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Yao H, Gao S, Sun T, Zhou G, Lu C, Gao B, Chen W, Liang Y. Transcriptomic analysis of the defense response in "Cabernet Sauvignon" grape leaf induced by Apolygus lucorum feeding. PLANT DIRECT 2024; 8:e590. [PMID: 38779180 PMCID: PMC11108798 DOI: 10.1002/pld3.590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 02/14/2024] [Accepted: 04/10/2024] [Indexed: 05/25/2024]
Abstract
To investigate the molecular mechanism of the defense response of "Cabernet Sauvignon" grapes to feeding by Apolygus lucorum, high-throughput sequencing technology was used to analyze the transcriptome of grape leaves under three different treatments: feeding by A. lucorum, puncture injury, and an untreated control. The research findings indicated that the differentially expressed genes were primarily enriched in three aspects: cellular composition, molecular function, and biological process. These genes were found to be involved in 42 metabolic pathways, particularly in plant hormone signaling metabolism, plant-pathogen interaction, MAPK signaling pathway, and other metabolic pathways associated with plant-induced insect resistance. Feeding by A. lucorum stimulated and upregulated a significant number of genes related to jasmonic acid and calcium ion pathways, suggesting their crucial role in the defense molecular mechanism of "Cabernet Sauvignon" grapes. The consistency between the gene expression and transcriptome sequencing results further supports these findings. This study provides a reference for the further exploration of the defense response in "Cabernet Sauvignon" grapes by elucidating the expression of relevant genes during feeding by A. lucorum.
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Affiliation(s)
- Heng Yao
- College of Agronomy and BiotechnologyHebei Normal University of Science and TechnologyChangliHebeiChina
- Hebei Key Laboratory of Crop Stress Biology (in Preparation)ChangliHebeiChina
| | - Suhong Gao
- College of Agronomy and BiotechnologyHebei Normal University of Science and TechnologyChangliHebeiChina
- Hebei Key Laboratory of Crop Stress Biology (in Preparation)ChangliHebeiChina
| | - Tianhua Sun
- College of ForestryHebei Agricultural UniversityBaodingHebeiChina
| | - Guona Zhou
- College of ForestryHebei Agricultural UniversityBaodingHebeiChina
| | - Changkuan Lu
- College of Agronomy and BiotechnologyHebei Normal University of Science and TechnologyChangliHebeiChina
| | - Baojia Gao
- College of ForestryHebei Agricultural UniversityBaodingHebeiChina
| | - Wenshu Chen
- College of Agronomy and BiotechnologyHebei Normal University of Science and TechnologyChangliHebeiChina
- Hebei Key Laboratory of Crop Stress Biology (in Preparation)ChangliHebeiChina
| | - Yiming Liang
- College of Agronomy and BiotechnologyHebei Normal University of Science and TechnologyChangliHebeiChina
- Hebei Key Laboratory of Crop Stress Biology (in Preparation)ChangliHebeiChina
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2
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Hartman MD, Rojas BE, Ferrero DML, Leyva A, Durán R, Iglesias AA, Figueroa CM. Phosphorylation of aldose-6-phosphate reductase from Prunus persica leaves. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 194:461-469. [PMID: 36508780 DOI: 10.1016/j.plaphy.2022.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 11/04/2022] [Accepted: 12/05/2022] [Indexed: 06/17/2023]
Abstract
Sugar-alcohols are major photosynthates in plants from the Rosaceae family. Expression of the gene encoding aldose-6-phosphate reductase (Ald6PRase), the critical enzyme for glucitol synthesis in rosaceous species, is regulated by physiological and environmental cues. Additionally, Ald6PRase is inhibited by small molecules (hexose-phosphates and inorganic orthophosphate) and oxidizing compounds. This work demonstrates that Ald6PRase from peach leaves is phosphorylated in planta at the N-terminus. We also show in vitro phosphorylation of recombinant Ald6PRase by a partially purified kinase extract from peach leaves containing Ca2+-dependent protein kinases (CDPKs). Moreover, phosphorylation of recombinant Ald6PRase was inhibited by hexose-phosphates, phosphoenolpyruvate and pyrophosphate. We further show that phosphorylation of recombinant Ald6PRase was maximal using recombinant CDPKs. Overall, our results suggest that phosphorylation could fine-tune the activity of Ald6PRase.
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Affiliation(s)
- Matías D Hartman
- Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Santa Fe, Argentina
| | - Bruno E Rojas
- Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Santa Fe, Argentina
| | - Danisa M L Ferrero
- Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Santa Fe, Argentina
| | - Alejandro Leyva
- Unidad de Bioquímica y Proteómica Analíticas, Instituto de Investigaciones Biológicas Clemente Estable and Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Rosario Durán
- Unidad de Bioquímica y Proteómica Analíticas, Instituto de Investigaciones Biológicas Clemente Estable and Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Alberto A Iglesias
- Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Santa Fe, Argentina
| | - Carlos M Figueroa
- Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Santa Fe, Argentina.
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3
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Hu Y, Liu J, Lin Y, Xu X, Xia Y, Bai J, Yu Y, Xiao F, Ding Y, Ding C, Chen L. Sucrose nonfermenting-1-related protein kinase 1 regulates sheath-to-panicle transport of nonstructural carbohydrates during rice grain filling. PLANT PHYSIOLOGY 2022; 189:1694-1714. [PMID: 35294032 PMCID: PMC9237689 DOI: 10.1093/plphys/kiac124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 02/22/2022] [Indexed: 05/05/2023]
Abstract
The remobilization of nonstructural carbohydrates (NSCs) reserved in rice (Oryza sativa) sheaths is essential for grain filling. This assimilate distribution between plant tissues and organs is determined by sucrose non-fermenting-1-related protein kinase 1 (SnRK1). However, the SnRK1-mediated mechanism regulating the sheath-to-panicle transport of NSCs in rice remains unknown. In this study, leaf cutting treatment was used to accelerate NSC transport in the rice sheaths. Accelerated NSC transport was accompanied by increased levels of OsSnRK1a mRNA expression, SnRK1a protein expression, catalytic subunit phosphorylation of SnRK1, and SnRK1 activity, indicating that SnRK1 activity plays an important role in sheath NSC transport. We also discovered that trehalose-6-phosphate, a signal of sucrose availability, slightly reduced SnRK1 activity in vitro. Since SnRK1 activity is mostly regulated by OsSnRK1a transcription in response to low sucrose content, we constructed an snrk1a mutant to verify the function of SnRK1 in NSC transport. NSCs accumulated in the sheaths of snrk1a mutant plants and resulted in a low seed setting rate and grain weight, verifying that SnRK1 activity is essential for NSC remobilization. Using phosphoproteomics and parallel reaction monitoring, we identified 20 SnRK1-dependent phosphosites that are involved in NSC transport. In addition, the SnRK1-mediated phosphorylation of the phosphosites directly affected starch degradation, sucrose metabolism, phloem transport, sugar transport across the tonoplast, and glycolysis in rice sheaths to promote NSC transport. Therefore, our findings reveal the importance, function, and possible regulatory mechanism of SnRK1 in the sheath-to-panicle transport of NSCs in rice.
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Affiliation(s)
- Yuxiang Hu
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Jiajun Liu
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Yan Lin
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Xuemei Xu
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Yongqing Xia
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Jiaqi Bai
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Yongchao Yu
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Feng Xiao
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Yanfeng Ding
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
- Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | | | - Lin Chen
- Authors for correspondence: (L.C); (C.D.)
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Kumar S, Thakur M, Mitra R, Basu S, Anand A. Sugar metabolism during pre- and post-fertilization events in plants under high temperature stress. PLANT CELL REPORTS 2022; 41:655-673. [PMID: 34628530 DOI: 10.1007/s00299-021-02795-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 09/24/2021] [Indexed: 06/13/2023]
Abstract
High temperature challenges global crop production by limiting the growth and development of the reproductive structures and seed. It impairs the developmental stages of male and female gametogenesis, pollination, fertilization, endosperm formation and embryo development. Among these, the male reproductive processes are highly prone to abnormalities under high temperature at various stages of development. The disruption of source-sink balance is the main constraint for satisfactory growth of the reproductive structures which is disturbed at the level of sucrose import and utilization within the tissue. Seed development after fertilization is affected by modulation in the activity of enzymes involved in starch metabolism. In addition, the alteration in the seed-filling rate and its duration affects the seed weight and quality. The present review critically discusses the role of sugar metabolism in influencing the various stages of gamete and seed development under high temperature stress. It also highlights the interaction of the sugars with hormones that mediate the transport of sugars to sink tissues. The role of transcription factors for the regulation of sugar availability under high temperature has also been discussed. Further, the omics-based systematic investigation has been suggested to understand the synergistic or antagonistic interactions between sugars, hormones and reactive oxygen species at various points of sucrose flow from source to sink under high temperature stress.
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Affiliation(s)
- Sunil Kumar
- Division of Seed Science and Technology, ICAR- Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Meenakshi Thakur
- College of Horticulture and Forestry, Dr. Y.S. Parmar University of Horticulture and Forestry, Neri, Hamirpur, 177 001, Himachal Pradesh, India
| | - Raktim Mitra
- Division of Plant Physiology, ICAR-Indian Agricultural Research Institute, New Delhi, 110 012, India
| | - Sudipta Basu
- Division of Seed Science and Technology, ICAR- Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Anjali Anand
- Division of Plant Physiology, ICAR-Indian Agricultural Research Institute, New Delhi, 110 012, India.
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Chen Z, Zhou L, Jiang P, Lu R, Halford NG, Liu C. Genome-wide identification of sucrose nonfermenting-1-related protein kinase (SnRK) genes in barley and RNA-seq analyses of their expression in response to abscisic acid treatment. BMC Genomics 2021; 22:300. [PMID: 33902444 PMCID: PMC8074225 DOI: 10.1186/s12864-021-07601-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 04/11/2021] [Indexed: 01/21/2023] Open
Abstract
Background Sucrose nonfermenting-1 (SNF1)-related protein kinases (SnRKs) play important roles in regulating metabolism and stress responses in plants, providing a conduit for crosstalk between metabolic and stress signalling, in some cases involving the stress hormone, abscisic acid (ABA). The burgeoning and divergence of the plant gene family has led to the evolution of three subfamilies, SnRK1, SnRK2 and SnRK3, of which SnRK2 and SnRK3 are unique to plants. Therefore, the study of SnRKs in crops may lead to the development of strategies for breeding crop varieties that are more resilient under stress conditions. In the present study, we describe the SnRK gene family of barley (Hordeum vulgare), the widespread cultivation of which can be attributed to its good adaptation to different environments. Results The barley HvSnRK gene family was elucidated in its entirety from publicly-available genome data and found to comprise 50 genes. Phylogenetic analyses assigned six of the genes to the HvSnRK1 subfamily, 10 to HvSnRK2 and 34 to HvSnRK3. The search was validated by applying it to Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) genome data, identifying 50 SnRK genes in rice (four OsSnRK1, 11 OsSnRK2 and 35 OsSnRK3) and 39 in Arabidopsis (three AtSnRK1, 10 AtSnRK2 and 26 AtSnRK3). Specific motifs were identified in the encoded barley proteins, and multiple putative regulatory elements were found in the gene promoters, with light-regulated elements (LRE), ABA response elements (ABRE) and methyl jasmonate response elements (MeJa) the most common. RNA-seq analysis showed that many of the HvSnRK genes responded to ABA, some positively, some negatively and some with complex time-dependent responses. Conclusions The barley HvSnRK gene family is large, comprising 50 members, subdivided into HvSnRK1 (6 members), HvSnRK2 (10 members) and HvSnRK3 (34 members), showing differential positive and negative responses to ABA. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07601-6.
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Affiliation(s)
- Zhiwei Chen
- Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, 201106, China.,Shanghai Key Laboratory of Agricultural Genetics and Breeding, Shanghai, 201106, China
| | - Longhua Zhou
- Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, 201106, China.,Shanghai Key Laboratory of Agricultural Genetics and Breeding, Shanghai, 201106, China
| | - Panpan Jiang
- Shenzhen RealOm ics (Biotech) Co., Ltd., Shenzhen, 518081, China
| | - Ruiju Lu
- Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, 201106, China.,Shanghai Key Laboratory of Agricultural Genetics and Breeding, Shanghai, 201106, China
| | - Nigel G Halford
- Plant Sciences Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Chenghong Liu
- Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, 201106, China. .,Shanghai Key Laboratory of Agricultural Genetics and Breeding, Shanghai, 201106, China.
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6
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Sucrose interferes with endogenous cytokinin homeostasis and expression of organogenesis-related genes during de novo shoot organogenesis in kohlrabi. Sci Rep 2021; 11:6494. [PMID: 33753792 PMCID: PMC7985405 DOI: 10.1038/s41598-021-85932-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 03/08/2021] [Indexed: 11/12/2022] Open
Abstract
Cross-talk between phytohormones and sugars is intensely involved in plant metabolism, growth and regeneration. We documented alterations in cytokinin (CK) homeostasis in four developmental stages during de novo shoot organogenesis (DNSO) of kohlrabi (Brassica oleracea var. gongylodes cv. Vienna Purple) seedlings induced by exogenous CKs, trans-zeatin (transZ) and thidiazuron (TDZ), added together with elevated sucrose concentration (6% and 9%). Significant impact of CK and sucrose treatment and their interaction was recorded in all investigated stages, including plantlet development before calli formation (T1 and T2), calli formation (T3) and shoot regeneration (T4). Results showed remarkable increase in total CK levels for transZ treatment, particularly with 9% sucrose. This trend was observed for all physiological and structural groups of CKs. Application of TDZ contributed to little or no increase in CK levels regardless of sucrose concentration. Analysis of expression profiles of organogenesis-related genes involved in auxin transport, CK response, shoot apical meristem formation and cell division revealed that higher sugar concentration significantly downregulated the analysed genes, particularly in T3. This continued on TDZ, but transZ induced an opposite effect with 9% sucrose in T4, increasing gene activity. Our results demonstrated that phytohormone metabolism might be triggered by sucrose signalling in kohlrabi DNSO.
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Jamsheer K M, Jindal S, Laxmi A. Evolution of TOR-SnRK dynamics in green plants and its integration with phytohormone signaling networks. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2239-2259. [PMID: 30870564 DOI: 10.1093/jxb/erz107] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/26/2019] [Indexed: 05/07/2023]
Abstract
The target of rapamycin (TOR)-sucrose non-fermenting 1 (SNF1)-related protein kinase 1 (SnRK1) signaling is an ancient regulatory mechanism that originated in eukaryotes to regulate nutrient-dependent growth. Although the TOR-SnRK1 signaling cascade shows highly conserved functions among eukaryotes, studies in the past two decades have identified many important plant-specific innovations in this pathway. Plants also possess SnRK2 and SnRK3 kinases, which originated from the ancient SnRK1-related kinases and have specialized roles in controlling growth, stress responses and nutrient homeostasis in plants. Recently, an integrative picture has started to emerge in which different SnRKs and TOR kinase are highly interconnected to control nutrient and stress responses of plants. Further, these kinases are intimately involved with phytohormone signaling networks that originated at different stages of plant evolution. In this review, we highlight the evolution and divergence of TOR-SnRK signaling components in plants and their communication with each other as well as phytohormone signaling to fine-tune growth and stress responses in plants.
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Affiliation(s)
- Muhammed Jamsheer K
- Amity Food & Agriculture Foundation, Amity University Uttar Pradesh, Noida, India
| | - Sunita Jindal
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, India
| | - Ashverya Laxmi
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, India
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Sakr S, Wang M, Dédaldéchamp F, Perez-Garcia MD, Ogé L, Hamama L, Atanassova R. The Sugar-Signaling Hub: Overview of Regulators and Interaction with the Hormonal and Metabolic Network. Int J Mol Sci 2018; 57:2367-2379. [PMID: 30149541 DOI: 10.1093/pcp/pcw157] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/07/2018] [Accepted: 09/05/2016] [Indexed: 05/25/2023] Open
Abstract
Plant growth and development has to be continuously adjusted to the available resources. Their optimization requires the integration of signals conveying the plant metabolic status, its hormonal balance, and its developmental stage. Many investigations have recently been conducted to provide insights into sugar signaling and its interplay with hormones and nitrogen in the fine-tuning of plant growth, development, and survival. The present review emphasizes the diversity of sugar signaling integrators, the main molecular and biochemical mechanisms related to the sugar-signaling dependent regulations, and to the regulatory hubs acting in the interplay of the sugar-hormone and sugar-nitrogen networks. It also contributes to compiling evidence likely to fill a few knowledge gaps, and raises new questions for the future.
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Affiliation(s)
- Soulaiman Sakr
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Ming Wang
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Fabienne Dédaldéchamp
- Equipe "Sucres & Echanges Végétaux-Environnement", Ecologie et Biologie des Interactions, Université de Poitiers, UMR CNRS 7267 EBI, Bâtiment B31, 3 rue Jacques Fort, TSA 51106, 86073 Poitiers CEDEX 9, France.
| | - Maria-Dolores Perez-Garcia
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Laurent Ogé
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Latifa Hamama
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Rossitza Atanassova
- Equipe "Sucres & Echanges Végétaux-Environnement", Ecologie et Biologie des Interactions, Université de Poitiers, UMR CNRS 7267 EBI, Bâtiment B31, 3 rue Jacques Fort, TSA 51106, 86073 Poitiers CEDEX 9, France.
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9
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Sakr S, Wang M, Dédaldéchamp F, Perez-Garcia MD, Ogé L, Hamama L, Atanassova R. The Sugar-Signaling Hub: Overview of Regulators and Interaction with the Hormonal and Metabolic Network. Int J Mol Sci 2018; 19:ijms19092506. [PMID: 30149541 PMCID: PMC6165531 DOI: 10.3390/ijms19092506] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 08/07/2018] [Accepted: 08/13/2018] [Indexed: 12/31/2022] Open
Abstract
Plant growth and development has to be continuously adjusted to the available resources. Their optimization requires the integration of signals conveying the plant metabolic status, its hormonal balance, and its developmental stage. Many investigations have recently been conducted to provide insights into sugar signaling and its interplay with hormones and nitrogen in the fine-tuning of plant growth, development, and survival. The present review emphasizes the diversity of sugar signaling integrators, the main molecular and biochemical mechanisms related to the sugar-signaling dependent regulations, and to the regulatory hubs acting in the interplay of the sugar-hormone and sugar-nitrogen networks. It also contributes to compiling evidence likely to fill a few knowledge gaps, and raises new questions for the future.
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Affiliation(s)
- Soulaiman Sakr
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Ming Wang
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Fabienne Dédaldéchamp
- Equipe "Sucres & Echanges Végétaux-Environnement", Ecologie et Biologie des Interactions, Université de Poitiers, UMR CNRS 7267 EBI, Bâtiment B31, 3 rue Jacques Fort, TSA 51106, 86073 Poitiers CEDEX 9, France.
| | - Maria-Dolores Perez-Garcia
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Laurent Ogé
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Latifa Hamama
- Institut de Recherche en Horticulture et Semences, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QUASAV, F-49045 Angers, France.
| | - Rossitza Atanassova
- Equipe "Sucres & Echanges Végétaux-Environnement", Ecologie et Biologie des Interactions, Université de Poitiers, UMR CNRS 7267 EBI, Bâtiment B31, 3 rue Jacques Fort, TSA 51106, 86073 Poitiers CEDEX 9, France.
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10
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Luang S, Sornaraj P, Bazanova N, Jia W, Eini O, Hussain SS, Kovalchuk N, Agarwal PK, Hrmova M, Lopato S. The wheat TabZIP2 transcription factor is activated by the nutrient starvation-responsive SnRK3/CIPK protein kinase. PLANT MOLECULAR BIOLOGY 2018; 96:543-561. [PMID: 29564697 DOI: 10.1007/s11103-018-0713-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 02/23/2018] [Indexed: 05/09/2023]
Abstract
The understanding of roles of bZIP factors in biological processes during plant development and under abiotic stresses requires the detailed mechanistic knowledge of behaviour of TFs. Basic leucine zipper (bZIP) transcription factors (TFs) play key roles in the regulation of grain development and plant responses to abiotic stresses. We investigated the role and molecular mechanisms of function of the TabZIP2 gene isolated from drought-stressed wheat plants. Molecular characterisation of TabZIP2 and derived protein included analyses of gene expression and its target promoter, and the influence of interacting partners on the target promoter activation. Two interacting partners of TabZIP2, the 14-3-3 protein, TaWIN1 and the bZIP transcription factor TaABI5L, were identified in a Y2H screen. We established that under elevated ABA levels the activity of TabZIP2 was negatively regulated by the TaWIN1 protein and positively regulated by the SnRK3/CIPK protein kinase WPK4, reported previously to be responsive to nutrient starvation. The physical interaction between the TaWIN1 and the WPK4 was detected. We also compared the influence of homo- and hetero-dimerisation of TabZIP2 and TaABI5L on DNA binding. TabZIP2 gene functional analyses were performed using drought-inducible overexpression of TabZIP2 in transgenic wheat. Transgenic plants grown under moderate drought during flowering, were smaller than control plants, and had fewer spikes and seeds per plant. However, a single seed weight was increased compared to single seed weights of control plants in three of four evaluated transgenic lines. The observed phenotypes of transgenic plants and the regulation of TabZIP2 activity by nutrient starvation-responsive WPK4, suggest that the TabZIP2 could be the part of a signalling pathway, which controls the rearrangement of carbohydrate and nutrient flows in plant organs in response to drought.
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Affiliation(s)
- Sukanya Luang
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, 5064, Australia
- Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand
| | - Pradeep Sornaraj
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, 5064, Australia
| | - Natalia Bazanova
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, 5064, Australia
- Commonwealth Scientific and Industrial Research Organisation, Glen Osmond, SA, 5064, Australia
| | - Wei Jia
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, 5064, Australia
| | - Omid Eini
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, 5064, Australia
- Department of Plant Protection, School of Agriculture, University of Zanjan, Zanjan, Iran
| | - Syed Sarfraz Hussain
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, 5064, Australia
- Forman Christian College, Lahore, 54600, Pakistan
| | - Nataliya Kovalchuk
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, 5064, Australia
| | - Pradeep K Agarwal
- CSIR-Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar, India
| | - Maria Hrmova
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, 5064, Australia.
| | - Sergiy Lopato
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, 5064, Australia
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Piattoni CV, Ferrero DML, Dellaferrera I, Vegetti A, Iglesias AÁ. Cytosolic Glyceraldehyde-3-Phosphate Dehydrogenase Is Phosphorylated during Seed Development. FRONTIERS IN PLANT SCIENCE 2017; 8:522. [PMID: 28443115 PMCID: PMC5387080 DOI: 10.3389/fpls.2017.00522] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 03/23/2017] [Indexed: 05/06/2023]
Abstract
Cytosolic glyceraldehyde-3-phosphate dehydrogenase (NAD-GAPDH) is involved in a critical energetic step of glycolysis and also has many important functions besides its enzymatic activity. The recombinant wheat NAD-GAPDH was phosphorylated in vitro at Ser205 by a SNF1-Related protein kinase 1 (SnRK1) from wheat heterotrophic (but not from photosynthetic) tissues. The S205D mutant enzyme (mimicking the phosphorylated form) exhibited a significant decrease in activity but similar affinity toward substrates. Immunodetection and activity assays showed that NAD-GAPDH is phosphorylated in vivo, the enzyme depicting different activity, abundance and phosphorylation profiles during development of seeds that mainly accumulate starch (wheat) or lipids (castor oil seed). NAD-GAPDH activity gradually increases along wheat seed development, but protein levels and phosphorylation status exhibited slight changes. Conversely, in castor oil seed, the activity slightly increased and total protein levels do not significantly change in the first half of seed development but both abruptly decreased in the second part of development, when triacylglycerol synthesis and storage begin. Interestingly, phospho-NAD-GAPDH levels reached a maximum when the seed switch their metabolism to mainly support synthesis and accumulation of carbon reserves. After this point the castor oil seed NAD-GAPDH protein levels and activity highly decreased, and the protein stability assays showed that the protein would be degraded by the proteasome. The results presented herein suggest that phosphorylation of NAD-GAPDH during seed development would have impact on the partitioning of triose-phosphate between different metabolic pathways and cell compartments to support the specific carbon, energy and reducing equivalent demands during synthesis of storage products.
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Affiliation(s)
- Claudia V. Piattoni
- Laboratorio de Enzimología Molecular, Instituto de Agrobiotecnología del Litoral (Consejo Nacional de Investigaciones Científicas y Técnicas – Universidad Nacional del Litoral) and Facultad de Bioquímica y Ciencias Biológicas (Universidad Nacional del Litoral), Centro Científico Tecnológico, Consejo Nacional de Investigaciones Científicas y Técnicas Santa FeSanta Fe, Argentina
- *Correspondence: Alberto Á. Iglesias, Claudia V. Piattoni,
| | - Danisa M. L. Ferrero
- Laboratorio de Enzimología Molecular, Instituto de Agrobiotecnología del Litoral (Consejo Nacional de Investigaciones Científicas y Técnicas – Universidad Nacional del Litoral) and Facultad de Bioquímica y Ciencias Biológicas (Universidad Nacional del Litoral), Centro Científico Tecnológico, Consejo Nacional de Investigaciones Científicas y Técnicas Santa FeSanta Fe, Argentina
| | - Ignacio Dellaferrera
- Cultivos Extensivos, Facultad de Ciencias Agrarias, Universidad Nacional del Litoral, EsperanzaArgentina
| | - Abelardo Vegetti
- Morfología Vegetal, Facultad de Ciencias Agrarias, Universidad Nacional del Litoral, EsperanzaArgentina
| | - Alberto Á. Iglesias
- Laboratorio de Enzimología Molecular, Instituto de Agrobiotecnología del Litoral (Consejo Nacional de Investigaciones Científicas y Técnicas – Universidad Nacional del Litoral) and Facultad de Bioquímica y Ciencias Biológicas (Universidad Nacional del Litoral), Centro Científico Tecnológico, Consejo Nacional de Investigaciones Científicas y Técnicas Santa FeSanta Fe, Argentina
- *Correspondence: Alberto Á. Iglesias, Claudia V. Piattoni,
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12
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Kushwah S, Laxmi A. The interaction between glucose and cytokinin signal transduction pathway in Arabidopsis thaliana. PLANT, CELL & ENVIRONMENT 2014; 37:235-53. [PMID: 23763631 DOI: 10.1111/pce.12149] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2013] [Accepted: 05/20/2013] [Indexed: 05/07/2023]
Abstract
Cytokinins (CKs) and glucose (GLC) control a number of common responses in plants. We hypothesize that there may be an extensive overlap between CK- and GLC-signalling pathways. Microarray along with physiological analysis has been performed to find out the interdependence/overlap between CK and GLC signal transduction pathways in Arabidopsis seedlings. GLC could transcriptionally affect 76% of CK-regulated genes at whole genome level, 89% of which are agonistically regulated. GLC may also affect CK-regulated gene expression via non-transcriptional pathways. GLC can regulate several genes involved in CK metabolism and signalling. A number of gene families involved in development and stress are commonly regulated by CK and GLC. Physiologically, both GLC and CK could regulate hypocotyl length in dark. GLC and CK signalling may integrate at the level of type A Arabidopsis response regulators (ARRs) in controlling hypocotyl length. Both GLC and CK signalling cannot alter hypocotyl length in dark in auxin-signalling mutants auxin response2/indole-3-acetic acid7 (AXR2/IAA7) and AXR3/IAA17 suggesting that they may involve auxin-signalling component as a nodal point. Here, we demonstrate that there is an extensive overlap between CK- and GLC-regulated gene expression and physiological responses.
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Affiliation(s)
- Sunita Kushwah
- National Institute of Plant Genome Research, Aruna Asaf Ali Road, New Delhi, 110067, India
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13
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Deng X, Hu W, Wei S, Zhou S, Zhang F, Han J, Chen L, Li Y, Feng J, Fang B, Luo Q, Li S, Liu Y, Yang G, He G. TaCIPK29, a CBL-interacting protein kinase gene from wheat, confers salt stress tolerance in transgenic tobacco. PLoS One 2013; 8:e69881. [PMID: 23922838 PMCID: PMC3726728 DOI: 10.1371/journal.pone.0069881] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 06/14/2013] [Indexed: 12/29/2022] Open
Abstract
Calcineurin B-like protein-interacting protein kinases (CIPKs) have been found to be responsive to abiotic stress. However, their precise functions and the related molecular mechanisms in abiotic stress tolerance are not completely understood, especially in wheat. In the present study, TaCIPK29 was identified as a new member of CIPK gene family in wheat. TaCIPK29 transcript increased after NaCl, cold, methyl viologen (MV), abscisic acid (ABA) and ethylene treatments. Over-expression of TaCIPK29 in tobacco resulted in increased salt tolerance, which was demonstrated by higher germination rates, longer root lengths and better growth status of transgenic tobacco plants compared to controls when both were treated with salt stress. Physiological measurements indicated that transgenic tobacco seedlings retained high K(+)/Na(+) ratios and Ca(2+) content by up-regulating some transporter genes expression and also possessed lower H2O2 levels and reduced membrane injury by increasing the expression and activities of catalase (CAT) and peroxidase (POD) under salt stress. Moreover, transgenic lines conferred tolerance to oxidative stress by increasing the activity and expression of CAT. Finally, TaCIPK29 was located throughout cells and it preferentially interacted with TaCBL2, TaCBL3, NtCBL2, NtCBL3 and NtCAT1. Taken together, our results showed that TaCIPK29 functions as a positive factor under salt stress and is involved in regulating cations and reactive oxygen species (ROS) homeostasis.
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Affiliation(s)
- Xiaomin Deng
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Wei Hu
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Shuya Wei
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Shiyi Zhou
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Fan Zhang
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Jiapeng Han
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Lihong Chen
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Yin Li
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Jialu Feng
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Bin Fang
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Qingchen Luo
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Shasha Li
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Yunyi Liu
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Guangxiao Yang
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
| | - Guangyuan He
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics MoE, College of Life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, China
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14
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Li Y, Li LL, Fan RC, Peng CC, Sun HL, Zhu SY, Wang XF, Zhang LY, Zhang DP. Arabidopsis sucrose transporter SUT4 interacts with cytochrome b5-2 to regulate seed germination in response to sucrose and glucose. MOLECULAR PLANT 2012; 5:1029-41. [PMID: 22311778 DOI: 10.1093/mp/sss001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
It remains unknown whether a sucrose transporter mediates sugar signaling. Here, we report that the Arabidopsis (Arabidopsis thaliana) sucrose transporter SUT4 interacts with five members of the Arabidopsis cytochrome b5 (Cyb5) family, and sucrose represses the interaction between SUT4 and a Cyb5 member Cyb5-2/A. We observed that down-regulation of SUT4 and three cytochrome b5 members (Cyb5-2, Cyb5-4, and Cyb5-6) confers the sucrose- and glucose-insensitive phenotypes in the sucrose/glucose-induced inhibition of seed germination. The sut4 cyb5-2 double mutant displays slightly stronger sucrose/glucose-insensitive phenotypes than either the sut4 or cyb5-2 single mutant. We showed that the SUT4/Cyb5-2-mediated signaling in the sucrose/glucose-induced inhibition of seed germination does not require ABA or the currently known ABI2/ABI4/ABI5-mediated signaling pathway(s). These data provide evidence that the sucrose transporter SUT4 interacts with Cyb5 to positively mediate sucrose and glucose signaling in the sucrose/glucose-induced inhibition of seed germination.
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Affiliation(s)
- Yan Li
- College of Biological Sciences, China Agricultural University, Beijing 100094, China
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15
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Kulik A, Wawer I, Krzywińska E, Bucholc M, Dobrowolska G. SnRK2 protein kinases--key regulators of plant response to abiotic stresses. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2011; 15:859-72. [PMID: 22136638 DOI: 10.1089/omi.2011.0091] [Citation(s) in RCA: 256] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The SnRK2 family members are plant-specific serine/threonine kinases involved in plant response to abiotic stresses and abscisic acid (ABA)-dependent plant development. SnRK2s have been classed into three groups; group 1 comprises kinases not activated by ABA, group 2 comprises kinases not activated or activated very weakly by ABA, and group 3 comprises kinases strongly activated by ABA. So far, the ABA-dependent kinases belonging to group 3 have been studied most thoroughly. They are considered major regulators of plant response to ABA. The regulation of the plant response to ABA via SnRK2s pathways occurs by direct phosphorylation of various downstream targets, for example, SLAC1, KAT1, AtRbohF, and transcription factors required for the expression of numerous stress response genes. Members of group 2 share some cellular functions with group 3 kinases; however, their contribution to ABA-related responses is not clear. There are strong indications that they are positive regulators of plant responses to water deficit. Most probably they complement the ABA-dependent kinases in plant defense against environmental stress. So far, data concerning the physiological role of ABA-independent SnRK2s are very limited; it is to be expected they will be studied extensively in the nearest future.
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Affiliation(s)
- Anna Kulik
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
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16
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Piattoni CV, Bustos DM, Guerrero SA, Iglesias AÁ. Nonphosphorylating glyceraldehyde-3-phosphate dehydrogenase is phosphorylated in wheat endosperm at serine-404 by an SNF1-related protein kinase allosterically inhibited by ribose-5-phosphate. PLANT PHYSIOLOGY 2011; 156:1337-50. [PMID: 21546456 PMCID: PMC3135918 DOI: 10.1104/pp.111.177261] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Accepted: 05/02/2011] [Indexed: 05/17/2023]
Abstract
Nonphosphorylating glyceraldehyde-3-phosphate dehydrogenase (np-Ga3PDHase) is a cytosolic unconventional glycolytic enzyme of plant cells regulated by phosphorylation in heterotrophic tissues. After interaction with 14-3-3 proteins, the phosphorylated enzyme becomes less active and more sensitive to regulation by adenylates and inorganic pyrophosphate. Here, we acknowledge that in wheat (Triticum aestivum), np-Ga3PDHase is specifically phosphorylated by the SnRK (SNF1-related) protein kinase family. Interestingly, only the kinase present in heterotrophic tissues (endosperm and shoots, but not in leaves) was found active. The specific SnRK partially purified from endosperm exhibited a requirement for Mg(2+) or Mn(2+) (being Ca(2+) independent), having a molecular mass of approximately 200 kD. The kinase also phosphorylated standard peptides SAMS, AMARA, and SP46, as well as endogenous sucrose synthase, results suggesting that it could be a member of the SnRK1 subfamily. Concurrently, the partially purified wheat SnRK was recognized by antibodies raised against a peptide conserved between SnRK1s from sorghum (Sorghum bicolor) and maize (Zea mays) developing seeds. The wheat kinase was allosterically inhibited by ribose-5-phosphate and, to a lesser extent, by fructose-1,6-bisphosphate and 3-phosphoglycerate, while glucose-6-phosphate (the main effector of spinach [Spinacia oleracea] leaves, SnRK1) and trehalose-6-phosphate produced little or no effect. Results support a distinctive allosteric regulation of SnRK1 present in photosynthetic or heterotrophic plant tissues. After in silico analysis, we constructed two np-Ga3PDHase mutants, S404A and S447A, identifying serine-404 as the target of phosphorylation. Results suggest that both np-Ga3PDHase and the specific kinase could be under control, critically affecting the metabolic scenario involving carbohydrates and reducing power partition and storage in heterotrophic plant cells.
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Affiliation(s)
| | | | | | - Alberto Álvaro Iglesias
- Instituto de Agrobiotecnología del Litoral (Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad Nacional del Litoral), Facultad de Bioquímica y Ciencias Biológicas, Paraje “El Pozo,” S3000ZAA Santa Fe, Argentina (C.V.P., S.A.G., A.A.I.); Instituto Tecnológico de Chascomús (Consejo Nacional de Investigaciones Científicas y Técnicas), 7130 Chascomus, Argentina (D.M.B.)
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17
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Skylar A, Wu X. Regulation of meristem size by cytokinin signaling. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2011; 53:446-54. [PMID: 21554538 DOI: 10.1111/j.1744-7909.2011.01045.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The plant meristems possess unique features that involve maintaining the stem cell populations while providing cells for continued development. Although both the primary shoot apical meristem (SAM) and the root apical meristem (RAM) are specified during embryogenesis, post-embryonic tissue proliferation is required for their full establishment and maintenance throughout a plants' life. The phytohormone cytokinin (CK) interacts with other systemic signals and is a key regulator of meristem size and functions. The SAM and the RAM respond to CK stimulations in different manners: CK promotes tissue proliferation in the SAM through pathways dominated by homeobox transcription factors, including the class I KNOX genes, STIP, and WUS; and curiously, it favors proliferation at low levels and differentiation at a slightly higher concentration in the RAM instead. Here we review the current understanding of the molecular mechanisms underlying CK actions in regulating meristematic tissue proliferation.
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Affiliation(s)
- Anna Skylar
- Molecular and Computational Biology, University of Southern California, Los Angeles, USA
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18
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Tominaga M, Harada A, Kinoshita T, Shimazaki KI. Biochemical Characterization of Calcineurin B-Like-Interacting Protein Kinase in Vicia Guard Cells. ACTA ACUST UNITED AC 2010; 51:408-21. [DOI: 10.1093/pcp/pcq006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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19
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Radchuk R, Emery RJN, Weier D, Vigeolas H, Geigenberger P, Lunn JE, Feil R, Weschke W, Weber H. Sucrose non-fermenting kinase 1 (SnRK1) coordinates metabolic and hormonal signals during pea cotyledon growth and differentiation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 61:324-38. [PMID: 19845880 DOI: 10.1111/j.1365-313x.2009.04057.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Seed development passes through developmental phases such as cell division, differentiation and maturation: each have specific metabolic demands. The ubiquitous sucrose non-fermenting-like kinase (SnRK1) coordinates and adjusts physiological and metabolic demands with growth. In protoplast assays sucrose deprivation and hormone supplementation, such as with auxin and abscisic acid (ABA), stimulate SnRK1-promoter activity. This indicates regulation by nutrients: hormonal crosstalk under conditions of nutrient demand and cell proliferation. SnRK1-repressed pea (Pisum sativum) embryos show lower cytokinin levels and deregulation of cotyledonary establishment and growth, together with downregulated gene expression related to cell proliferation, meristem maintenance and differentiation, leaf formation, and polarity. This suggests that at early stages of seed development SnRK1 regulates coordinated cotyledon emergence and growth via cytokinin-mediated auxin transport and/or distribution. Decreased ABA levels and reduced gene expression, involved in ABA-mediated seed maturation and response to sugars, indicate that SnRK1 is required for ABA synthesis and/or signal transduction at an early stage. Metabolic profiling of SnRK1-repressed embryos revealed lower levels of most organic and amino acids. In contrast, levels of sugars and glycolytic intermediates were higher or unchanged, indicating decreased carbon partitioning into subsequent pathways such as the tricarbonic acid cycle and amino acid biosynthesis. It is hypothesized that SnRK1 mediates the responses to sugar signals required for early cotyledon establishment and patterning. As a result, later maturation and storage activity are strongly impaired. Changes observed in SnRK1-repressed pea seeds provide a framework for how SnRK1 communicates nutrient and hormonal signals from auxins, cytokinins and ABA to control metabolism and development.
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Affiliation(s)
- Ruslana Radchuk
- Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK), Corrensstrasse 3, D-06466 Gatersleben, Germany
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20
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Hamada S, Seiki Y, Watanabe K, Ozeki T, Matsui H, Ito H. Expression and interaction of the CBLs and CIPKs from immature seeds of kidney bean (Phaseolus vulgaris L.). PHYTOCHEMISTRY 2009; 70:501-507. [PMID: 19278694 DOI: 10.1016/j.phytochem.2009.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Revised: 01/22/2009] [Accepted: 02/03/2009] [Indexed: 05/27/2023]
Abstract
Protein phosphorylation plays a key regulatory role in a variety of cellular processes. To better understand the function of protein phosphorylation in seed maturation, a PCR-based cloning method was employed and five cDNA clones (pvcipk1-5) for protein kinases were isolated from a cDNA library prepared from immature seeds of kidney bean (Phaseolus vulgaris L.). The deduced amino acid sequences showed that the five protein kinases (PvCIPK1-5) are members of the sucrose non-fermenting 1-related protein kinase type 3 (SnRK3) family, which interacts with calcineurin B-like proteins (CBLs). Two cDNA clones (pvcbl1 and 2) for CBLs were further isolated from the cDNA library. The predicted primary sequences of the proteins (PvCBL1 and 2) displayed significant identity (more than 90%) with those of other plant CBLs. Semi-quantitative RT-PCR analysis showed that the isolated genes, except pvcbl1, are expressed in leaves and early maturing seeds, whereas pvcbl1 is constitutively expressed during seed development. Yeast two-hybrid assay indicated that among the five PvCIPKs, only PvCIPK1 interacts with both PvCBL1 and PvCBL2. These results suggest that calcium-dependent protein phosphorylation-signaling via CBL-CIPK complexes occurs during seed development.
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Affiliation(s)
- Shigeki Hamada
- Division of Applied Bioscience, Hokkaido University, Kita-9, Nishi-9, Kita-ku, Sapporo 060-8589, Japan
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Abstract
In higher plants, light is crucial for regulation of nitrate uptake, translocation and assimilation into organic compounds. Part of this metabolism is tightly coupled to photosynthesis because the enzymes involved, nitrite reductase and glutamate synthase, are localized to the chloroplasts and receive reducing power from photosynthetic electron transport. However, important enzymes in nitrate acquisition and reduction are localized to cellular compartments other than chloroplasts and are also up-regulated by light, i.e. transporters in cell and organellar membranes and nitrate reductase in the cytosol. This review describes the different light-dependent signalling cascades regulating nitrate metabolism at the transcriptional as well as post-transcriptional level, and how reactions in different compartments of the cell are co-ordinated. Essential players in this network are phytochrome and HY5 (long hypocotyls 5)/HYH (HY5 homologue)-dependent signalling pathways, the energy-related AMPK (AMP-activated protein kinase) protein kinase homologue SNRK1 (sucrose non-fermenting kinase 1-related kinase), chloroplastic thioredoxins and the prokaryotically originated PII protein. A complex light-dependent network of regulation emerges, which appears to be necessary for optimal nitrogen assimilation and for avoiding the accumulation of toxic intermediates and side products, such as nitrite and reactive oxygen compounds.
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Shukla V, Mattoo AK. Sucrose non-fermenting 1-related protein kinase 2 (SnRK2): a family of protein kinases involved in hyperosmotic stress signaling. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2008; 14:91-100. [PMID: 23572876 PMCID: PMC3550663 DOI: 10.1007/s12298-008-0008-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Our understanding of plant adaptation to abiotic stresses, which include drought, salinity, non-optimal temperatures and poor soil nutrition, is limited, although significant strides have been made in identifying some of the gene players and signaling partners. Several protein kinases get activated in plants in response to osmotic stress and the stress hormone abscisic acid (ABA). Among these is a superfamily of sucrose non-fermenting protein kinase genes (SnRK2). This review focuses on the developments related to the activity, substrates, interacting proteins and gene regulation of SnRK2 gene family members. Reversible phosphorylation as a crucial regulatory mechanism turns out to be a rule rather than an exception in plant responses to abiotic stress. Nine out of thirteen bZIP transcription factors (ABI5/ABF/AREB family) share the recognition motif, R-Q-X-S/T, suggesting that likely SnRK2 kinases have a major role in regulating gene expression during hyperosmotic stress.
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Affiliation(s)
- Vijaya Shukla
- />Sustainable Agricultural Systems Laboratory, USDA-ARS, The Henry A. Wallace Beltsville Agricultural Research Center, Building 001, Beltsville, MD 20705-2350 USA
- />Center for Biosystems Research, University of Maryland Biotechnology Institute, College Park, MD 20742 USA
| | - Autar K. Mattoo
- />Sustainable Agricultural Systems Laboratory, USDA-ARS, The Henry A. Wallace Beltsville Agricultural Research Center, Building 001, Beltsville, MD 20705-2350 USA
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Ruuska SA, Lewis DC, Kennedy G, Furbank RT, Jenkins CLD, Tabe LM. Large scale transcriptome analysis of the effects of nitrogen nutrition on accumulation of stem carbohydrate reserves in reproductive stage wheat. PLANT MOLECULAR BIOLOGY 2008; 66:15-32. [PMID: 17934784 DOI: 10.1007/s11103-007-9249-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Accepted: 09/28/2007] [Indexed: 05/04/2023]
Abstract
We investigated the molecular basis of the long-term adaptation to nitrogen (N) limitation of wheat plants grown in a simulated crop canopy, with a focus on the stage when carbon (C) reserves are accumulated in stems for later remobilization to grain. A cDNA microarray representing approximately 36,000 unique sequences was used to compare gene expression in a number of above-ground organs at anthesis. Fructan accumulation in stems was accompanied by elevated transcripts for a suite of fructosyltransferases (FTs) and for a fructan 6-exohydrolase (6-FEH) in the low N compared to high N stems. Clustering analysis identified a grouping that included several FTs and a number of genes thought to be involved in regulation of storage C metabolism or senescence in other systems. Transcripts for three FTs and for 6-FEH increased, while transcripts for 1-FEH decreased, in sucrose-fed wheat stems compared to controls. The opposite trends were seen for these transcripts in wheat stems fed ABA. Of the putative regulators, only transcripts for the WPK4 kinase increased in response to sucrose, suggesting a role for this kinase in C storage metabolism in the reproductive wheat stems grown in low N. This work represents the first large-scale transcriptome study of responses to the most common nutrient limitation in one of the world's most economically important crops.
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Affiliation(s)
- Sari A Ruuska
- Graingene, CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia
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Guidetti-Gonzalez S, Ragassi CF, Carrer H. Identification of protein kinase SNF1 in CitEST. Genet Mol Biol 2007. [DOI: 10.1590/s1415-47572007000500015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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25
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Boscariol-Camargo RL, Berger IJ, Souza AA, Amaral AMD, Carlos EF, Freitas-Astúa J, Takita MA, Targon MLP, Medina CL, Reis MS, Machado MA. In silico analysis of ESTs from roots of Rangpur lime (Citrus limonia Osbeck) under water stress. Genet Mol Biol 2007. [DOI: 10.1590/s1415-47572007000500019] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
| | | | | | - Alexandre M. do Amaral
- Instituto Agronômico de Campinas, Brazil; EMBRAPA Recursos Genéticos e Biotecnologia, Brazil
| | | | - Juliana Freitas-Astúa
- Instituto Agronômico de Campinas, Brazil; EMBRAPA Mandioca e Fruticultura Tropical, Brazil
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26
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Laxmi A, Paul LK, Raychaudhuri A, Peters JL, Khurana JP. Arabidopsis cytokinin-resistant mutant, cnr1, displays altered auxin responses and sugar sensitivity. PLANT MOLECULAR BIOLOGY 2006; 62:409-25. [PMID: 16915515 DOI: 10.1007/s11103-006-9032-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Accepted: 06/08/2006] [Indexed: 05/11/2023]
Abstract
Based upon the phenotype of young, dark-grown seedlings, a cytokinin-resistant mutant, cnr1, has been isolated, which displays altered cytokinin- and auxin-induced responses. The mutant seedlings possess short hypocotyls and open apical hooks (in dark), and display agravitropism, hyponastic cotyledons, reduced shoot growth, compact rosettes and short roots with increased adventitious branching and reduced number of root hairs. A number of these features invariably depend upon auxin/cytokinin ratio but the cnr1 mutant retains normal sensitivity towards auxin as well as auxin polar transport inhibitor, TIBA, although upregulation of primary auxin-responsive Aux/IAA genes is reduced. The mutant shows resistance towards cytokinin in hypocotyl/root growth inhibition assays, displays reduced regeneration in tissue cultures (cytokinin response) and decreased sensitivity to cytokinin for anthocyanin accumulation. It is thus conceivable that due to reduced sensitivity to cytokinin, the cnr1 mutant also shows altered auxin response. Surprisingly, the mutant retains normal sensitivity to cytokinin for induction of primary response genes, the type-A Arabidopsis response regulators, although the basal level of their expression was considerably reduced as compared to the wild-type. The zeatin and zeatin riboside levels, as estimated by HPLC, and the cytokinin oxidase activity were comparable in the cnr1 mutant and the wild-type. The hypersensitivity to red light (in hypocotyl growth inhibition assay), partial photomorphogenesis in dark, and hypersensitivity to sugars, are some other features displayed by the cnr1 mutant. The lesion in the cnr1 mutant has been mapped to the top of chromosome 1 where no other previously known cytokinin-resistant mutant has been mapped, indicating that the cnr1 mutant defines a novel locus involved in hormone, light and sugar signalling.
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Affiliation(s)
- Ashverya Laxmi
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110021, India
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27
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Kelner A, Pekala I, Kaczanowski S, Muszynska G, Hardie DG, Dobrowolska G. Biochemical characterization of the tobacco 42-kD protein kinase activated by osmotic stress. PLANT PHYSIOLOGY 2004; 136:3255-65. [PMID: 15466234 PMCID: PMC523384 DOI: 10.1104/pp.104.046151] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2004] [Revised: 07/12/2004] [Accepted: 07/12/2004] [Indexed: 05/19/2023]
Abstract
In tobacco (Nicotiana tabacum), hyperosmotic stress induces rapid activation of a 42-kD protein kinase, referred to as Nicotiana tabacum osmotic stress-activated protein kinase (NtOSAK). cDNA encoding the kinase was cloned and, based on the predicted amino acid sequence, the enzyme was assigned to the SNF1-related protein kinase type 2 (SnRK2) family. The identity of the enzyme was confirmed by immunoprecipitation of the active kinase from tobacco cells subjected to osmotic stress using antibodies raised against a peptide corresponding to the C-terminal sequence of the kinase predicted from the cloned cDNA. A detailed biochemical characterization of NtOSAK purified from stressed tobacco cells was performed. Our results show that NtOSAK is a calcium-independent Ser/Thr protein kinase. The sequence of putative phosphorylation sites recognized by NtOSAK, predicted by the computer program PREDIKIN, resembled the substrate consensus sequence defined for animal and yeast (Saccharomyces cerevisiae) AMPK/SNF1 kinases. Our experimental data confirmed these results, as various targets for AMPK/SNF1 kinases were also efficiently phosphorylated by NtOSAK. A range of protein kinase inhibitors was tested as potential modulators of NtOSAK, but only staurosporine, a rather nonspecific protein kinase inhibitor, was found to abolish the enzyme activity. In phosphorylation reactions, NtOSAK exhibited a preference for Mg(2+) over Mn(2+) ions and an inability to use GTP instead of ATP as a phosphate donor. The enzyme activity was not modulated by 5'-AMP. To our knowledge, these results represent the first detailed biochemical characterization of a kinase of the SnRK2 family.
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Affiliation(s)
- Anna Kelner
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
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28
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Kim KN, Lee JS, Han H, Choi SA, Go SJ, Yoon IS. Isolation and characterization of a novel rice Ca2+-regulated protein kinase gene involved in responses to diverse signals including cold, light, cytokinins, sugars and salts. PLANT MOLECULAR BIOLOGY 2003; 52:1191-202. [PMID: 14682618 DOI: 10.1023/b:plan.0000004330.62660.a2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We have isolated a cold-inducible gene (designated OsCK1) from Oryza sativa by a differential cDNA screening technique. Sequence analysis indicated that the open reading frame of the OsCK1 gene consists of 1350 bp encoding 449 amino acid residues, which is very similar to a family of calcineurin B-like protein (CBL)-interacting protein kinases (CIPKs) or salt overly sensitive 2 (SOS2)-like protein kinases (PKS) in Arabidopsis. CIPKs/PKS are a group of Ser/Thr protein kinases associated with the AtCBL/SOS3-like calcium-binding proteins (SCaBP). OsCK1 actually interacts with AtCBL3 through the C-terminal region in a yeast two-hybrid system, suggesting that OsCK1 is probably a rice orthologue of one of the CIPK/PKS members. Expression of the OsCK1 gene was detected mainly in the shoots and highly inducible by diverse signals such as cold, light, salt, sugar and cytokinins. In addition, calcium increased the OsCK1 transcript level, whereas a calcium ionophore, A23187, partially abolished stimulus-induced expressions. OsCK1 phosphorylated itself and a generic substrate, myelin basic protein, in the preference of Mn2+. Deletion of the C-terminal region from OsCK1 significantly decreased autophosphorylation activity without affecting the ability for substrate phosphorylation. These findings suggest that the CBL/CIPK or SCaBP/PKS signaling pathways recently found in Arabidopsis may also exist in rice and function in cold response in which calcium signal serves as a second messenger.
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Affiliation(s)
- Kyung-Nam Kim
- Department of Molecular Physiology, National Institute of Agricultural Biotechnology, Suweon 441-707, Korea
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29
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Yu LX, Setter TL. Comparative transcriptional profiling of placenta and endosperm in developing maize kernels in response to water deficit. PLANT PHYSIOLOGY 2003; 131:568-82. [PMID: 12586881 PMCID: PMC166833 DOI: 10.1104/pp.014365] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2002] [Revised: 10/07/2002] [Accepted: 11/06/2002] [Indexed: 05/20/2023]
Abstract
The early post-pollination phase of maize (Zea mays) development is particularly sensitive to water deficit stress. Using cDNA microarray, we studied transcriptional profiles of endosperm and placenta/pedicel tissues in developing maize kernels under water stress. At 9 d after pollination (DAP), placenta/pedicel and endosperm differed considerably in their transcriptional responses. In placenta/pedicel, 79 genes were significantly affected by stress and of these 89% were up-regulated, whereas in endosperm, 56 genes were significantly affected and 82% of these were down-regulated. Only nine of the stress-regulated genes were in common between these tissues. Hierarchical cluster analysis indicated that different sets of genes were regulated in the two tissues. After rewatering at 9 DAP, profiles at 12 DAP suggested that two regulons exist, one for genes responding specifically to concurrent imposition of stress, and another for genes remaining affected after transient stress. In placenta, genes encoding recognized stress tolerance proteins, including heat shock proteins, chaperonins, and major intrinsic proteins, were the largest class of genes regulated, all of which were up-regulated. In contrast, in endosperm, genes in the cell division and growth category represented a large class of down-regulated genes. Several cell wall-degrading enzymes were expressed at lower levels than in controls, suggesting that stress delayed normal advance to programmed cell death in the central endosperm. We suggest that the responsiveness of placenta to whole-plant stress factors (water potential, abscisic acid, and sugar flux) and of endosperm to indirect factors may play key roles in determining the threshold for kernel abortion.
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Affiliation(s)
- Long-Xi Yu
- Department of Crop and Soil Sciences, Cornell University, Ithaca, New York 14853, USA
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30
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Schäfer S, Schmülling T. The CRK1 receptor-like kinase gene of tobacco is negatively regulated by cytokinin. PLANT MOLECULAR BIOLOGY 2002; 50:155-66. [PMID: 12175009 DOI: 10.1023/a:1016087908746] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This report describes a novel receptor-like kinase gene of tobacco (Nicotiana tabacum L.) that, in cell culture, is rapidly regulated by very low concentrations of cytokinin. The steady-state transcript level of the CYTOKONIN-REGULATED KINASE 1 gene (CRK1) was strongly reduced 30 min after cytokinin treatment. At higher concentrations abscisic acid and auxin induced a similar response. None of the other plant hormones tested elicited this response. Further analyses of the cytokinin-dependentregulation showed that the reduction of transcript was transient, and the duration of the recovery phase was dependent on the hormone concentration. CRKI is not a primary response gene as the simultaneous addition of cycloheximide inhibits its regulation by cytokinin. Inhibitor studies revealed that a protein phosphatase is likely involved in signalling processes upstream of CRK1. CRKI is expressed at low levels in the leaves, stem and roots of tobacco. It is predicted that the CRK1 protein is located in the plasma membrane. It has in its N-terminal putative receptor sequence a signal peptide, a serine- and a proline-rich region, a six repeat motif similar to the CRINKLY4 protein of Zea mays and several regions homologous to purine-binding motifs. A single transmembrane domain is followed by a highly conserved intracellular Ser/Thr kinase domain. Therefore, CRKI is a novel type of class I plant receptor kinase. We hypothesize that CRKI is involved in an early step of hormone signalling and that transcript down-regulation reflects a desensitization step in reaction to the signalling molecule.
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MESH Headings
- Base Sequence
- Cloning, Molecular
- Cytokinins/pharmacology
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- Dose-Response Relationship, Drug
- Gene Expression Regulation, Enzymologic/drug effects
- Gene Expression Regulation, Plant/drug effects
- Molecular Sequence Data
- Plant Growth Regulators/pharmacology
- Protein Kinases/genetics
- RNA, Plant/drug effects
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Nicotiana/enzymology
- Nicotiana/genetics
- Transcription, Genetic
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Affiliation(s)
- Silke Schäfer
- Universität Tübingen, Centre for Plant Molecular Biology (ZMPB), Allgemeine Genetik, Germany
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31
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Møller SG, Ingles PJ, Whitelam GC. The cell biology of phytochrome signalling. THE NEW PHYTOLOGIST 2002; 154:553-590. [PMID: 33873456 DOI: 10.1046/j.1469-8137.2002.00419.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Phytochrome signal transduction has in the past often been viewed as being a nonspatially separated linear chain of events. However, through a combination of molecular, genetic and cell biological approaches, it is becoming increasingly evident that phytochrome signalling constitutes a highly ordered multidimensional network of events. The discovery that some phytochromes and signalling intermediates show light-dependent nucleo-cytoplasmic partitioning has not only led to the suggestion that early signalling events take place in the nucleus, but also that subcellular localization patterns most probably represent an important signalling control point. Moreover, detailed characterization of signalling intermediates has demonstrated that various branches of the signalling network are spatially separated and take place in different cellular compartments including the nucleus, cytosol, and chloroplasts. In addition, proteasome-mediated degradation of signalling intermediates most probably act in concert with subcellular partitioning events as an integrated checkpoint. An emerging view from this is that phytochrome signalling is separated into several subcellular organelles and that these are interconnected in order to execute accurate responses to changes in the light environment. By integrating the available data, both at the cellular and subcellular level, we should be able to construct a solid foundation for further dissection of phytochrome signal transduction in plants. Contents Summary 553 I. Introduction 554 II. Nucleus vs cytoplasm 556 III. The nucleus 562 IV. The cytoplasm 571 V. Interactions with other signalling pathways 577 VI. Conclusions and the future 582 Acknowledgements 583 References 583.
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Affiliation(s)
- Simon G Møller
- Department of Biology, University of Leicester, University Road, Leicester, LE1 7RH, UK
| | - Patricia J Ingles
- Department of Biology, University of Leicester, University Road, Leicester, LE1 7RH, UK
| | - Garry C Whitelam
- Department of Biology, University of Leicester, University Road, Leicester, LE1 7RH, UK
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32
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Gong D, Gong Z, Guo Y, Zhu JK. Expression, activation, and biochemical properties of a novel Arabidopsis protein kinase. PLANT PHYSIOLOGY 2002; 129:225-34. [PMID: 12011353 PMCID: PMC155886 DOI: 10.1104/pp.010776] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2001] [Revised: 12/11/2001] [Accepted: 01/15/2002] [Indexed: 05/17/2023]
Abstract
An Arabidopsis SOS2 (salt overly sensitive 2)-like protein kinase gene, PKS6, was expressed in leaves, stems, and siliques, but not detectable in roots of adult plants; its expression in young seedlings was up-regulated by abscisic acid. To determine the biochemical properties of the PKS6 protein, we expressed the PKS6 coding sequence as a glutathione S-transferase fusion protein in Escherichia coli. The bacterially expressed glutathione S-transferase-PKS6 fusion protein was inactive in substrate phosphorylation. We have constructed constitutively active forms of PKS6 by either a deletion of its putative auto-inhibitory FISL motif (i.e. PKS6deltaF) or a substitution of threonine-178 with aspartic acid within the putative activation loop. We found that PKS6deltaF exhibited a strong preference for Mn2+ over Mg2+ as a divalent cation cofactor for kinase activity. PKS6DeltaF displayed substrate specificity against three different peptide substrates and had an optimal pH of approximately 7.5 and temperature optimum of 30 degrees C. The apparent Km values for ATP and the preferred peptide substrate p3 of PKS6deltaF were determined to be 1.7 and 28.5 microM, respectively. These results provide significant insights into the regulation and biochemical properties of the protein kinase PKS6. In addition, the constitutively active, gain-of-function kinase mutants will be invaluable for future determination of the in planta function of PKS6.
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Affiliation(s)
- Deming Gong
- Department of Plant Sciences, University of Arizona, Tucson, Arizona 85721, USA
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33
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Rolland F, Moore B, Sheen J. Sugar sensing and signaling in plants. THE PLANT CELL 2002; 14 Suppl:S185-205. [PMID: 12045277 PMCID: PMC151255 DOI: 10.1105/tpc.010455] [Citation(s) in RCA: 367] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2001] [Accepted: 02/20/2002] [Indexed: 05/18/2023]
Affiliation(s)
| | | | - Jen Sheen
- To whom correspondence should be addressed. E-mail ; fax 617-726-6893
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34
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Koizumi N, Martinez IM, Kimata Y, Kohno K, Sano H, Chrispeels MJ. Molecular characterization of two Arabidopsis Ire1 homologs, endoplasmic reticulum-located transmembrane protein kinases. PLANT PHYSIOLOGY 2001; 127:949-962. [PMID: 11706177 DOI: 10.1104/pp.010636] [Citation(s) in RCA: 159] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
A major response of eukaryotic cells to the presence of unfolded proteins in the lumen of the endoplasmic reticulum (ER) is to activate genes that encode ER-located molecular chaperones, such as the binding protein. This response, called the unfolded protein response, requires the transduction of a signal from the ER to the nucleus. In yeast (Saccharomyces cerevisiae) and mammalian cells, an ER-located transmembrane receptor protein kinase/ribonuclease called Ire1, with a sensor domain in the lumen of the ER, is the first component of this pathway. Here, we report the cloning and derived amino acid sequences of AtIre1-1 and AtIre1-2, two Arabidopsis homologs of Ire1. The two proteins are located in the perinuclear ER (based on heterologous expression of fusions with green fluorescent protein). The expression patterns of the two genes (using beta-glucuronidase fusions) are nearly nonoverlapping. We also demonstrate functional complementation of the sensor domains of the two proteins in yeast and show that the Ire1-2 protein is capable of autotransphosphorylation. These and other findings are discussed in relation to the involvement of these genes in unfolded protein response signaling in plants.
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Affiliation(s)
- N Koizumi
- Division of Biology, University of California San Diego, La Jolla, CA 92039-0116, USA
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35
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Kim JH, Kim WT, Kang BG. IAA and N(6)-benzyladenine inhibit ethylene-regulated expression of ACC oxidase and ACC synthase genes in mungbean hypocotyls. PLANT & CELL PHYSIOLOGY 2001; 42:1056-61. [PMID: 11673620 DOI: 10.1093/pcp/pce133] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Regulation of expression of 1-aminocyclopropane-1-carboxylate (ACC) oxidase (VR-ACO1) and ACC synthase (VR-ACS1) genes by ethylene, indole-3-acetic acid (IAA), and N(6)-benzyladenine (BA), was investigated in mungbean hypocotyl tissues. Exogenous ethylene markedly increased transcript level of VR-ACO1 and reduced that of VR-ACS1, whereas aminooxyacetic acid (AOA), an inhibitor of ethylene biosynthesis, decreased the level of VR-ACO1 mRNA and increased that of VR-ACS1, indicating that expression of VR-ACO1 and VR-ACS1 genes are under positive and negative feedback control by ethylene, respectively. However, IAA treatment reduced the level of VR-ACO1 transcripts and increased that of VR-ACS1, although the hormone greatly induced ethylene production. We have demonstrated that, in a system that separates the effect of IAA proper from the effect of IAA-induced ethylene, the amount of IAA-induced ethylene was enough to cause accumulation of VR-ACO1 mRNA and decrease of VR-ACS1 mRNA. We have also shown that the responsiveness of VR-ACO1 and VR-ACS1 to exogenous ethylene was greatly reduced in the presence of IAA. In addition, BA abolished ethylene responsiveness with respect to expression of VR-ACO1 and VR-ACS1. Based on these results, we suggest that IAA and BA inhibit ethylene action, resulting in suppression of VR-ACO1 expression and induction of VR-ACS1 expression.
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Affiliation(s)
- J H Kim
- Department of Biology, Yonsei University, Seoul 120-749, The Republic of Korea.
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36
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Ogawa M, Herai Y, Koizumi N, Kusano T, Sano H. 7-Methylxanthine methyltransferase of coffee plants. Gene isolation and enzymatic properties. J Biol Chem 2001; 276:8213-8. [PMID: 11108716 DOI: 10.1074/jbc.m009480200] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Caffeine is synthesized through sequential three-step methylation of xanthine derivatives at positions 7-N, 3-N, and 1-N. However, controversy exists as to the number and properties of the methyltransferases involved. Using primers designed on the basis of conserved amino acid regions of tea caffeine synthase and Arabidopsis hypothetical proteins, a particular DNA fragment was amplified from an mRNA population of coffee plants. Subsequently, this fragment was used as a probe, and four independent clones were isolated from a cDNA library derived from coffee young leaves. Upon expression in Escherichia coli, one of them was found to encode a protein possessing 7-methylxanthine methyltransferase activity and was designated as CaMXMT. It consists of 378 amino acids with a relative molecular mass of 42.7 kDa and shows similarity to tea caffeine synthase (35.8%) and salicylic acid methyltransferase (34.1%). The bacterially expressed protein exhibited an optimal pH for activity ranging between 7 and 9 and methylated almost exclusively 7-methylxanthine with low activity toward paraxanthine, indicating a strict substrate specificity regarding the 3-N position of the purine ring. K(m) values were estimated to be 50 and 12 microM for 7-methylxanthine and S-adenosyl-l-methionine, respectively. Transcripts of CaMXMT could be shown to accumulate in young leaves and stems containing buds, and green fluorescent protein fusion protein assays indicated localization in cytoplasmic fractions. The results suggest that, in coffee plants, caffeine is synthesized through three independent methylation steps from xanthosine, in which CaMXMT catalyzes the second step to produce theobromine.
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Affiliation(s)
- M Ogawa
- Research and Education Center for Genetic Information, Nara Institute of Science and Technology, Nara 630-0101, Japan
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37
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Albrecht V, Ritz O, Linder S, Harter K, Kudla J. The NAF domain defines a novel protein-protein interaction module conserved in Ca2+-regulated kinases. EMBO J 2001; 20:1051-63. [PMID: 11230129 PMCID: PMC145464 DOI: 10.1093/emboj/20.5.1051] [Citation(s) in RCA: 247] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The Arabidopsis calcineurin B-like calcium sensor proteins (AtCBLs) interact with a group of serine-threonine protein kinases (AtCIPKs) in a calcium-dependent manner. Here we identify a 24 amino acid domain (NAF domain) unique to these kinases as being required and sufficient for interaction with all known AtCBLs. Mutation of conserved residues either abolished or significantly diminished the affinity of AtCIPK1 for AtCBL2. Comprehensive two-hybrid screens with various AtCBLs identified 15 CIPKs as potential targets of CBL proteins. Database analyses revealed additional kinases from Arabidopsis and other plant species harbouring the NAF interaction module. Several of these kinases have been implicated in various signalling pathways mediating responses to stress, hormones and environmental cues. Full-length CIPKs show preferential interaction with distinct CBLs in yeast and in vitro assays. Our findings suggest differential interaction affinity as one of the mechanisms generating the temporal and spatial specificity of calcium signals within plant cells and that different combinations of CBL-CIPK proteins contribute to the complex network that connects various extracellular signals to defined cellular responses.
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Affiliation(s)
| | | | | | - Klaus Harter
- Universität Ulm, Molekulare Botanik, Albert-Einstein-Allee 11, D-89069 Ulm and
Universität Freiburg, Institut für Biologie II, Schänzlestraße 1, D-79104 Freiburg, Germany Corresponding author e-mail:
| | - Jörg Kudla
- Universität Ulm, Molekulare Botanik, Albert-Einstein-Allee 11, D-89069 Ulm and
Universität Freiburg, Institut für Biologie II, Schänzlestraße 1, D-79104 Freiburg, Germany Corresponding author e-mail:
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38
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Adams WW, Demmig-Adams B, Rosenstiel TN, Ebbert V. Dependence of photosynthesis and energy dissipation activity upon growth form and light environment during the winter. PHOTOSYNTHESIS RESEARCH 2001; 67:51-62. [PMID: 16228316 DOI: 10.1023/a:1010688528773] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Two very distinctive responses of photosynthesis to winter conditions have been identified. Mesophytic species that continue to exhibit growth during the winter typically exhibit higher maximal rates of photosynthesis during the winter or when grown at lower temperatures compared to individuals examined during the summer or when grown at warmer temperatures. In contrast, sclerophytic evergreen species growing in sun-exposed sites typically exhibit lower maximal rates of photosynthesis in the winter compared to the summer. On the other hand, shaded individuals of those same sclerophytic evergreen species exhibit similar or higher maximal rates of photosynthesis in the winter compared to the summer. Employment of the xanthophyll cycle in photoprotective energy dissipation exhibits similar characteristics in the two groups of plants (mesophytes and shade leaves of sclerophytic evergreens) that exhibit upregulation of photosynthesis during the winter. In both, zeaxanthin + antheraxanthin (Z + A) are retained and PS II remains primed for energy dissipation only on nights with subfreezing temperatures, and this becomes rapidly reversed upon exposure to increased temperatures. In contrast, Z + A are retained and PS II remains primed for energy dissipation over prolonged periods during the winter in sun leaves of sclerophytic evergreen species, and requires days of warming to become fully reversed. The rapid disengagement of this energy dissipation process in the mesophytes and shade sclerophytes apparently permits a rapid return to efficient photosynthesis and increased activity on warmer days during the winter. This may be associated with a decreasing opportunity for photosynthesis in source leaves relative to the demand for photosynthesis in the plant's sinks. In contrast, the sun-exposed sclerophytes - with a relatively high source to sink ratio - maintain PS II in a state primed for high levels of energy dissipation activity throughout much of the winter. Independent of whether photosynthesis was up- or downregulated, all species under all conditions exhibited higher levels of soluble carbohydrates during the winter compared to the summer. Thus downregulation of photosynthesis and of Photosystem II do not appear to limit carbohydrate accumulation under winter conditions. A possible signal communicating an altered source/sink balance, or that may be influencing the engagement of Z + A in energy dissipation, is phosphorylation of thylakoid proteins such as D1.
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Affiliation(s)
- W W Adams
- Department of Environmental, Population, and Organismic Biology, University of Colorado, Boulder, CO, 80309-0334, USA,
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39
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Mitra D, Johri MM. Enhanced expression of a calcium-dependent protein kinase from the moss Funaria hygrometrica under nutritional starvation. J Biosci 2000; 25:331-8. [PMID: 11120585 DOI: 10.1007/bf02703786] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Among the downstream targets of calcium in plants, calcium-dependent protein kinases (CDPKs) form an interesting class of kinases which are activated by calcium binding. They have been implicated in a diverse array of responses to hormonal and environmental stimuli. In order to dissect the role of CDPKs in the moss Funaria hygrometrica, a polymerase chain reaction (PCR)-based approach was adopted to clone the gene. Using degenerate PCR primers against conserved regions of CDPKs, a 900 bp amplicon was obtained from the genomic DNA of Funaria. Southern hybridization under low stringency conditions indicated the presence of several CDPK related sequences in the Funaria genome. This observation is consistent with reports of multigene families of CDPKs in other plants. The 900 bp fragment was subsequently used to isolate a 2.2 kb partial genomic clone of the CDPK gene from Funaria. The genomic clone encodes an open reading frame (ORF) of 518 amino acids. Interestingly, unlike other CDPK genes from plants, the entire 1.5 kb ORF is not interrupted by introns. The deduced amino acid sequence of the Funaria gene shows extensive homology with CDPKs from higher plants, 73% identity with the Fragaria CDPK and 71% identity with CDPK isoform 7 of Arabidopsis. Phylogenetic analysis revealed that the Funaria CDPK is closer to the CDPKs from higher plants like strawberry and Arabidopsis as compared to those from lower plants such as the liverwort Marchantia, the green alga Chlamydomonas or another moss Tortula. Northern analysis shows enhanced expression of the CDPK transcript within 24-48 h of starvation for nitrogen, phosphorus or sulphur. So far the only other kinase which is known to be induced by nutrient starvation in plants is the wpk 4 which is a snf-1 related kinase (SnRKs). To our knowledge this is the first report that implicates a CDPK in the starvation response.
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Affiliation(s)
- D Mitra
- Department of Biological Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India
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Gibson SI. Plant sugar-response pathways. Part of a complex regulatory web. PLANT PHYSIOLOGY 2000; 124:1532-9. [PMID: 11115871 PMCID: PMC1539309 DOI: 10.1104/pp.124.4.1532] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Affiliation(s)
- S I Gibson
- Department of Biochemistry and Cell Biology, MS140, Rice University, 6100 Main Street, Houston, Texas 77005-1892, USA.
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Fujiki Y, Ito M, Nishida I, Watanabe A. Multiple signaling pathways in gene expression during sugar starvation. Pharmacological analysis of din gene expression in suspension-cultured cells of Arabidopsis. PLANT PHYSIOLOGY 2000; 124:1139-48. [PMID: 11080291 PMCID: PMC59213 DOI: 10.1104/pp.124.3.1139] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2000] [Accepted: 07/11/2000] [Indexed: 05/20/2023]
Abstract
We have identified many dark-inducible (din) genes that are expressed in Arabidopsis leaves kept in the dark. In the present study we addressed the question of how plant cells sense the depletion of sugars, and how sugar starvation triggers din gene expression in suspension-cultured cells of Arabidopsis. Depletion of sucrose in the medium triggered marked accumulation of din transcripts. Suppression of din gene expression by 2-deoxy-Glc, and a non-suppressive effect exerted by 3-O-methyl-Glc, suggested that sugar-repressible expression of din genes is mediated through the phosphorylation of hexose by hexokinase, as exemplified in the repression of photosynthetic genes by sugars. We have further shown that the signaling triggered by sugar starvation involves protein phosphorylation and dephosphorylation events, and have provided the first evidence that multiple pathways of protein dephosphorylation exist in sugar starvation-induced gene expression. An inhibitor of serine/threonine protein kinase, K-252a, inhibited din gene expression in sugar-depleted cells. Okadaic acid, which may preferentially inhibit type 2A protein phosphatases over type 1, enhanced the transcript levels of all din genes, except din6 and din10, under sugar starvation. Conversely, a more potent inhibitor of type 1 and 2A protein phosphatases, calyculin A, increased transcripts from din2 and din9, but decreased those from other din genes, in sugar-depleted cells. On the other hand, calyculin A, but not okadaic acid, completely inhibited the gene expression of chlorophyll a/b-binding protein under sugar starvation. These results indicate that multiple signaling pathways, mediated by different types of protein phosphatases, regulate gene expression during sugar starvation.
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Affiliation(s)
- Y Fujiki
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Bunkyo-ku, Hongo, Tokyo 113-0033, Japan.
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Ikeda Y, Koizumi N, Kusano T, Sano H. Specific binding of a 14-3-3 protein to autophosphorylated WPK4, an SNF1-related wheat protein kinase, and to WPK4-phosphorylated nitrate reductase. J Biol Chem 2000; 275:31695-700. [PMID: 10918058 DOI: 10.1074/jbc.m004892200] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
WPK4 is a wheat protein kinase related to the yeast protein kinase SNF1, which plays a role in catabolite repression. To identify proteins involved in signal transduction through WPK4, we performed yeast two-hybrid screens and isolated two cDNA clones designated as TaWIN1 and TaWIN2. Both encode 14-3-3 proteins that, upon autophosphorylation, bind the C-terminal regulatory domain of WPK4. Mutational analysis through amino acid substitution revealed that TaWIN1 and TaWIN2 primarily bind WPK4 through phosphoserines at the positions 388 and 418, both located in the C-terminal region. Mutations in the conserved residues of the TaWIN1 amphipathic groove impaired the ability of TaWIN1 to bind to WPK4. A screen for in vitro phosphorylation of proteins involved in nutrient metabolism revealed a putative WPK4 substrate, nitrate reductase; its hinge 1 region was efficiently phosphorylated by WPK4. Subsequent far Western blots showed that it specifically bound TaWIN1. Since nitrate reductase has been shown to be inactivated by phosphorylation upon 14-3-3 binding, the present findings strongly suggest that WPK4 is the protein kinase responsible for controlling the nitrogen metabolic pathway, assembling the nitrate reductase and 14-3-3 complex through its phosphorylation specificity.
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Affiliation(s)
- Y Ikeda
- Research and Education Center for Genetic Information, Nara Institute of Science and Technology, Ikoma, Nara 630-0101, Japan
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