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1.
PLoS One ; 15(8): e0236129, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760076

RESUMO

Salix matsudana, a member of Salicaceae, is an important ornamental tree in China. Because of its capability to tolerate high salt conditions, S. matsudana also plays an important ecological role when grown along Chinese coastal beaches, where the salinity content is high. Here, we aimed to elucidate the mechanism of higher salt tolerance in S. matsudana variety '9901' by identifying the associated genes through RNA sequencing and comparing differential gene expression between the S. matsudana salt-tolerant and salt-sensitive samples treated with 150 mM NaCl. Transcriptomic comparison of the roots of the two samples revealed 2174 and 3159 genes responsive to salt stress in salt-sensitive and salt-tolerant sample, respectively. Real-time polymerase chain reaction analysis of 9 of the responsive genes revealed a strong, positive correlation with RNA sequencing data. The genes were enriched in several pathways, including carbon metabolism pathway, plant-pathogen interaction pathway, and plant hormone signal transduction pathway. Differentially expressed genes (DEGs) encoding transcription factors associated with abiotic stress responses and salt stress response network were identified; their expression levels differed between the two samples in response to salt stress. Hub genes were also revealed by weighted gene co-expression network (WGCNA) analysis. For functional analysis of the DEG encoding sedoheptulose-1,7-bisphosphatase (SBPase), the gene was overexpressed in transgenic Arabidopsis, resulting in increased photosynthetic rates, sucrose and starch accumulation, and enhanced salt tolerance. Further functional characterization of other hub DEGs will reveal the molecular mechanism of salt tolerance in S. matsudana and allow the application of S. matsudana in coastal afforestation.


Assuntos
Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes/fisiologia , Salix/fisiologia , Tolerância ao Sal/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Fotossíntese/genética , Raízes de Plantas , Plantas Geneticamente Modificadas , RNA-Seq , Salinidade , Amido/metabolismo , Sacarose/metabolismo
2.
Sheng Wu Gong Cheng Xue Bao ; 36(7): 1356-1364, 2020 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-32748593

RESUMO

Salinity is the most important factor for the growth of crops. It is an effective method to alleviate the toxic effect caused by salt stress using saline-alkali-tolerant and growth-promoting bacteria in agriculture. Seven salt-tolerant bacteria were screened from saline-alkali soil, and the abilities of EPS production, alkalinity reduction and IAA production of the selected strains were investigated. A dominant strain DB01 was evaluated. The abilities of EPS production, alkalinity reduction and IAA production of strain DB01 were 0.21 g/g, 8.7% and 8.97 mg/L, respectively. The isolate was identified as Halomonas aquamarina by partial sequencing analysis of its 16S rRNA genes, and had the ability to inhibit the growth of Fusarium oxysporum f. sp., Alternaria solani, Phytophthora sojae and Rhizoctonia cerealis. It also could promote root length and germination rate of wheat seedlings under salt stress. Halomonas aquamarina can provide theoretical basis for the development of soil microbial resources and the application in saline-alkali soil improvement.


Assuntos
Álcalis , Raízes de Plantas , Tolerância ao Sal , Microbiologia do Solo , Álcalis/metabolismo , Bactérias/efeitos dos fármacos , Bactérias/genética , Halomonas/genética , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Tolerância ao Sal/genética , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Solo/química , Triticum/microbiologia
3.
PLoS One ; 15(7): e0236037, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32701981

RESUMO

Soil salinity imposes an agricultural and economic burden that may be alleviated by identifying the components of salinity tolerance in barley, a major crop and the most salt tolerant cereal. To improve our understanding of these components, we evaluated a diversity panel of 377 two-row spring barley cultivars during both the vegetative, in a controlled environment, and the reproductive stages, in the field. In the controlled environment, a high-throughput phenotyping platform was used to assess the growth-related traits under both control and saline conditions. In the field, the agronomic traits were measured from plots irrigated with either fresh or saline water. Association mapping for the different components of salinity tolerance enabled us to detect previously known associations, such as HvHKT1;5. Using an "interaction model", which took into account the interaction between treatment (control and salt) and genetic markers, we identified several loci associated with yield components related to salinity tolerance. We also observed that the two developmental stages did not share genetic regions associated with the components of salinity tolerance, suggesting that different mechanisms play distinct roles throughout the barley life cycle. Our association analysis revealed that genetically defined regions containing known flowering genes (Vrn-H3, Vrn-H1, and HvNAM-1) were responsive to salt stress. We identified a salt-responsive locus (7H, 128.35 cM) that was associated with grain number per ear, and suggest a gene encoding a vacuolar H+-translocating pyrophosphatase, HVP1, as a candidate. We also found a new QTL on chromosome 3H (139.22 cM), which was significant for ear number per plant, and a locus on chromosome 2H (141.87 cM), previously identified using a nested association mapping population, which associated with a yield component and interacted with salinity stress. Our study is the first to evaluate a barley diversity panel for salinity stress under both controlled and field conditions, allowing us to identify contributions from new components of salinity tolerance which could be used for marker-assisted selection when breeding for marginal and saline regions.


Assuntos
Cromossomos de Plantas , Hordeum/genética , Tolerância ao Sal/genética , Flores/genética , Flores/metabolismo , Genótipo , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Pirofosfatase Inorgânica/genética , Fenótipo , Proteínas de Plantas/genética , Locos de Características Quantitativas , Solo/química
4.
Plant Mol Biol ; 103(4-5): 545-560, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32504260

RESUMO

KEY MESSAGE: OsGTγ-2, a trihelix transcription factor, is a positive regulator of rice responses to salt stress by regulating the expression of ion transporters. Salinity stress seriously restricts rice growth and yield. Trihelix transcription factors (GT factors) specifically bind to GT elements and play a diverse role in plant morphological development and responses to abiotic stresses. In our previous study, we found that the GT-1 element (GAAAAA) is a key element in the salinity-induced OsRAV2 promoter. Here, we identified a rice OsGTγ family member, OsGTγ-2, which directly interacted with the GT-1 element in the OsRAV2 promoter. OsGTγ-2 specifically targeted the nucleus, was mainly expressed in roots, sheathes, stems and seeds, and was induced by salinity, osmotic and oxidative stresses and abscisic acid (ABA). The seed germination rate, seedling growth and survival rate under salinity stress was improved in OsGTγ-2 overexpressing lines (PZmUbi::OsGTγ-2). In contrast, CRISPR/Cas9-mediated OsGTγ-2 knockout lines (osgtγ-2) showed salt-hypersensitive phenotypes. In response to salt stress, different Na+ and K+ acclamation patterns were observed in PZmUbi::OsGTγ-2 lines and osgtγ-2 plants were observed. The molecular mechanism of OsGTγ-2 in rice salt adaptation was also investigated. Several major genes responsible for ion transporting, such as the OsHKT2; 1, OsHKT1; 3 and OsNHX1 were transcriptionally regulated by OsGTγ-2. A subsequent yeast one-hybrid assay and EMSA indicated that OsGTγ-2 directly interacted with the promoters of OsHKT2; 1, OsNHX1 and OsHKT1; 3. Taken together, these results suggest that OsGTγ-2 is an important positive regulator involved in rice responses to salt stress and suggest a potential role for OsGTγ-2 in regulating salinity adaptation in rice.


Assuntos
Aclimatação/fisiologia , Proteínas de Ligação a DNA/metabolismo , Oryza/fisiologia , Estresse Salino/fisiologia , Tolerância ao Sal/genética , Fatores de Transcrição/metabolismo , Ácido Abscísico/metabolismo , Aclimatação/genética , Adaptação Fisiológica , Sistemas CRISPR-Cas , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Desenvolvimento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Salinidade , Plântula/genética , Sementes/metabolismo , Sódio/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Estresse Fisiológico/genética , Simportadores/metabolismo , Fatores de Transcrição/genética
5.
Gene ; 753: 144803, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32446917

RESUMO

R2R3-type MYBs are a key group of regulatory factors that control diverse developmental processes and stress tolerance in plants. Soybean is a major legume crop with the richness of seed protein and edible vegetable oil, and 244 R2R3-type MYBs have been identified in soybean. However, the knowledge regarding their functional roles has been greatly limited as yet. In this study, a novel R2R3-type MYB (GmMYB81) was functionally characterized in soybean, and it is closely related to two abiotic stress-associated regulators (AtMYB44 and AtMYB77). GmMYB81 transcripts not only differentially accumulated in soybean tissues and during embryo development, but also were significantly enhanced by drought, salt and cold stress. Histochemical GUS assay in Arabidopsis indicated that GmMYB81 promoter showed high activity in seedlings, rosette leaves, inflorescences, silique wall, mature anthers, roots, and germinating seeds. Further investigation indicated that over-expression of GmMYB81 in Arabidopsis caused auxin-associated phenotypes, including small flower and silique, more branch, and weakened apical dominance. Moreover, over-expression of GmMYB81 significantly elevated the rates of seed germination and green seedling under salt and drought stress, indicating that GmMYB81 might confer plant tolerance to salt and drought stress during seed germination. Additionally, protein interaction analysis showed that GmMYB81 interacts with the abiotic stress regulator GmSGF14l. Further observation indicated that they displayed similar expression patterns under drought and salt stress, suggesting GmMYB81 and GmSGF14l might cooperatively affect stress tolerance. These findings will facilitate future investigations of the regulatory mechanisms of GmMYB81 in response to plant stress tolerance, especially seed germination under abiotic stresses.


Assuntos
Proteínas de Arabidopsis/genética , Soja/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Ácido Abscísico/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Secas , Fabaceae/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Germinação/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Estresse Salino/genética , Tolerância ao Sal/genética , Sementes/metabolismo , Fatores de Transcrição/metabolismo
6.
Gene ; 753: 144802, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32454178

RESUMO

Synchronous and timely regulation of multiple genes results in an effective defense response that decides the fate of the host when challenged with pathogens or unexpected changes in environmental conditions. One such gene, which is downregulated in response to multiple bacterial pathogens, is a putative nonspecific lipid transfer protein (nsLTP) of unknown function that we have named DISEASE RELATED NONSPECIFIC LIPID TRANSFER PROTEIN 1 (DRN1). We show that upon pathogen challenge, DRN1 is strongly downregulated, while a putative DRN1-targeting novel microRNA (miRNA) named DRN1 Regulating miRNA (DmiR) is reciprocally upregulated. Furthermore, we provide evidence that DRN1 is required for defense against bacterial and fungal pathogens as well as for normal seedling growth under salinity stress. Although nsLTP family members from different plant species are known to be a significant source of food allergens and are often associated with antimicrobial properties, our knowledge on the biological functions and regulation of this gene family is limited. Our current work not only sheds light on the mechanism of regulation but also helps in the functional characterization of DRN1, a putative nsLTP family member of hitherto unknown function.


Assuntos
Arabidopsis/genética , Proteínas de Transferência de Fosfolipídeos/genética , Estresse Salino/genética , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Resistência à Doença/genética , Secas , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Transferência de Fosfolipídeos/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Patologia Vegetal , Plantas Geneticamente Modificadas , Salinidade , Tolerância ao Sal/genética , Plântula/genética , Estresse Fisiológico/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-32240936

RESUMO

Salt is a major abiotic stress that negatively impacts plant growth and development. Research on the mechanisms of plant salt tolerance and the breeding of salt-tolerant plants is becoming an important research field. Transcription factors are master regulators that control the expression of many target genes, helping to regulate the response of plants to adverse conditions. GRAS are plant-specific transcription factors that play various roles in plant development and stress responses. However, the function of a GRAS gene identified in Halostachys caspica, a salt-tolerant plant with important ecological value, has not been determined. In this study, we characterized a novel gene (HcSCL13) encoding a GRAS transcription factor from H. caspica. Quantitative real-time (qRT)-PCR results indicated that HcSCL13 expression was induced by salt, drought and application of stress-related phytohormone abscisic acid (ABA). The HcSCL13 protein was localized in the nucleus with transactivation activity at the N terminus. Heterologous overexpression of HcSCL13 enhanced plant growth and salt tolerance in transgenic Arabidopsis. With HcSCL13 overexpression, plants had enhanced growth, as well as greater chlorophyll content, fresh weight and root elongation compared to the wild type. Transcriptomic analysis revealed that HcSCL13 overexpression affected the response to light/abiotic stimulus/hormone/organic substance, plant hormone signal-related and plant growth and development genes under normal and saline stress conditions. Taken together, these results indicate that HcSCL13 genes can modulate salt stress tolerance in Arabidopsis through the regulation of plant growth and the activation of gene expression.


Assuntos
Arabidopsis , Chenopodiaceae , Expressão Gênica , Desenvolvimento Vegetal , Plantas Geneticamente Modificadas , Tolerância ao Sal , Fatores de Transcrição , Arabidopsis/genética , Chenopodiaceae/genética , Desenvolvimento Vegetal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tolerância ao Sal/genética , Fatores de Transcrição/genética
8.
Artigo em Inglês | MEDLINE | ID: mdl-32251957

RESUMO

Soil salinity of fields is often non-uniform. To obtain a better understanding of molecular response to non-uniform salt stress, we conducted transcriptomic analysis on the leaves and roots of alfalfa grown under 0/0, 200/200, and 0/200 mM NaCl treatments. A total of 233,742 unigenes were obtained from the assembled cDNA libraries. There were 98 and 710 unigenes identified as significantly differentially expressed genes (DEGs) in the leaves of non-uniform and uniform salt treatment, respectively. Furthermore, there were 5178 DEGs in the roots under uniform salt stress, 273 DEGs in the non-saline side and 4616 in the high-saline side roots under non-uniform salt stress. Alfalfa treated with non-uniform salinity had greater dry weight and less salt damage compared to treatment with uniform salinity. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of the DEGs in roots revealed that both sides of the non-uniform salinity were enriched in pathways related to "phenylpropanoid biosynthesis" and "linoleic acid metabolism"; and "MAPK signaling pathway-plant" was also indicated as a key pathway in the high-saline roots. We also combined a set of important salt-response genes and found that roots from the non-saline side developed more roots with increased water uptake by altering the expression of aquaporins and genes related to growth regulation. Moreover, the hormone signal transduction and the antioxidant pathway probably play important roles in inducing more salt-related genes and increasing resistance to non-uniform salt stress on both sides of the roots.


Assuntos
Medicago sativa , Tolerância ao Sal , Transcriptoma , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Medicago sativa/genética , Medicago sativa/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Salinidade , Estresse Salino/genética , Tolerância ao Sal/genética
9.
Tree Physiol ; 40(9): 1292-1311, 2020 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-32334430

RESUMO

ZINC FINGER OF ARABIDOPSIS THALIANA12 (ZAT12) plays an important role in stress responses, but the transcriptional regulation of ZAT12 in response to abiotic stress remains unclear. In this study, we confirmed that a SALT TOLERANCE ZINC FINGER1 transcription factor from Populus euphratica (PeSTZ1) could regulate the expression of PeZAT12 by dual-luciferase reporter (DLR) assay and electrophoretic mobility shift assay. The expression of PeSTZ1 was rapidly induced by NaCl and hydrogen peroxide (H2O2) treatments. Overexpressing PeSTZ1 in poplar 84K (Populus alba × Populus glandulosa) plant was endowed with a strong tolerance to salt stress. Under salt stress, transgenic poplar exhibited higher expression levels of PeZAT12 and accumulated a larger amount of antioxidant than the wild-type plants. Meanwhile, ASCORBATE PEROXIDASE2 (PeAPX2) can be activated by PeZAT12 and PeSTZ1, promoting the accumulation of cytosolic ascorbate peroxidase (APX) to scavenge reactive oxygen species (ROS) under salt stress. This new regulatory model (PeSTZ1-PeZAT12-PeAPX2) was found in poplar, providing a new idea and insight for the interpretation of poplar resistance. Transgenic poplar reduced the accumulation of ROS, restrained the degradation of chlorophyll and guaranteed the photosynthesis and electron transport system. On the other hand, transgenic poplar slickly adjusted K+/Na+ homeostasis to alleviate salt toxicity in photosynthetic organs of plants under salt stress and then increased biomass accumulation. In summary, PeSTZ1 confers salt stress tolerance by scavenging the accumulation of ROS through regulating the expression of PeZAT12 and PeAPX2 in poplar.


Assuntos
Populus/genética , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Espécies Reativas de Oxigênio , Estresse Salino , Tolerância ao Sal/genética , Estresse Fisiológico
10.
PLoS One ; 15(4): e0230958, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32294092

RESUMO

Soil salinization is a serious problem for cultivation of rice, as among cereals rice is the most salt sensitive crop, and more than 40% of the total agricultural land amounting to approximately 80 million ha the world over is salt affected. Salinity affects a plant in a varieties of ways, including ion toxicity, osmotic stress and oxidative damage. Since miRNAs occupy the top place in biochemical events determining a trait, understanding their role in salt tolerance is highly desirable, which may allow introduction of the trait in the rice cultivars of choice through biotechnological interventions. High throughput sequencing of sRNAs in the root and shoot tissues of the seedlings of the control and NaCl treated Pokkali, a salt-tolerant rice variety, identified 75 conserved miRNAs and mapped 200 sRNAs to the rice genome as novel miRNAs. Expression of nine novel miRNAs and two conserved miRNAs were confirmed by Northern blotting. Several of both conserved and novel miRNAs that expressed differentially in root and/or shoot tissues targeted transcription factors like AP2/EREBP domain protein, ARF, NAC, MYB, NF-YA, HD-Zip III, TCP and SBP reported to be involved in salt tolerance or in abiotic stress tolerance in general. Most of the novel miRNAs expressed in the salt tolerant wild rice Oryza coarctata, suggesting conservation of miRNAs in taxonomically related species. One of the novel miRNAs, osa-miR12477, also targeted L-ascorbate oxidase (LAO), indicating build-up of oxidative stress in the plant upon salt treatment, which was confirmed by DAB staining. Thus, salt tolerance might involve miRNA-mediated regulation of 1) cellular abundance of the hormone signaling components like EREBP and ARF, 2) synthesis of abiotic stress related transcription factors, and 3) antioxidative component like LAO for mitigation of oxidative damage. The study clearly indicated importance of osa-miR12477 regulated expression of LAO in salt tolerance in the plant.


Assuntos
MicroRNAs/genética , Oryza/genética , Tolerância ao Sal/genética , Northern Blotting/métodos , Regulação da Expressão Gênica de Plantas/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Estresse Oxidativo/genética , Salinidade , Plântula/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genética
11.
PLoS One ; 15(4): e0227496, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267864

RESUMO

Atlantic salmon migrate to sea following completion of a developmental process known as smolting, which establishes a seawater (SW) tolerant phenotype. Smolting is stimulated by exposure to long photoperiod or continuous light (LL) following a period of exposure to short photoperiod (SP), and this leads to major changes in gill ion exchange and osmoregulatory function. Here, we performed an RNAseq experiment to discover novel genes involved in photoperiod-dependent remodeling of the gill. This revealed a novel cohort of genes whose expression rises dramatically in fish transferred to LL following SP exposure, but not in control fish maintained continuously on LL or on SP. A follow-up experiment revealed that the SP-history dependence of LL induction of gene expression varies considerably between genes. Some genes were inducible by LL exposure after only 2 weeks exposure to SP, while others required 8 weeks prior SP exposure for maximum responsiveness to LL. Since subsequent SW growth performance is also markedly improved following 8 weeks SP exposure, these photoperiodic history-dependent genes may be useful predictive markers for full smolt development.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Fotoperíodo , Salmo salar/fisiologia , Tolerância ao Sal/genética , Água do Mar/efeitos adversos , Migração Animal/fisiologia , Animais , Brânquias/crescimento & desenvolvimento , Estágios do Ciclo de Vida/fisiologia , Noruega , RNA-Seq , Fatores de Tempo
12.
Electron. j. biotechnol ; 44: 19-24, Mar. 2020. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1087631

RESUMO

BACKGROUND: Pyruvic acid (PA), a vital α-oxocarboxylic acid, plays an important role in energy and carbon metabolism. The oleaginous yeast Yarrowia lipolytica (Y. lipolytica) has considerable potential for the production of PA. An increased NaCl concentration reportedly increases the biomass and PA yield of Y. lipolytica. RESULTS: To increase the yield of PA, the NaCl-tolerant Y. lipolytica A4 mutant was produced using the atmospheric and room temperature plasma method of mutation. The A4 mutant showed growth on medium containing 160 g/L NaCl. The PA yield of the A4 mutant reached 97.2 g/L at 120 h (0.795 g/g glycerol) in a 20-L fermenter with glycerol as the sole carbon source, which was 28.9% higher than that of the parental strain. CONCLUSION: The PA yield from Y. lipolytica can be improved by increasing its NaCl tolerance.


Assuntos
Ácido Pirúvico/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Pressão Osmótica , Leveduras , Carbono/metabolismo , Cloreto de Sódio , Reatores Biológicos , Tolerância ao Sal/genética , Fermentação , Glicerol/metabolismo , Mutação
13.
PLoS One ; 15(3): e0229513, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187229

RESUMO

Considering the complex nature of salinity tolerance mechanisms, the use of isogenic lines or mutants possessing the same genetic background albeit different tolerance to salinity is a suitable method for reduction of analytical complexity to study these mechanisms. In the present study, whole transcriptome analysis was evaluated using RNA-seq method between a salt-tolerant mutant line "M4-73-30" and its wild-type "Zarjou" cultivar at seedling stage after six hours of exposure to salt stress (300 mM NaCl). Transcriptome sequencing yielded 20 million reads for each genotype. A total number of 7116 transcripts with differential expression were identified, 1586 and 1479 of which were obtained with significantly increased expression in the mutant and the wild-type, respectively. In addition, the families of WRKY, ERF, AP2/EREBP, NAC, CTR/DRE, AP2/ERF, MAD, MIKC, HSF, and bZIP were identified as the important transcription factors with specific expression in the mutant genotype. The RNA-seq results were confirmed at several time points using qRT-PCR for some important salt-responsive genes. In general, the results revealed that the mutant accumulated higher levels of sodium ion in the root and decreased its transfer to the shoot. Also, the mutant increased the amount of potassium ion leading to the maintenance a high ratio [K+]/[Na+] in the shoot compared to its wild-type via fast stomata closure and consequently transpiration reduction under the salt stress. Moreover, a reduction in photosynthesis and respiration was observed in the mutant, resulting in utilization of the stored energy and the carbon for maintaining the plant tissues, which is considered as a mechanism of salt tolerance in plants. Up-regulation of catalase, peroxidase, and ascorbate peroxidase genes has resulted in higher accumulation of H2O2 in the wild-type compared to the mutant. Therefore, the wild-type initiated rapid ROS signals which led to less oxidative scavenging in comparison with the mutant. The mutant increased expression in the ion transporters and the channels related to the salinity to maintain the ion homeostasis. In overall, the results demonstrated that the mutant responded better to the salt stress under both osmotic and ionic stress phases and lower damage was observed in the mutant compared to its wild-type under the salt stress.


Assuntos
Hordeum/genética , Transporte de Íons/genética , Tolerância ao Sal/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Genótipo , Transporte de Íons/fisiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Potássio/metabolismo , RNA-Seq/métodos , Salinidade , Plantas Tolerantes a Sal/genética , Análise de Sequência de RNA/métodos , Sódio/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma/genética , Sequenciamento Completo do Exoma/métodos
14.
PLoS One ; 15(2): e0228199, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32040520

RESUMO

In the present study, we identified salt stress tolerant genes from the marine bacterium Staphylococcus sp. strain P-TSB-70 through transcriptome sequencing. In favour of whole-genome transcriptome profiling of Staphylococcus sp. strain P-TSB-70 (GenBank Accn. No. KP117091) which tolerated upto 20% NaCl stress, the strain was cultured in the laboratory condition with 20% NaCl stress. Transcriptome analyses were performed by SOLiD4.0 sequencing technology from which 10280 and 9612 transcripts for control and treated, respectively, were obtained. The coverage per base (CPB) statistics were analyzed for both the samples. Gene ontology (GO) analysis has been categorized at varied graph levels based on three primary ontology studies viz. cellular components, biological processes, and molecular functions. The KEGG analysis of the assembled transcripts using KAAS showed presumed components of metabolic pathways which perhaps implicated in diverse metabolic pathways responsible for salt tolerance viz. glycolysis/gluconeogenesis, oxidative phosphorylation, glutathione metabolism, etc. further involving in salt tolerance. Overall, 90 salt stress tolerant genes were identified as of 186 salt-related transcripts. Several genes have been found executing normally in the TCA cycle pathway, integral membrane proteins, generation of the osmoprotectants, enzymatic pathway associated with salt tolerance. Recognized genes fit diverse groups of salt stress genes viz. abc transporter, betaine, sodium antiporter, sodium symporter, trehalose, ectoine, and choline, that belong to different families of genes involved in the pathway of salt stress. The control sample of the bacterium showed elevated high proportion of transcript contigs (29%) while upto 20% salt stress treated sample of the bacterium showed a higher percentage of transcript contigs (31.28%). A total of 1,288 and 1,133 transcript contigs were measured entirely as novel transcript contigs in both control and treated samples, respectively. The structure and function of 10 significant salt stress tolerant genes of Staphylococcus sp. have been analyzed in this study. The information acquired in the present study possibly used to recognize and clone the salt stress tolerant genes and support in developing the salt stress-tolerant plant varieties to expand the agricultural productivity in the saline system.


Assuntos
Tolerância ao Sal/genética , Água do Mar/microbiologia , Staphylococcus/genética , Transcriptoma , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Mapeamento de Sequências Contíguas , Perfilação da Expressão Gênica , Genoma Bacteriano , Índia , Redes e Vias Metabólicas/genética , Estrutura Terciária de Proteína , RNA Bacteriano/química , RNA Bacteriano/metabolismo , Staphylococcus/isolamento & purificação
15.
Gene ; 738: 144460, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32045659

RESUMO

MicroRNA390 (miR390), an ancient and highly conserved miRNA family in land plants, plays multiple roles in plant growth, development and stress responses. In this study, we isolated and identified MIR390, miR390, TAS3a/b/c, tasiARF-1/2/3 (trans-acting small interfering RNAs influencing Auxin Response Factors) and ARF2/3/4 in Jerusalem artichoke (Helianthus tuberosus L.). Treatment with 100 mM NaCl induced expression of miR390, increased cleavage of TAS3, produced high levels of tasiARFs, and subsequently enhanced cleavage of ARF3/4, which was most likely associated with salt tolerance of the plants. In contrast, treatment with 300 mM NaCl inhibited expression of miR390, attenuated cleavage of TAS3, produced a small amount of tasiARFs, and reduced cleavage of ARF3/4. We proposed that ARF2, one of the targets of tasiARFs, induced under salinity was likely to play an active role in salt tolerance of Jerusalem artichoke. The study of the miR390-TAS3-ARF model in Jerusalem artichoke may broaden our understanding of salt tolerance mechanisms, and provides a theoretical support for further genetic identification and breeding crops with increased tolerance to salt stress.


Assuntos
Helianthus/metabolismo , MicroRNAs/metabolismo , Estresse Salino/fisiologia , Regulação da Expressão Gênica de Plantas , Helianthus/genética , MicroRNAs/genética , Raízes de Plantas/genética , RNA de Plantas/genética , RNA Interferente Pequeno/genética , Salinidade , Estresse Salino/genética , Tolerância ao Sal/genética
16.
PLoS One ; 15(2): e0229023, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32097425

RESUMO

Persimmon (Diospyros kaki Thunb.) production is facing important problems related to climate change in the Mediterranean areas. One of them is soil salinization caused by the decrease and change of the rainfall distribution. In this context, there is a need to develop cultivars adapted to the increasingly challenging soil conditions. In this study, a backcross between (D. kaki x D. virginiana) x D. kaki was conducted, to unravel the mechanism involved in salinity tolerance of persimmon. The backcross involved the two species most used as rootstock for persimmon production. Both species are clearly distinct in their level of tolerance to salinity. Variables related to growth, leaf gas exchange, leaf water relations and content of nutrients were significantly affected by saline stress in the backcross population. Water flow regulation appears as a mechanism of salt tolerance in persimmon via differences in water potential and transpiration rate, which reduces ion entrance in the plant. Genetic expression of eight putative orthologous genes involved in different mechanisms leading to salt tolerance was analyzed. Differences in expression levels among populations under saline or control treatment were found. The 'High affinity potassium transporter' (HKT1-like) reduced its expression levels in the roots in all studied populations. Results obtained allowed selection of tolerant rootstocks genotypes and describe the hypothesis about the mechanisms involved in salt tolerance in persimmon that will be useful for breeding salinity tolerant rootstocks.


Assuntos
Cruzamentos Genéticos , Diospyros/genética , Diospyros/metabolismo , Fenótipo , Salinidade , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Variação Biológica da População , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Folhas de Planta/metabolismo
17.
Tree Physiol ; 40(6): 717-730, 2020 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-32083670

RESUMO

Salinity restricts the growth of trees to varying extents, but the regulatory mechanisms involved in their varying salt tolerance are largely unknown. In an effort to elucidate these mechanisms, we identified a total of 99 genes in the Ethylene Responsive Factor (ERF) family of transcription factors and examined their expression patterns under salt stress in Populus alba var. pyramidalis. We found that a B4 group gene, PalERF109, was rapidly induced by salt treatment and preferentially expressed in stems and petioles, where it is probably involved in transport of ions and water in xylem. Overexpression of PalERF109 enhanced the salt tolerance of the poplar, and further analysis showed that it directly upregulated a high-affinity K+transporter (HKT) gene, PalHKT1;2. The results clearly indicate that PalERF109 enhances salt tolerance at least partially through direct activation of PalHKT1;2 and extends understanding of the roles of ERF genes in tree stress responses.


Assuntos
Populus/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Tolerância ao Sal/genética , Estresse Fisiológico , Fatores de Transcrição/genética , Árvores
18.
Artigo em Inglês | MEDLINE | ID: mdl-31901883

RESUMO

Salt stress limits crop productivity worldwide, particularly in arid and heavily irrigated regions. Salt stress causes oxidative stress, in which plant cells accumulate harmful levels of reactive oxygen species (ROS). Thioredoxins (Trxs; EC 1.8.4.8) are antioxidant proteins encoded by a ubiquitous multigene family. Arabidopsis thaliana Trx h-type proteins localize in the cytoplasm and other subcellular organelles, and function in plant responses to abiotic stresses and pathogen attack. Here, we isolated the Arabidopsis genes encoding two cytosolic h-type Trx proteins, AtTrx-h2 and AtTrx-h3 and generated transgenic oilseed rape (Brassica napus) plants overexpressing AtTrx-h2 or AtTrx-h3. Heterologous expression of AtTrx-h2 in B. napus conferred salt tolerance with plants grown on 50 mM NaCl having higher fresh weight and chlorophyll contents compared with controls in hydroponic growth system. By contrast, expression of AtTrx-h3 or the empty vector control did not improve salt tolerance. In addition, AtTrx-h2-overexpressing transgenic plants exhibited lower levels of hydrogen peroxide and higher activities of antioxidant enzymes including peroxidase, catalase, and superoxide dismutase, compared with the plants expressing the empty vector control or AtTrx-h3. These results suggest that AtTrx-h2 is a promising candidate for engineering or breeding crops with enhanced salt stress tolerance.


Assuntos
Arabidopsis , Brassica napus , Regulação da Expressão Gênica de Plantas , Oxirredutases , Proteínas de Plantas , Tolerância ao Sal , Tiorredoxina h , Arabidopsis/enzimologia , Arabidopsis/genética , Oxirredutases/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Tiorredoxina h/genética
19.
BMC Plant Biol ; 20(1): 9, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906853

RESUMO

BACKGROUND: Zygophyllum is an important medicinal plant, with notable properties such as resistance to salt, alkali, and drought, as well as tolerance of poor soils and shifting sand. However, the response mechanism of Zygophyllum spp. to abiotic stess were rarely studied. RESULTS: Here, we aimed to explore the salt-tolerance genes of Zygophyllum plants by transcriptomic and metabolic approaches. We chose Z. brachypterum, Z. obliquum and Z. fabago to screen for salt tolerant and sensitive species. Cytological observation showed that both the stem and leaf of Z. brachypterum were significantly thicker than those of Z. fabago. Then, we treated these three species with different concentrations of NaCl, and found that Z. brachypterum exhibited the highest salt tolerance (ST), while Z. fabago was the most sensitive to salt (SS). With the increase of salt concentration, the CAT, SOD and POD activity, as well as proline and chlorophyll content in SS decreased significantly more than in ST. After salt treatment, the proportion of open stomata in ST decreased significantly more than in SS, although there was no significant difference in stomatal number between the two species. Transcriptomic analysis identified a total of 11 overlapping differentially expressed genes (DEGs) in the leaves and roots of the ST and SS species after salt stress. Two branched-chain-amino-acid aminotransferase (BCAT) genes among the 11 DEGs, which were significantly enriched in pantothenate and CoA biosynthesis, as well as the valine, leucine and isoleucine biosynthesis pathways, were confirmed to be significantly induced by salt stress through qRT-PCR. Furthermore, overlapping differentially abundant metabolites showed that the pantothenate and CoA biosynthesis pathways were significantly enriched after salt stress, which was consistent with the KEGG pathways enriched according to transcriptomics. CONCLUSIONS: In our study, transcriptomic and metabolomic analysis revealed that BCAT genes may affect the pantothenate and CoA biosynthesis pathway to regulate the salt tolerance of Zygophyllum species, which may constitute a newly identified signaling pathway through which plants respond to salt stress.


Assuntos
Coenzima A/metabolismo , Metaboloma/genética , Tolerância ao Sal/genética , Transcriptoma/genética , Zygophyllum , Coenzima A/genética , Perfilação da Expressão Gênica , Genes de Plantas , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/citologia , Raízes de Plantas/metabolismo , Estômatos de Plantas/citologia , Estômatos de Plantas/ultraestrutura , Transdução de Sinais/genética , Transaminases/genética , Transaminases/metabolismo , Zygophyllum/anatomia & histologia , Zygophyllum/genética , Zygophyllum/metabolismo
20.
Nat Commun ; 11(1): 186, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924762

RESUMO

Sodium (Na+) toxicity is one of the major damages imposed on crops by saline-alkaline stress. Here we show that natural maize inbred lines display substantial variations in shoot Na+ contents and saline-alkaline (NaHCO3) tolerance, and reveal that ZmNSA1 (Na+ Content under Saline-Alkaline Condition) confers shoot Na+ variations under NaHCO3 condition by a genome-wide association study. Lacking of ZmNSA1 promotes shoot Na+ homeostasis by increasing root Na+ efflux. A naturally occurred 4-bp deletion decreases the translation efficiency of ZmNSA1 mRNA, thus promotes Na+ homeostasis. We further show that, under saline-alkaline condition, Ca2+ binds to the EF-hand domain of ZmNSA1 then triggers its degradation via 26S proteasome, which in turn increases the transcripts levels of PM-H+-ATPases (MHA2 and MHA4), and consequently enhances SOS1 Na+/H+ antiporter-mediated root Na+ efflux. Our studies reveal the mechanism of Ca2+-triggered saline-alkaline tolerance and provide an important gene target for breeding saline-alkaline tolerant maize varieties.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Tolerância ao Sal/fisiologia , Sódio/metabolismo , Zea mays/fisiologia , Proteínas de Ligação ao Cálcio/genética , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Homeostase , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Tolerância ao Sal/genética , Cloreto de Sódio/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia , Zea mays/genética
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