCIENCE 2014; 5:37. [PMID: 24600457 PMCID: PMC3928556 DOI: 10.3389/fpls.2014.00037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 01/27/2014] [Indexed: 05/08/2023]
Abstract
Post-translational protein modification plays a pivotal role in the regulation and specific turnover of proteins. One of these important modifications is the ubiquitination of target proteins, which can occur at distinct cellular compartments. At the plasma membrane, ubiquitination regulates the internalization and thus trafficking of membrane proteins such as receptors and channels. The Arabidopsis plant U-box (PUB) armadillo repeat (PUB-ARM) ubiquitin ligase SAUL1 (SENESCENCE-ASSOCIATED UBIQUITIN LIGASE1) is part of the ubiquitination machinery at the plasma membrane. In contrast to most other PUB-ARM proteins, SAUL1 carries additional C-terminal ARM repeats responsible for plasma membrane-association. Here, we demonstrated that the C-terminal ARM repeat domain is also essential and sufficient to mediate plasma membrane-association of the closest Arabidopis paralog AtPUB43. We investigated targeting of PUB-ARM ubiquitin ligases of different plant species to find out whether plasma membrane-association of SAUL1-type PUB-ARM proteins is conserved. Phylogenetic analysis identified orthologs of SAUL1 in these plant species. Intracellular localization of transiently expressed GFP fusion proteins revealed that indeed plasma membrane-association due to additional C-terminal ARM repeats represents a conserved feature of SAUL1-type proteins. Analyses of transgenic Arabidopsis plants overexpressing N-terminally masked or truncated proteins revealed that interfering with the function of SAUL1-type proteins resulted in severe growth defects. Our results suggest an ancient origin of ubiquitination at the plasma membrane in the evolution of land plants.
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Affiliation(s)
- Katja Vogelmann
- Molekulare Pflanzenphysiologie, Biozentrum Klein Flottbek, Universität HamburgHamburg, Germany
| | - Christa Subert
- Department Biologie, Molekulare Pflanzenphysiologie, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany
| | - Nina Danzberger
- Department Biologie, Molekulare Pflanzenphysiologie, Friedrich-Alexander-Universität Erlangen-NürnbergErlangen, Germany
| | - Gabriele Drechsel
- Zentrum für Molekularbiologie der Pflanzen, Allgemeine Genetik, Universität TübingenTübingen, Germany
| | - Johannes Bergler
- Molekulare Pflanzenphysiologie, Biozentrum Klein Flottbek, Universität HamburgHamburg, Germany
| | - Tanja Kotur
- Molekulare Pflanzenphysiologie, Biozentrum Klein Flottbek, Universität HamburgHamburg, Germany
| | - Thorsten Burmester
- Stoffwechselphysiologie, Biozentrum Grindel, Universität HamburgHamburg, Germany
| | - Stefan Hoth
- Molekulare Pflanzenphysiologie, Biozentrum Klein Flottbek, Universität HamburgHamburg, Germany
- *Correspondence: Stefan Hoth, Molekulare Pflanzenphysiologie, Biozentrum Klein Flottbek, Universität Hamburg, Ohnhorststrasse 18, D-22609 Hamburg, Germany e-mail:
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Ishizaki K, Mizutani M, Shimamura M, Masuda A, Nishihama R, Kohchi T. Essential role of the E3 ubiquitin ligase nopperabo1 in schizogenous intercellular space formation in the liverwort Marchantia polymorpha. THE PLANT CELL 2013; 25:4075-84. [PMID: 24170128 PMCID: PMC3877802 DOI: 10.1105/tpc.113.117051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 09/25/2013] [Accepted: 10/08/2013] [Indexed: 05/17/2023]
Abstract
The vast majority of land plants develop gas-exchange tissues with intercellular spaces (ICSs) connected directly to the air. Although the developmental processes of ICS have been described in detail at the morphological and ultrastructural level in diverse land plants, little is known about the molecular mechanism responsible for ICS formation. The liverwort Marchantia polymorpha develops a multilayered tissue with a large ICS (air chamber), whose formation is initiated at selected positions of epidermal cells. We isolated a mutant of M. polymorpha showing impaired air-chamber formation, nopperabo1 (nop1), from T-DNA-tagged lines. In nop1 plants, no ICS was formed; consequently, a single-layered epidermis developed on the dorsal side of the thallus. The causal gene NOP1 encodes a Plant U-box (PUB) E3 ubiquitin ligase carrying tandem ARMADILLO (ARM) repeats in the C terminus. An in vitro ubiquitination assay indicated that the NOP1 protein possesses E3 ubiquitin ligase activity in a U-box-dependent manner. Confocal microscopy and biochemical analysis showed that NOP1 was localized to the plasma membrane. Our investigation demonstrated the essential role of the PUB-ARM-type ubiquitin ligase in ICS formation in M. polymorpha, which sheds light on the molecular mechanism of schizogenous ICS formation in land plants.
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Affiliation(s)
- Kimitsune Ishizaki
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
- Graduate School of Science, Kobe University, Kobe 657-8501, Japan
| | - Miya Mizutani
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Masaki Shimamura
- Graduate School of Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima 739-8526, Japan
| | - Akihide Masuda
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Ryuichi Nishihama
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Takayuki Kohchi
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
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Abstract
E3 ligases comprise a highly diverse and important group of enzymes that act within the 26S ubiquitin proteasome pathway. They facilitate the transfer of ubiquitin moieties to substrate proteins which may be marked for degradation by this step. As such, they serve as central regulators in many cellular and physiological processes in plants. The review provides an update on the multitude of different E3 ligases currently known in plants, and illustrates the central role in plant biology of specific examples.
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Affiliation(s)
- Liyuan Chen
- Plant Stress Physiology, School of Biological Sciences, Abelson 435, PO Box 644236, Washington State University, Pullman, WA 99164-4236, USA
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Sadanandom A, Bailey M, Ewan R, Lee J, Nelis S. The ubiquitin-proteasome system: central modifier of plant signalling. THE NEW PHYTOLOGIST 2012; 196:13-28. [PMID: 22897362 DOI: 10.1111/j.1469-8137.2012.04266.x] [Citation(s) in RCA: 243] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 07/05/2012] [Indexed: 05/19/2023]
Abstract
Ubiquitin is well established as a major modifier of signalling in eukaryotes. However, the extent to which plants rely on ubiquitin for regulating their lifecycle is only recently becoming apparent. This is underlined by the over-representation of genes encoding ubiquitin-metabolizing enzymes in Arabidopsis when compared with other model eukaryotes. The main characteristic of ubiquitination is the conjugation of ubiquitin onto lysine residues of acceptor proteins. In most cases the targeted protein is rapidly degraded by the 26S proteasome, the major proteolysis machinery in eukaryotic cells. The ubiquitin-proteasome system is responsible for removing most abnormal peptides and short-lived cellular regulators, which, in turn, control many processes. This allows cells to respond rapidly to intracellular signals and changing environmental conditions. This review maps out the roles of the components of the ubiquitin-proteasome system with emphasis on areas where future research is urgently needed. We provide a flavour of the diverse aspects of plant lifecycle where the ubiquitin-proteasome system is implicated. We aim to highlight common themes using key examples that reiterate the importance of the ubiquitin-proteasome system to plants. The future challenge in plant biology is to define the targets for ubiquitination, their interactors and their molecular function within the regulatory context.
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Affiliation(s)
- Ari Sadanandom
- School of Biological and Biomedical Sciences, Durham University, Durham, DH1 3HP, UK
| | - Mark Bailey
- School of Biological and Biomedical Sciences, Durham University, Durham, DH1 3HP, UK
| | - Richard Ewan
- The Scottish Institute for Cell Signalling (SCILLS), Sir James Black Centre, University of Dundee, Dundee, DD1 5EH, UK
| | - Jack Lee
- School of Biological and Biomedical Sciences, Durham University, Durham, DH1 3HP, UK
| | - Stuart Nelis
- School of Biological and Biomedical Sciences, Durham University, Durham, DH1 3HP, UK
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35
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Guerra DD, Callis J. Ubiquitin on the move: the ubiquitin modification system plays diverse roles in the regulation of endoplasmic reticulum- and plasma membrane-localized proteins. PLANT PHYSIOLOGY 2012; 160:56-64. [PMID: 22730427 PMCID: PMC3440229 DOI: 10.1104/pp.112.199869] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
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36
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Seo DH, Ryu MY, Jammes F, Hwang JH, Turek M, Kang BG, Kwak JM, Kim WT. Roles of four Arabidopsis U-box E3 ubiquitin ligases in negative regulation of abscisic acid-mediated drought stress responses. PLANT PHYSIOLOGY 2012; 160:556-68. [PMID: 22829319 PMCID: PMC3440228 DOI: 10.1104/pp.112.202143] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 07/21/2012] [Indexed: 05/19/2023]
Abstract
AtPUB18 and AtPUB19 are homologous U-box E3 ubiquitin ligases in Arabidopsis (Arabidopsis thaliana). AtPUB19 is a negative regulator of abscisic acid (ABA)-mediated drought responses, whereas the role of AtPUB18 in drought responses is unknown. Here, loss-of-function and overexpression tests identified AtPUB18 as a negative regulator in ABA-mediated stomatal closure and water stress responses. The atpub18-2atpub19-3 double mutant line displayed more sensitivity to ABA and enhanced drought tolerance than each single mutant plant; therefore, AtPUB18 and AtPUB19 are agonistic. Stomatal closure of the atpub18-2atpub19-3 mutant was hypersensitive to hydrogen peroxide (H(2)O(2)) but not to calcium, suggesting that AtPUB18 and AtPUB19 exert negative effects on the ABA signaling pathway downstream of H(2)O(2) and upstream of calcium. AtPUB22 and AtPUB23 are other U-box E3 negative regulators of drought responses. Although atpub22atpub23 was more tolerant to drought stress relative to wild-type plants, its ABA-mediated stomatal movements were highly similar to those of wild-type plants. The atpub18-2atpub19-3atpub22atpub23 quadruple mutant exhibited enhanced tolerance to drought stress as compared with each atpub18-2atpub19-3 and atpub22atpub23 double mutant progeny; however, its stomatal behavior was almost identical to the atpub18-2atpub19-3 double mutant in the presence of ABA, H(2)O(2), and calcium. Overexpression of AtPUB18 and AtPUB19 in atpub22atpub23 effectively hindered ABA-dependent stomatal closure, but overexpression of AtPUB22 and AtPUB23 in atpub18-2atpub19-3 did not inhibit ABA-enhanced stomatal closure, highlighting their ABA-independent roles. Overall, these results suggest that AtPUB18 has a linked function with AtPUB19, but is independent from AtPUB22 and AtPUB23, in negative regulation of ABA-mediated drought stress responses.
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Vogelmann K, Drechsel G, Bergler J, Subert C, Philippar K, Soll J, Engelmann JC, Engelsdorf T, Voll LM, Hoth S. Early senescence and cell death in Arabidopsis saul1 mutants involves the PAD4-dependent salicylic acid pathway. PLANT PHYSIOLOGY 2012; 159:1477-87. [PMID: 22706448 PMCID: PMC3425192 DOI: 10.1104/pp.112.196220] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 06/14/2012] [Indexed: 05/21/2023]
Abstract
Age-dependent leaf senescence and cell death in Arabidopsis (Arabidopsis thaliana) requires activation of the transcription factor ORESARA1 (ORE1) and is not initiated prior to a leaf age of 28 d. Here, we investigate the conditional execution of events that regulate early senescence and cell death in senescence-associated ubiquitin ligase1 (saul1) mutants, deficient in the PLANT U-BOX-ARMADILLO E3 ubiquitin ligase SAUL1. In saul1 mutants challenged with low light, the switch of age-dependent cell death was turned on prematurely, as indicated by the accumulation of ORE1 transcripts, induction of the senescence marker gene SENESCENCE-ASSOCIATED GENE12, and cell death. However, ORE1 accumulation by itself was not sufficient to cause saul1 phenotypes, as demonstrated by double mutant analysis. Exposure of saul1 mutants to low light for only 24 h did not result in visible symptoms of senescence; however, the senescence-promoting transcription factor genes WRKY53, WRKY6, and NAC-LIKE ACTIVATED BY AP3/PI were up-regulated, indicating that senescence in saul1 seedlings was already initiated. To resolve the time course of gene expression, microarray experiments were performed at narrow intervals. Differential expression of the genes involved in salicylic acid and defense mechanisms were the earliest events detected, suggesting a central role for salicylic acid in saul1 senescence and cell death. The salicylic acid content increased in low-light-treated saul1 mutants, and application of exogenous salicylic acid was indeed sufficient to trigger saul1 senescence in permissive light conditions. Double mutant analyses showed that PHYTOALEXIN DEFICIENT4 (PAD4) but not NONEXPRESSER OF PR GENES1 (NPR1) is essential for saul1 phenotypes. Our results indicate that saul1 senescence depends on the PAD4-dependent salicylic acid pathway but does not require NPR1 signaling.
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Cho SK, Ryu MY, Seo DH, Kang BG, Kim WT. The Arabidopsis RING E3 ubiquitin ligase AtAIRP2 plays combinatory roles with AtAIRP1 in abscisic acid-mediated drought stress responses. PLANT PHYSIOLOGY 2011; 157:2240-57. [PMID: 21969385 PMCID: PMC3327188 DOI: 10.1104/pp.111.185595] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The ubiquitin (Ub)-26S proteasome pathway is implicated in various cellular processes in higher plants. AtAIRP1, a C3H2C3-type RING (for Really Interesting New Gene) E3 Ub ligase, is a positive regulator in the Arabidopsis (Arabidopsis thaliana) abscisic acid (ABA)-dependent drought response. Here, the AtAIRP2 (for Arabidopsis ABA-insensitive RING protein 2) gene was identified and characterized. AtAIRP2 encodes a cytosolic C3HC4-type RING E3 Ub ligase whose expression was markedly induced by ABA and dehydration stress. Thus, AtAIRP2 belongs to a different RING subclass than AtAIRP1 with a limited sequence identity. AtAIRP2-overexpressing transgenic (35S:AtAIRP2-sGFP) and atairp2 loss-of-function mutant plants exhibited hypersensitive and hyposensitive phenotypes, respectively, to ABA in terms of seed germination, root growth, and stomatal movement. 35S:AtAIRP2-sGFP plants were highly tolerant to severe drought stress, and atairp2 alleles were more susceptible to water stress than were wild-type plants. Higher levels of drought-induced hydrogen peroxide production were detected in 35S:AtAIRP2-sGFP as compared with atairp2 plants. ABA-inducible drought-related genes were up-regulated in 35S:AtAIRP2-sGFP and down-regulated in atairp2 progeny. The positive effects of AtAIRP2 on ABA-induced stress genes were dependent on SNF1-related protein kinases, key components of the ABA signaling pathway. Therefore, AtAIRP2 is involved in positive regulation of ABA-dependent drought stress responses. To address the functional relationship between AtAIRP1 and AtAIRP2, FLAG-AtAIRP1 and AtAIRP2-sGFP genes were ectopically expressed in atairp2-2 and atairp1 plants, respectively. Constitutive expression of FLAG-AtAIRP1 and AtAIRP2-sGFP in atairp2-2 and atairp1 plants, respectively, reciprocally rescued the loss-of-function ABA-insensitive phenotypes during germination. Additionally, atairp1/35S:AtAIRP2-sGFP and atairp2-2/35S:FLAG-AtAIRP1 complementation lines were more tolerant to dehydration stress relative to atairp1 and atairp2-2 single knockout plants. Overall, these results suggest that AtAIRP2 plays combinatory roles with AtAIRP1 in Arabidopsis ABA-mediated drought stress responses.
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