1
|
Wang H, Li N, Li H, Zhang S, Zhang X, Yan X, Wang Z, Yang Y, Zhang S. Overexpression of NtGCN2 improves drought tolerance in tobacco by regulating proline accumulation, ROS scavenging ability, and stomatal closure. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 198:107665. [PMID: 37018865 DOI: 10.1016/j.plaphy.2023.107665] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 03/18/2023] [Accepted: 03/23/2023] [Indexed: 05/07/2023]
Abstract
Drought stress is a severe threat to plants. Genes that respond to drought stress are essential for plant growth and development. General control nonderepressible 2 (GCN2) encodes a protein kinase that responds to various biotic and abiotic stresses. However, the mechanism of GCN2 in plant drought tolerance remains unclear. In the present study, the promoters of NtGCN2 from Nicotiana tabacum K326, which contained a drought-responsive Cis-acting element MYB that can be activated by drought stress, were cloned. Furthermore, the drought tolerance function of NtGCN2 was investigated using NtGCN2-overexpressed transgenic tobacco plants. NtGCN2-overexpressed transgenic plants were more tolerant to drought stress than wild-type (WT) plants. The transgenic tobacco plants exhibited higher proline and abscisic acid (ABA) contents, antioxidant enzyme activities, leaf relative water content, and expression levels of genes encoding key antioxidant enzymes and proline synthase, but lower levels of malondialdehyde and reactive oxygen species, and reduced stomatal apertures, stomatal densities, and stomatal opening rates compared to WT plants under drought stress. These results indicated that overexpression of NtGCN2 conferred drought tolerance in transgenic tobacco plants. RNA-seq analysis showed that overexpression of NtGCN2 responded to drought stress by regulating the expression of genes related to proline synthesis and catabolism, abscisic acid synthesis and catabolism, antioxidant enzymes, and ion channels in guard cells. These results showed that NtGCN2 might regulate drought tolerance by regulating proline accumulation, reactive oxygen species (ROS) scavenging, and stomatal closure in tobacco and may have the potential for application in the genetic modification of crop drought tolerance.
Collapse
Affiliation(s)
- Hao Wang
- National Tobacco Cultivation & Physiology & Biochemistry Research Centre, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Ning Li
- National Tobacco Cultivation & Physiology & Biochemistry Research Centre, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Hang Li
- National Tobacco Cultivation & Physiology & Biochemistry Research Centre, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Songjie Zhang
- National Tobacco Cultivation & Physiology & Biochemistry Research Centre, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Xiaoquan Zhang
- National Tobacco Cultivation & Physiology & Biochemistry Research Centre, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Xiaoxiao Yan
- National Tobacco Cultivation & Physiology & Biochemistry Research Centre, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Zhaojun Wang
- National Tobacco Cultivation & Physiology & Biochemistry Research Centre, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Yongxia Yang
- National Tobacco Cultivation & Physiology & Biochemistry Research Centre, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Songtao Zhang
- National Tobacco Cultivation & Physiology & Biochemistry Research Centre, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, Henan, China.
| |
Collapse
|
2
|
Schäfer M, Meza-Canales ID, Navarro-Quezada A, Brütting C, Vanková R, Baldwin IT, Meldau S. Cytokinin levels and signaling respond to wounding and the perception of herbivore elicitors in Nicotiana attenuata. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2015; 57:198-212. [PMID: 24924599 PMCID: PMC4286249 DOI: 10.1111/jipb.12227] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 06/11/2014] [Indexed: 05/21/2023]
Abstract
Nearly half a century ago insect herbivores were found to induce the formation of green islands by manipulating cytokinin (CK) levels. However, the response of the CK pathway to attack by chewing insect herbivores remains unclear. Here, we characterize the CK pathway of Nicotiana attenuata (Torr. ex S. Wats.) and its response to wounding and perception of herbivore-associated molecular patterns (HAMPs). We identified 44 genes involved in CK biosynthesis, inactivation, degradation, and signaling. Leaf wounding rapidly induced transcriptional changes in multiple genes throughout the pathway, as well as in the levels of CKs, including isopentenyladenosine and cis-zeatin riboside; perception of HAMPs present in the oral secretions (OS) of the specialist herbivore Manduca sexta amplified these responses. The jasmonate pathway, which triggers many herbivore-induced processes, was not required for these HAMP-triggered changes, but rather suppressed the CK responses. Interestingly CK pathway changes were observed also in systemic leaves in response to wounding and OS application indicating a role of CKs in mediating long distance systemic processes in response to herbivory. Since wounding and grasshopper OS elicited similar accumulations of CKs in Arabidopsis thaliana L., we propose that CKs are integral components of wounding and HAMP-triggered responses in many plant species.
Collapse
Affiliation(s)
- Martin Schäfer
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology07745, Jena, Germany
| | - Ivan D Meza-Canales
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology07745, Jena, Germany
| | - Aura Navarro-Quezada
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology07745, Jena, Germany
| | - Christoph Brütting
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology07745, Jena, Germany
| | - Radomira Vanková
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany AS CR165 02 Prague 6-Lysolaje, Czech Republic
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology07745, Jena, Germany
| | - Stefan Meldau
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology07745, Jena, Germany
- German Centre for integrative Biodiversity Research (iDiv)04107, Leipzig, Germany
| |
Collapse
|
3
|
Huang Z, Zhao L, Chen D, Liang M, Liu Z, Shao H, Long X. Salt stress encourages proline accumulation by regulating proline biosynthesis and degradation in Jerusalem artichoke plantlets. PLoS One 2013; 8:e62085. [PMID: 23637970 PMCID: PMC3639250 DOI: 10.1371/journal.pone.0062085] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 03/16/2013] [Indexed: 12/04/2022] Open
Abstract
Proline accumulation is an important mechanism for osmotic regulation under salt stress. In this study, we evaluated proline accumulation profiles in roots, stems and leaves of Jerusalem artichoke (Helianthus tuberosus L.) plantlets under NaCl stress. We also examined HtP5CS, HtOAT and HtPDH enzyme activities and gene expression patterns of putative HtP5CS1, HtP5CS2, HtOAT, HtPDH1, and HtPDH2 genes. The objective of our study was to characterize the proline regulation mechanisms of Jerusalem artichoke, a moderately salt tolerant species, under NaCl stress. Jerusalem artichoke plantlets were observed to accumulate proline in roots, stems and leaves during salt stress. HtP5CS enzyme activities were increased under NaCl stress, while HtOAT and HtPDH activities generally repressed. Transcript levels of HtP5CS2 increased while transcript levels of HtOAT, HtPDH1 and HtPDH2 generally decreased in response to NaCl stress. Our results supports that for Jerusalem artichoke, proline synthesis under salt stress is mainly through the Glu pathway, and HtP5CS2 is predominant in this process while HtOAT plays a less important role. Both HtPDH genes may function in proline degradation.
Collapse
Affiliation(s)
- Zengrong Huang
- Jiangsu Key Lab of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Coastal Biology and Bioesources Utilization, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Yantai, China
| | - Long Zhao
- Jiangsu Key Lab of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| | - Dandan Chen
- Jiangsu Key Lab of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| | - Mingxiang Liang
- Jiangsu Key Lab of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- * E-mail: (ML); (ZL); (HS)
| | - Zhaopu Liu
- Jiangsu Key Lab of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- * E-mail: (ML); (ZL); (HS)
| | - Hongbo Shao
- Jiangsu Key Lab of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Coastal Biology and Bioesources Utilization, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Yantai, China
- Institute for Life Sciences, Qingdao University of Science and Technology, Qingdao, China
- * E-mail: (ML); (ZL); (HS)
| | - Xiaohua Long
- Jiangsu Key Lab of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| |
Collapse
|
4
|
Dobrá J, Vanková R, Havlová M, Burman AJ, Libus J, Storchová H. Tobacco leaves and roots differ in the expression of proline metabolism-related genes in the course of drought stress and subsequent recovery. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:1588-97. [PMID: 21481968 DOI: 10.1016/j.jplph.2011.02.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 02/02/2011] [Accepted: 02/03/2011] [Indexed: 05/18/2023]
Abstract
In plants, members of gene families differ in function and mode of regulation. Fine-tuning of the expression of individual genes helps plants to cope with a variable environment. Genes encoding proline dehydrogenase (PDH), the key enzyme in proline degradation, and the proline biosynthetic enzyme, Δ(1)-pyrroline-5-carboxylate synthetase (P5CS), play an important role in responses to osmotic and drought stresses. We compared the expression patterns of three PDH and two putative P5CS genes during drought stress progression and subsequent recovery. Whereas the NtPDH1 gene was affected little by dehydration or rehydration, the NtPDH2 gene responded rapidly to both conditions, and was down-regulated under drought. The CIG1 gene, encoding cytokinin-inducible PDH, exhibited an intermediate transcription pattern. Whereas P5CS B was not affected by the stress conditions, the P5CS A gene was highly up-regulated during drought stress. CIG1 and NtPDH1 transcription was not activated, and P5CS A was only partially reduced in leaves within 24-h after rehydration, a re-watering period sufficient for large physiological changes to occur. The lack of activation of tobacco PDH genes and incomplete reduction of the P5CS A gene in leaves within 24-h of rehydration may reflect the need for the protection of plants to potential subsequent stresses. The data indicate that recovery is a specific physiological process following different patterns in leaves and roots.
Collapse
Affiliation(s)
- Jana Dobrá
- Institute of Experimental Botany, v.v.i., Academy of Sciences of the Czech Republic, Rozvojová 263, 165 02 Prague 6, Lysolaje, Czech Republic
| | | | | | | | | | | |
Collapse
|
5
|
Ribarits A, Abdullaev A, Tashpulatov A, Richter A, Heberle-Bors E, Touraev A. Two tobacco proline dehydrogenases are differentially regulated and play a role in early plant development. PLANTA 2007; 225:1313-24. [PMID: 17106685 DOI: 10.1007/s00425-006-0429-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2006] [Accepted: 10/10/2006] [Indexed: 05/12/2023]
Abstract
Proline dehydrogenase is the rate-limiting enzyme in proline degradation and serves important functions in the stress responses and development of plants. We isolated two tobacco proline dehydrogenases, NtPDH1 and NtPDH2, in the course of screening for genes upregulated in stressed tobacco (Nicotiana tabacum) microspores. Expression analysis revealed that the two genes are differentially regulated. Under unstressed conditions, their steady-state transcript levels were similar in mature pollen and apical meristems, whereas NtPDH2 was expressed predominantly in vegetative organs, styles, and ovules. The expression of NtPDH1 was maintained at a constant low level during 24 h of dehydration, whereas NtPDH2 was upregulated within 1 h after the onset of stress and subsequently downregulated to undetectable levels. Differential and sustained expression was also found for the two enzymatic isoforms of Arabidopsis thaliana AtPDH. Silencing of the NtPDH genes by RNA interference using the CaMV 35S promoter led to increased proline contents, decreased seed set, delayed seed germination and retarded seedling development pointing towards an important function of at least one of the two NtPDH genes during plant reproductive development.
Collapse
Affiliation(s)
- Alexandra Ribarits
- Max F. Perutz Laboratories, University Departments at the Vienna Biocenter, Department of Plant Molecular Biology, University of Vienna, Dr. Bohrgasse 9, 1030 Wien, Austria
| | | | | | | | | | | |
Collapse
|
6
|
Simón-Mateo C, Depuydt S, DE Oliveira Manes CL, Cnudde F, Holsters M, Goethals K, Vereecke D. The phytopathogen Rhodococcus fascians breaks apical dominance and activates axillary meristems by inducing plant genes involved in hormone metabolism. MOLECULAR PLANT PATHOLOGY 2006; 7:103-112. [PMID: 20507431 DOI: 10.1111/j.1364-3703.2006.00322.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
SUMMARY Rhodococcus fascians is a Gram-positive bacterium that interacts with many plant species and induces multiple shoots through a combination of activation of dormant axillary meristems and de novo meristem formation. Although phenotypic analysis of the symptoms of infected plants clearly demonstrates a disturbance of the phytohormonal balance and an activation of the cell cycle, the actual mechanism of symptom development and the targets of the bacterial signals are unknown. To elucidate the molecular pathways that are responsive to R. fascians infection, differential display was performed on Nicotiana tabacum as a host. Four differentially expressed genes could be identified that putatively encode a senescence-associated protein, a gibberellin 2-oxidase, a P450 monooxygenase and a proline dehydrogenase. The differential expression of the three latter genes was confirmed on infected Arabidopsis thaliana plants by quantitative reverse transcription polymerase chain reactions, supporting their general function in R. fascians-induced symptom development. The role of these genes in hormone metabolism, especially of gibberellin and abscisic acid, in breaking apical dominance and in activating axillary meristems, which are processes associated with symptom development, is discussed.
Collapse
Affiliation(s)
- Carmen Simón-Mateo
- Department of Plant Systems Biology, Flanders Interuniversity Institute for Biotechnology (VIB), Ghent University, Technologiepark 927, B-9052 Gent, Belgium
| | | | | | | | | | | | | |
Collapse
|
7
|
Matsuoka K, Demura T, Galis I, Horiguchi T, Sasaki M, Tashiro G, Fukuda H. A comprehensive gene expression analysis toward the understanding of growth and differentiation of tobacco BY-2 cells. PLANT & CELL PHYSIOLOGY 2004; 45:1280-9. [PMID: 15509851 DOI: 10.1093/pcp/pch155] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
To understand how plant cell changes gene expression during cell division and after termination of cell division, we analyzed the change of gene expression during the growth of tobacco BY-2 cell lines using a cDNA microarray, which contained about 9,200 expression sequence tag fragments and corresponded to about 7,000 genes. We found that log phase cells predominantly expressed DNA/chromosome duplication gene homologs. In addition, many genes for basic transcription and translation machineries, as well as proteasomal genes, were up-regulated at the log phase. About half of the kinesin homolog genes, but not myosin homolog genes, were predominantly expressed at the dividing phase as well. In contrast, stationary phase cells expressed genes for many receptor kinases, signal transduction machineries and transcription factors. Several hundreds of genes showed differential expression after incubation of stationary phase cells with medium containing either salicylic acid or abscisic acid. These findings suggested that BY-2 cells at the stationary phase express genes for perceiving extracellular signals.
Collapse
Affiliation(s)
- Ken Matsuoka
- Plant Science Center, RIKEN (Institute of Physical and Chemical Research), 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045 Japan.
| | | | | | | | | | | | | |
Collapse
|