Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.952
Filtrar
1.
An Acad Bras Cienc ; 93(3): e20200252, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34231757

RESUMO

Vuralia turcica (Fabaceae; Papilionoideae) is a critically endangered endemic plant species in Turkey. This plant grows naturally in saline environments, although the photosynthesis and physiological functions of many plants are affected by salt stress. Molecular control mechanisms and identification of genes involved in these mechanisms constitute the critical field of study in plant science. Trehalose-6-phosphate synthase (TPS) is one of the essential enzyme genes involved in trehalose biosynthesis, which is protective against salt stress. Also, the vacuolar Na+/H+ antiporter gene (NHX) is known to be useful in salt tolerance. In this study, the TPS and NHX-like genes in V. turcica were partially sequenced using degenerate primers for the first time and submitted to the NCBI database (accession numbers MK120983 and MH757417, respectively). Also, the expression levels of the genes encoding TPS and NHX were investigated. The results indicate that the increase in both the level of applied salt and cadmium is coupled with the increase in the expression level of NHX and TPS genes. However, salt exposure significantly affected the expression level of the NHX gene. The findings suggest that the NHX gene might play a crucial role in the salt tolerance ability of V. turcica.


Assuntos
Cádmio , Fabaceae , Cádmio/toxicidade , Fabaceae/metabolismo , Regulação da Expressão Gênica de Plantas , Glucosiltransferases , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Trocadores de Sódio-Hidrogênio/genética , Trocadores de Sódio-Hidrogênio/metabolismo , Turquia
2.
Nat Commun ; 12(1): 3380, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099714

RESUMO

Plant-parasitic nematodes (PPNs) are economically important pests of agricultural crops, and soybean cyst nematode (SCN) in particular is responsible for a large amount of damage to soybean. The need for new solutions for controlling SCN is becoming increasingly urgent, due to the slow decline in effectiveness of the widely used native soybean resistance derived from genetic line PI 88788. Thus, developing transgenic traits for controlling SCN is of great interest. Here, we report a Bacillus thuringiensis delta-endotoxin, Cry14Ab, that controls SCN in transgenic soybean. Experiments in C. elegans suggest the mechanism by which the protein controls nematodes involves damaging the intestine, similar to the mechanism of Cry proteins used to control insects. Plants expressing Cry14Ab show a significant reduction in cyst numbers compared to control plants 30 days after infestation. Field trials also show a reduction in SCN egg counts compared with control plants, demonstrating that this protein has excellent potential to control PPNs in soybean.


Assuntos
Toxinas de Bacillus thuringiensis/genética , Produtos Agrícolas/parasitologia , Resistência à Doença/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Soja/parasitologia , Tylenchoidea/patogenicidade , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis/metabolismo , Bioensaio , Caenorhabditis elegans , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Endotoxinas/metabolismo , Feminino , Engenharia Genética , Proteínas Hemolisinas/metabolismo , Melhoramento Vegetal/métodos , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/parasitologia , Soja/genética , Soja/metabolismo , Tylenchoidea/isolamento & purificação
3.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073522

RESUMO

For a long time, Cannabis sativa has been used for therapeutic and industrial purposes. Due to its increasing demand in medicine, recreation, and industry, there is a dire need to apply new biotechnological tools to introduce new genotypes with desirable traits and enhanced secondary metabolite production. Micropropagation, conservation, cell suspension culture, hairy root culture, polyploidy manipulation, and Agrobacterium-mediated gene transformation have been studied and used in cannabis. However, some obstacles such as the low rate of transgenic plant regeneration and low efficiency of secondary metabolite production in hairy root culture and cell suspension culture have restricted the application of these approaches in cannabis. In the current review, in vitro culture and genetic engineering methods in cannabis along with other promising techniques such as morphogenic genes, new computational approaches, clustered regularly interspaced short palindromic repeats (CRISPR), CRISPR/Cas9-equipped Agrobacterium-mediated genome editing, and hairy root culture, that can help improve gene transformation and plant regeneration, as well as enhance secondary metabolite production, have been highlighted and discussed.


Assuntos
Sistemas CRISPR-Cas , Cannabis , Edição de Genes , Plantas Geneticamente Modificadas , Agrobacterium , Cannabis/genética , Cannabis/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
4.
Ecotoxicol Environ Saf ; 220: 112407, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119926

RESUMO

2,4,6-trinitrotoluene (TNT) and cobalt (Co) contaminants have posed a severe environmental problem in many countries. Phytoremediation is an environmentally friendly technology for the remediation of these contaminants. However, the toxicity of TNT and cobalt limit the efficacy of phytoremediation application. The present research showed that expressing the Acidithiobacillus ferrooxidans single-strand DNA-binding protein gene (AfSSB) can improve the tolerance of Arabidopsis and tall fescue to TNT and cobalt. Compared to control plants, the AfSSB transformed Arabidopsis and tall fescue exhibited enhanced phytoremediation of TNT and cobalt separately contaminated soil and co-contaminated soil. The comet analysis revealed that the AfSSB transformed Arabidopsis suffer reduced DNA damage than control plants under TNT or cobalt exposure. In addition, the proteomic analysis revealed that AfSSB improves TNT and cobalt tolerance by strengthening the reactive superoxide (ROS) scavenging system and the detoxification system. Results presented here serve as strong theoretical support for the phytoremediation potential of organic and metal pollutants mediated by single-strand DNA-binding protein genes. SUMMARIZES: This is the first report that AfSSB enhances phytoremediation of 2,4,6-trinitrotoluene and cobalt separately contaminated and co-contaminated soil.


Assuntos
Cobalto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Poluentes do Solo/metabolismo , Trinitrotolueno/metabolismo , Acidithiobacillus/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Biodegradação Ambiental , Proteínas de Ligação a DNA/genética , Lolium/genética , Lolium/metabolismo , Plantas Geneticamente Modificadas/genética , Proteômica
5.
Ecotoxicol Environ Saf ; 220: 112406, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119927

RESUMO

Boron (B) excess gives rise to a serious agricultural problem. In this study, we identified a B toxicity responsive transcription factor AtWRKY47 in Arabidopsis thaliana. The T-DNA insertion mutants Atwrky47 showed enhanced tolerance to B toxicity with better growth parameters under high B conditions compared to wild-type Col-0 plants. Quantitative analysis of AtWRKY47 mRNA abundance indicated that it was down-regulated under B toxicity conditions. Fluorescently labeled AtWRKY47 protein was localized in nucleus. In contrast to the phenotype of Atwrky47 mutants, overexpression of AtWRKY47 in Col-0 background resulted in lower biomass, less chlorophyll content, and increased sensitivity to B toxicity. More importantly, the B concentration in shoots was higher in the overexpression lines and lower in the Atwrky47 mutants than in Col-0 plants, respectively. These results demonstrate that AtWRKY47 gene plays a key role in regulating plant tolerance to B toxicity.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Boro/metabolismo , Tolerância a Medicamentos , Fatores de Transcrição/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Boro/toxicidade , Tolerância a Medicamentos/genética , Regulação da Expressão Gênica de Plantas , Mutação , Fenótipo , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Fatores de Transcrição/genética
6.
Planta ; 254(1): 8, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34143292

RESUMO

MAIN CONCLUSION: OsJAZ11 regulates phosphate homeostasis by suppressing jasmonic acid signaling and biosynthesis in rice roots. Jasmonic Acid (JA) is a key plant signaling molecule which negatively regulates growth processes including root elongation. JAZ (JASMONATE ZIM-DOMAIN) proteins function as transcriptional repressors of JA signaling. Therefore, targeting JA signaling by deploying JAZ repressors may enhance root length in crops. In this study, we overexpressed JAZ repressor OsJAZ11 in rice to alleviate the root growth inhibitory action of JA. OsJAZ11 is a low phosphate (Pi) responsive gene which is transcriptionally regulated by OsPHR2. We report that OsJAZ11 overexpression promoted primary and seminal root elongation which enhanced Pi foraging. Expression studies revealed that overexpression of OsJAZ11 also reduced Pi starvation response (PSR) under Pi limiting conditions. Moreover, OsJAZ11 overexpression also suppressed JA signaling and biosynthesis as compared to wild type (WT). We further demonstrated that the C-terminal region of OsJAZ11 was crucial for stimulating root elongation in overexpression lines. Rice transgenics overexpressing truncated OsJAZ11ΔC transgene (i.e., missing C-terminal region) exhibited reduced root length and Pi uptake. Interestingly, OsJAZ11 also regulates Pi homeostasis via physical interaction with a key Pi sensing protein, OsSPX1. Our study highlights the functional connections between JA and Pi signaling and reveals JAZ repressors as a promising candidate for improving low Pi tolerance of elite rice genotypes.


Assuntos
Oryza , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Oxilipinas , Fosfatos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo
7.
Int J Mol Sci ; 22(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064885

RESUMO

Genetically modified (GM) crops possess some superior characteristics, such as high yield and insect resistance, but their biosafety has aroused broad public concern. Some genetic engineering technologies have recently been proposed to remove exogenous genes from GM crops. Few approaches have been applied to maintain advantageous traits, but excising exogenous genes in seeds or fruits from these hybrid crops has led to the generation of harvested food without exogenous genes. In a previous study, split-Cre mediated by split intein could recombine its structure and restore recombination activity in hybrid plants. In the current study, the recombination efficiency of split-Cre under the control of ovule-specific or pollen-specific promoters was validated by hybridization of transgenic Arabidopsis containing the improved expression vectors. In these vectors, all exogenous genes were flanked by two loxP sites, including promoters, resistance genes, reporter genes, and split-Cre genes linked to the reporter genes via LP4/2A. A gene deletion system was designed in which NCre was driven by proDD45, and CCre was driven by proACA9 and proDLL. Transgenic lines containing NCre were used as paternal lines to hybridize with transgenic lines containing CCre. Because this hybridization method results in no co-expression of the NCre and CCre genes controlled by reproduction-specific promoters in the F1 progeny, the desirable characteristics could be retained. After self-crossing in F1 progeny, the expression level and protein activity of reporter genes were detected, and confirmed that recombination of split-Cre had occurred and the exogenous genes were partially deleted. The gene deletion efficiency represented by the quantitative measurements of GUS enzyme activity was over 59%, with the highest efficiency of 73% among variable hybrid combinations. Thus, in the present study a novel dual reproductive cell-specific promoter-mediated gene deletion system was developed that has the potential to take advantage of the merits of GM crops while alleviating biosafety concerns.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Deleção de Genes , Integrases/metabolismo , Plantas Geneticamente Modificadas/genética , Regiões Promotoras Genéticas , Transgenes , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Engenharia Genética , Vetores Genéticos , Integrases/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Recombinação Genética , Reprodução
8.
Int J Mol Sci ; 22(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34073055

RESUMO

Plant proline-rich proteins (PRPs) are cell wall proteins that occur in the plant kingdom and are involved in plant development and stress response. In this study, 9 PRP genes were identified from the apple genome and a comprehensive analysis of the PRP family was conducted, including gene structures, phylogenetic analysis, chromosome mapping, and so on. The expression of MdPRPs varied among tissues and in response to different types of stresses. MdPRP4 and MdPRP7 were induced by five detected stress treatments, including heat, drought, abscisic acid, cold, and salt; the expression patterns of the others varied under different types of stress. Subcellular localization showed that MdPRPs mainly functioned in the cytoplasm, except for MdPRP1 and MdPRP5, which also functioned in the nucleus. When MdPRP6 was overexpressed in tobacco, the transgenic plants showed higher tolerance to high temperature (48 °C) compared with wild-type (WT) plants. The transgenic plants showed milder wilting, a lower accumulation of electrolyte leakage, MDA and ROS, and a higher level of chlorophyll and SOD and POD activity, indicating that MdPRP6 may be an important gene in apples for heat stress tolerance. Overall, this study suggested that MdPRPs are critically important for the ability of apple responses to stresses.


Assuntos
Malus/genética , Proteínas de Plantas , Domínios Proteicos Ricos em Prolina , Estresse Fisiológico , Temperatura Alta , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tabaco/genética , Tabaco/metabolismo
9.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069397

RESUMO

Drought stress is a major constraint in global maize production, causing almost 30-90% of the yield loss depending upon growth stage and the degree and duration of the stress. Here, we report that ectopic expression of Arabidopsis glutaredoxin S17 (AtGRXS17) in field grown maize conferred tolerance to drought stress during the reproductive stage, which is the most drought sensitive stage for seed set and, consequently, grain yield. AtGRXS17-expressing maize lines displayed higher seed set in the field, resulting in 2-fold and 1.5-fold increase in yield in comparison to the non-transgenic plants when challenged with drought stress at the tasseling and silking/pollination stages, respectively. AtGRXS17-expressing lines showed higher relative water content, higher chlorophyll content, and less hydrogen peroxide accumulation than wild-type (WT) control plants under drought conditions. AtGRXS17-expressing lines also exhibited at least 2-fold more pollen germination than WT plants under drought stress. Compared to the transgenic maize, WT controls accumulated higher amount of proline, indicating that WT plants were more stressed over the same period. The results present a robust and simple strategy for meeting rising yield demands in maize under water limiting conditions.


Assuntos
Glutarredoxinas/genética , Glutarredoxinas/metabolismo , Estresse Fisiológico/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Secas , Expressão Ectópica do Gene/genética , Grão Comestível/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Estresse Fisiológico/fisiologia , Termotolerância/genética , Zea mays/genética
10.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069632

RESUMO

In tobacco, the efficiency of Zn translocation to shoots depends on Zn/Cd status. Previous studies pointed to the specific contribution of root parts in the regulation of this process, as well as the role of NtZIP4A/B (from the ZIP family; Zrt Irt-like Proteins). Here, to verify this hypothesis, NtZIP4A/B RNAi lines were generated. Then, in plants exposed to combinations of Zn and Cd concentrations in the medium, the consequences of NtZIP4A/B suppression for the translocation of both metals were determined. Furthermore, the apical, middle, and basal root parts were examined for accumulation of both metals, for Zn localization (using Zinpyr-1), and for modifications of the expression pattern of ZIP genes. Our results confirmed the role of NtZIP4A/B in the control of Zn/Cd-status-dependent transfer of both metals to shoots. Furthermore, they indicated that the middle and basal root parts contributed to the regulation of this process by acting as a reservoir for excess Zn and Cd. Expression studies identified several candidate ZIP genes that interact with NtZIP4A/B in the root in regulating Zn and Cd translocation to the shoot, primarily NtZIP1-like in the basal root part and NtZIP2 in the middle one.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Tabaco/metabolismo , Zinco/metabolismo , Adenosina Trifosfatases/metabolismo , Transporte Biológico/genética , Cádmio/metabolismo , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica de Plantas/genética , Homeostase , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tabaco/genética
11.
Plant Physiol Biochem ; 164: 279-288, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34020168

RESUMO

Tree peony (Paeonia suffruticosa Andr.) is a well-known ornamental flower in China with diverse colors. Flower color is one of the most important economic characteristics of tree peony and is mainly determined by anthocyanins. In this study, we cloned a PsMYB58 gene, which contained a 654 bp open reading frame (ORF), encoding a polypeptide of 218 amino acids. Sequence and phylogenetic analysis indicated that PsMYB58 is an anthocyanin regulatory R2R3-MYB gene. The transcription levels of PsMYB58 in different developmental stages of tree peony flowers were similar to those of the anthocyanin biosynthetic genes PsCHS, PsCHI, PsDFR, and PsANS. A bimolecular fluorescence complementation assay showed that PsMYB58 interacted with PsbHLH1 and PsbHLH3 in vivo. The overexpression of PsMYB58 in tobacco enhanced anthocyanin accumulation in various organs. Comparative transcriptome analysis showed that 943 genes were upregulated and 1203 downregulated in PsMYB58 transgenic tobacco, among which genes involved in the anthocyanin pathway were positively activated. Real-time quantitative PCR analysis verified that anthocyanin biosynthetic genes, including NtCHS, NtCHI, NtF3H, NtF3'H, NtDFR, and NtANS, and an anthocyanin regulatory bHLH gene, NtAN1b, were significantly upregulated in PsMYB58 transgenic tobacco. Our results indicated that PsMYB58 is a positive anthocyanin regulator in tree peony flowers. In summary, the functional identification of PsMYB58 furthers our understanding of the mechanism of peony flower color formation, thus providing a foundation for flower color improvement and molecular breeding.


Assuntos
Paeonia , Antocianinas , China , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Genes myb , Paeonia/genética , Paeonia/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
12.
Plant Sci ; 308: 110920, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34034870

RESUMO

Artemisinin is a secondary metabolite extracted from Artemisia annua. As an effective antimalarial component certified by WHO, artemisinin has extensive economical values. Numerous studies about transcription factors positively regulating artemisinin biosynthesis have been published while negative regulators are rarely reported. In the present study, we identified AaMYB15 as the first R2R3-MYB that negatively regulates artemisinin biosynthesis in A. annua. Experimental evidences showed that AaMYB15 is a transcription factor within nucleus and predominantly expressed in glandular secretory trichomes (GSTs) in A. annua where artemisinin is synthesized and accumulated. The expression of AaMYB15 was induced by dark and JA treatment. Overexpression of AaMYB15 led to a significant decline in the expression levels of key enzyme genes ADS, CYP, DBR2, and ALDH1 and a significant decrease in the artemisinin contents of transgenic A. annua. AaMYB15 directly bound to the promoter of AaORA, a reported positive regulator of artemisinin biosynthesis in JA signaling pathway, to repress its transcriptional activity, thus downregulating the expression levels of downstream key enzyme genes and negatively regulating the artemisinin biosynthesis. Our study provides candidate gene for improvement of A. annua germplasm and new insights into the artemisinin biosynthesis regulation network mediated by light and JA.


Assuntos
Artemisia annua/genética , Artemisininas/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Artemisia annua/metabolismo , Vias Biossintéticas/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regiões Promotoras Genéticas , Alinhamento de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
13.
Toxins (Basel) ; 13(5)2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946742

RESUMO

Fusarium graminearum, the causal agent of Fusarium head blight (FHB), produces trichothecenes including deoxynivalenol (DON), nivalenol (NIV), and 3,7,15-trihydroxy-12,13-epoxytrichothec-9-ene (NX-3). These toxins contaminate grains and cause profound health problems in humans and animals. To explore exploiting a fungal self-protection mechanism in plants, we examined the ability of F. graminearum trichothecene 3-O-acetyltransferase (FgTri101) to detoxify several key trichothecenes produced by F. graminearum: DON, 15-ADON, NX-3, and NIV. FgTri101 was cloned from F. graminearum and expressed in Arabidopsis plants. We compared the phytotoxic effects of purified DON, NIV, and NX-3 on the root growth of transgenic Arabidopsis expressing FgTri101. Compared to wild type and GUS controls, FgTri101 transgenic Arabidopsis plants displayed significantly longer root length on media containing DON and NX-3. Furthermore, we confirmed that the FgTri101 transgenic plants acetylated DON to 3-ADON, 15-ADON to 3,15-diADON, and NX-3 to NX-2, but did not acetylate NIV. Approximately 90% of the converted toxins were excreted into the media. Our study indicates that transgenic Arabidopsis expressing FgTri101 can provide plant protection by detoxifying trichothecenes and excreting the acetylated toxins out of plant cells. Characterization of plant transporters involved in trichothecene efflux will provide novel targets to reduce FHB and mycotoxin contamination in economically important plant crops.


Assuntos
Acetiltransferases/metabolismo , Fusarium/genética , Tricotecenos/metabolismo , Acetilação , Acetiltransferases/genética , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/metabolismo , Clonagem Molecular , Fusarium/enzimologia , Fusarium/metabolismo , Inativação Metabólica/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plântula/metabolismo
14.
Plant Physiol Biochem ; 165: 1-9, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34029940

RESUMO

Stress associated proteins (SAPs), a class of A20/AN1 zinc finger domain-containing proteins, are involved in a variety of biotic and abiotic stress responses in plants. However, little is known about the SAP gene family and their functions in Tamarix hispida. In this study, we isolated and characterized 11 SAPs from T. hispida. The expression patterns of ThSAPs were analyzed under various stresses (salt and drought) and phytohormone treatment (SA, ABA and MeJA) using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR). Most ThSAPs exhibited transcriptional responses to abiotic stresses and phytohormones. Among these ThSAPs, ThSAP6 was significantly induced by salt stress. Gain-and loss-of-function analyses revealed that ThSAP6 was a positive regulator of salt stress response. Overexpression of ThSAP6 in T. hispida increased antioxidant enzymes activity and proline content and decreased reactive oxygen species (ROS) accumulation and cell membrane damage under salt stress, while the opposite physiological changes were observed in ThSAP6-RNAi (RNA interference) lines. This study provides a comprehensive description of the SAP gene family in T. hispida, and demonstrates that ThSAP6 is a potential candidate for biotechnological approaches to improve salt tolerance in plants.


Assuntos
Tamaricaceae , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Tamaricaceae/genética , Tamaricaceae/metabolismo
15.
Plant Physiol Biochem ; 165: 104-113, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34034156

RESUMO

Calcium-dependent protein kinases (CDPKs) are Ca2+ decoders in plants. AtCPK1 is a positive regulator in the plant response to biotic and abiotic stress. Inactivation of the autoinhibitory domain of AtCPK1 in the mutated form KJM23 provides constitutive activity of the kinase. In the present study, we investigated the effect of overexpressed native and mutant KJM23 forms on salinity tolerance in Nicotiana tabacum. Overexpression of native AtCPK1 provided tobacco resistance to 120 mM NaCl during germination and 180 mM NaCl during long-term growth, while the resistance of plants increased to 240 mM NaCl during both phases of plant development when transformed with KJM23. Mutation in the junction KJM4, which disrupted Ca2+ induced activation, completely nullified the acquired salt tolerance up to levels of normal plants. Analysis by confocal microscopy showed that under high salinity conditions, overexpression of AtCPK1 and KJM23 inhibited reactive oxygen species (ROS) accumulation to levels observed in untreated plants. Quantitative real-time PCR analysis showed that overexpression of AtCPK1 and KJM23 was associated with changes in expression of genes encoding heat shock factors. In all cases, the KJM23 mutation enhanced the effect of AtCPK1, while the KJM4 mutation reduced it to the control level. We suggest that the autoinhibitory domains in CDPKs could be promising targets for manipulation in engineering salt-tolerant plants.


Assuntos
Tolerância ao Sal , Tabaco , Regulação da Expressão Gênica de Plantas , Mutação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Tabaco/genética , Tabaco/metabolismo
16.
Plant Physiol Biochem ; 165: 80-93, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34034163

RESUMO

The Coffea arabica HB12 gene (CaHB12), which encodes a transcription factor belonging to the HD-Zip I subfamily, is upregulated under drought, and its constitutive overexpression (35S:CaHB12OX) improves the Arabidopsis thaliana tolerance to drought and salinity stresses. Herein, we generated transgenic cotton events constitutively overexpressing the CaHB12 gene, characterized these events based on their increased tolerance to water deficit, and exploited the gene expression level from the CaHB12 network. The segregating events Ev8.29.1, Ev8.90.1, and Ev23.36.1 showed higher photosynthetic yield and higher water use efficiency under severe water deficit and permanent wilting point conditions compared to wild-type plants. Under well-irrigated conditions, these three promising transformed events showed an equivalent level of Abscisic acid (ABA) and decreased Indole-3-acetic acid (IAA) accumulation, and a higher putrescine/(spermidine + spermine) ratio in leaf tissues was found in the progenies of at least two transgenic cotton events compared to non-transgenic plants. In addition, genes that are considered as modulated in the A. thaliana 35S:CaHB12OX line were also shown to be modulated in several transgenic cotton events maintained under field capacity conditions. The upregulation of GhPP2C and GhSnRK2 in transgenic cotton events maintained under permanent wilting point conditions suggested that CaHB12 might act enhancing the ABA-dependent pathway. All these data confirmed that CaHB12 overexpression improved the tolerance to water deficit, and the transcriptional modulation of genes related to the ABA signaling pathway or downstream genes might enhance the defense responses to drought. The observed decrease in IAA levels indicates that CaHB12 overexpression can prevent leaf abscission in plants under or after stress. Thus, our findings provide new insights on CaHB12 gene and identify several promising cotton events for conducting field trials on water deficit tolerance and agronomic performance.


Assuntos
Secas , Gossypium , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Gossypium/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Plant Physiol Biochem ; 165: 147-160, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34038811

RESUMO

S-adenosylmethionine decarboxylase (SAMDC) mediates the biosynthesis of polyamines (PAs) and plays a positive role in plants' response to adversity stress tolerance. In this study, we isolated a SAMDC gene from white clover, which is located in mitochondria. It was strongly induced when white clover exposed to drought (15% PEG6000), salinity (200 mM NaCl), 20 µM spermidine, 100 µM abscisic acid, and 10 mM H2O2, especially in leaves. The INVSc1 yeast introduced with TrSAMDC1 had tolerance to drought, salt, and oxidative stress. Overexpression of TrSAMDC1 in Arabidopsis showed higher fresh weight and dry weight under drought and salt treatment and without growth inhibition under normal conditions. Leaf senescence induced by drought and saline was further delayed in transgenic plants, regardless of cultivation in 1/2 MS medium and soil. During drought and salt stress, transgenic plants exhibited a significant increase in relative water content, maximum photosynthesis efficiency (Fv/Fm), performance index on the absorption basis (PIABS), activities of antioxidant protective enzymes such as SOD, POD, CAT, and APX, and a significant decrease in accumulation of MDA and H2O2 as compared to the WT. The concentrations of total PAs, putrescine, spermidine, and spermidine in transgenic lines were higher in transgenic plants than in WT under normal and drought conditions. These results suggested that TrSAMDC1 could effectively mitigate abiotic stresses without the expense of production and be a potential candidate gene for improving the drought and salt resistance of crops.


Assuntos
Arabidopsis , Secas , Arabidopsis/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio , Medicago/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética
18.
Plant Physiol Biochem ; 164: 44-53, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33962230

RESUMO

The APETAL2/Ethylene Responsive Factor (AP2/ERF) family was the subject of intensive research which led to the identification of several members involved in different stress responses such as salinity, drought and high temperature. The SHN/WIN clade of AP2/ERF participates in many important processes such as cutin and wax biosynthesis, ethylene signaling and gene expression. Here, we report the functional analysis of SHN1-type transcription factor, HvSHN1, from barely. The overexpression of HvSHN1 under the control of the duplicated 35S promoter in transgenic tobacco plants improved tolerance to salt, water stress and heat stress. Transgenic lines exhibited altered permeability of the cuticle and decreased stomatal density. Under heat stress, HvSHN1 transgenic lines exhibited higher superoxide dismutase (SOD) and catalase (CAT) activity and lower MDA and H2O2 contents than did WT. The overexpression of HvSHN1 upregulated different genes involved in osmotic stress, oxidative stress, sugar metabolism, and wax biosynthesis. To understand the involvement of HvSHN1 in heat stress tolerance, promoter regions of two tobacco genes homologous to Arabidopsis genes HSP90.1 and RAP2.6 were analyzed and DRE cis-elements; binding sites of HvSHN1, were found. Interaction network of HvSHN1, predicted using STRING software, contained proteins with predicted functions related to lipids metabolism and a gene encoding Cyclin-Dependent Kinase. These results suggest that HvSHN1 is an interesting candidate for the improvement of abiotic stress tolerance especially in the context of climate change.


Assuntos
Hordeum , Tolerância ao Sal , Secas , Regulação da Expressão Gênica de Plantas , Hordeum/metabolismo , Peróxido de Hidrogênio , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Tabaco/genética , Tabaco/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Plant Physiol Biochem ; 164: 205-221, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34004558

RESUMO

Plant monovalent cation/proton antiporters (CPAs), types of transmembrane transporters, play important roles in resistance to salt stress. In this study, 37 CPA genes from moso bamboo (Phyllostachys edulis) were identified and characterised. The expression profiles of 10 CPA1 genes (PheNHXs) of moso bamboo were detected by qRT-PCR, which showed that they were specifically expressed in six tissues. In addition, the expression of 10 PheNHXs in leaves and roots changed significantly under 150/200 mM NaCl and 100 µM ABA treatments. In particular, the expression of PheNHX2 in leaves and roots was significantly upregulated under NaCl treatment, thus, we cloned PheNHX2 and analysed its function. Subcellular localisation analysis showed that PheNHX2 was located on the vacuolar membrane. Overexpression of PheNHX2 reduced seed germination and root growth of Arabidopsis thaliana under salt stress, as well as severely affecting cellular Na+ and K+ content, which in turn reduced the salt tolerance of transgenic Arabidopsis. Measurements of physiological indicators, including chlorophyll content, malondialdehyde content, peroxidase and catalase enzyme activities and relative electrical conductivity, all supported this conclusion. Under salt stress, PheNHX2 also inhibited the expression of some stress-related and ion transport-related genes in transgenic Arabidopsis. Overall, these results indicate that overexpression of PheNHX2 reduces the salt tolerance of transgenic Arabidopsis. This investigation establishes a foundation for subsequent functional studies of moso bamboo CPA genes, and it provides a deeper understanding of PheNHX2 regulation in relation to the salt tolerance of moso bamboo.


Assuntos
Arabidopsis , Antiporters/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Cátions Monovalentes , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Poaceae/genética , Poaceae/metabolismo , Prótons
20.
Planta ; 253(6): 122, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34003383

RESUMO

MAIN CONCLUSION: The rice OsFAH gene functions identically to that of Arabidopsis SSCD1 encoding FAH. Loss of OsFAH causes rice sterility. Fumarylacetoacetate hydrolase (FAH) is the last enzyme in the tyrosine (Tyr) degradation pathway that is crucial for animals. By genetic analysis of the mutant of Short-day Sensitive Cell Death 1 gene encoding Arabidopsis FAH, we first found the pathway also plays a critical role in plants (Han et al., Plant Physiol 162:1956-1964, 2013). To further understand the role of the Tyr degradation pathway in plants, we investigated a biological function of the rice FAH. Firstly, the cDNA of rice FAH gene (OsFAH) was cloned and confirmed to be able to rescue the Arabidopsis Short-day Sensitive Cell Death 1 mutant defective in the FAH. Then, we identified the OsFAH T-DNA insertion mutant and generated the OsFAH RNA interference lines, and found that loss of OsFAH results in rice sterility. Furthermore, we analyzed expression of the OsFAH gene in roots, stems, leaves and young panicles at booting stage of rice and found that its transcript level was highest in young panicles and lowest in roots. In addition, the expression analysis of ß-glucuronidase driven by OsFAH promoter in transgenic Arabidopsis showed that the OsFAH promoter was highly active in aerial tissues in vegetative stage, and sepals, filaments and stigma in reproductive stage. These results suggested that FAH plays an important role in rice fertility.


Assuntos
Arabidopsis , Oryza , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Fertilidade , Regulação da Expressão Gênica de Plantas , Hidrolases/genética , Hidrolases/metabolismo , Oryza/genética , Oryza/metabolismo , Plantas Geneticamente Modificadas/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...