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1.
Plant Cell Environ ; 47(7): 2578-2596, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38533652

RESUMO

Enhancing carbohydrate export from source to sink tissues is considered to be a realistic approach for improving photosynthetic efficiency and crop yield. The rice sucrose transporters OsSUT1, OsSWEET11a and OsSWEET14 contribute to sucrose phloem loading and seed filling. Crucially, Xanthomonas oryzae pv. oryzae (Xoo) infection in rice enhances the expression of OsSWEET11a and OsSWEET14 genes, and causes leaf blight. Here we show that co-overexpression of OsSUT1, OsSWEET11a and OsSWEET14 in rice reduced sucrose synthesis and transport leading to lower growth and yield but reduced susceptibility to Xoo relative to controls. The immunity-related hypersensitive response (HR) was enhanced in the transformed lines as indicated by the increased expression of defence genes, higher salicylic acid content and presence of HR lesions on the leaves. The results suggest that the increased expression of OsSWEET11a and OsSWEET14 in rice is perceived as a pathogen (Xoo) attack that triggers HR and results in constitutive activation of plant defences that are related to the signalling pathways of pathogen starvation. These findings provide a mechanistic basis for the trade-off between plant growth and immunity because decreased susceptibility against Xoo compromised plant growth and yield.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras , Oryza , Doenças das Plantas , Imunidade Vegetal , Proteínas de Plantas , Plantas Geneticamente Modificadas , Ácido Salicílico , Sacarose , Xanthomonas , Oryza/microbiologia , Oryza/genética , Oryza/imunologia , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Xanthomonas/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Sacarose/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Membrana Transportadoras/genética , Ácido Salicílico/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/imunologia
2.
Biochem Biophys Res Commun ; 662: 135-141, 2023 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-37119729

RESUMO

Ascorbate (AsA) is a crucial antioxidant in plants, and its recycling is necessary for protecting cells from oxidative damage and imparting stress tolerance. The monodehydroascorbate reductase (MDHAR) enzyme of the ascorbate-glutathione pathway plays a vital role in recycling AsA from monodehydroascorbate (MDHA) radical. Pennisetum glaucum (Pg), also known as pearl millet, is known to be more tolerant to abiotic stress than other food crops, such as rice. However, the contribution of MDHAR from this sessile plant to its unique stress tolerance mechanism is not well understood. In this study, we isolated a gene encoding the MDHAR enzyme from heat stress-adapted pearl millet and characterized it using enzyme kinetics, thermal stability assays, and crystal structure determination. Our results indicate that PgMDHAR is a more robust enzyme than its rice counterpart (Oryza sativa; Os). We solved the crystal structure of PgMDHAR at 1.8 Å and found that the enzyme has a more compact structure and greater stability than OsMDHAR. Using hybrid quantum mechanics and molecular mechanics calculations, we demonstrate that the structure of PgMDHAR contributes to increased stability towards bound FAD. Overall, the higher structural stability and affinity for NADH demonstrated by PgMDHAR are expected to impart improved stress tolerance. Our findings suggest that transgenic food crops expressing MDHAR from stress-adapted pearl millet may exhibit better tolerance to oxidative stress in the unpredictable climatic conditions prevalent today.


Assuntos
Pennisetum , Ácido Ascórbico/metabolismo , Ácido Desidroascórbico/metabolismo
3.
Eur Respir J ; 61(3)2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36517177

RESUMO

This expert group consensus statement emphasises the need for standardising the definition of progressive fibrosing interstitial lung diseases (F-ILDs), with an accurate initial diagnosis being of paramount importance in ensuring appropriate initial management. Equally, case-by-case decisions on monitoring and management are essential, given the varying presentations of F-ILDs and the varying rates of progression. The value of diagnostic tests in risk stratification at presentation and, separately, the importance of a logical monitoring strategy, tailored to manage the risk of progression, are also stressed. The term "progressive pulmonary fibrosis" (PPF) exactly describes the entity that clinicians often face in practice. The importance of using antifibrotic therapy early in PPF (once initial management has failed to prevent progression) is increasingly supported by evidence. Artificial intelligence software for high-resolution computed tomography analysis, although an exciting tool for the future, awaits validation. Guidance is provided on pulmonary rehabilitation, oxygen and the use of non-invasive ventilation focused specifically on the needs of ILD patients with progressive disease. PPF should be differentiated from acute deterioration due to drug-induced lung toxicity or other forms of acute exacerbations. Referral criteria for a lung transplant are discussed and applied to patient needs in severe diseases where transplantation is not realistic, either due to access limitations or transplantation contraindications. In conclusion, expert group consensus guidance is provided on the diagnosis, treatment and monitoring of F-ILDs with specific focus on the recognition of PPF and the management of pulmonary fibrosis progressing despite initial management.


Assuntos
Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Fibrose Pulmonar , Humanos , Fibrose Pulmonar/diagnóstico , Fibrose Pulmonar/terapia , Inteligência Artificial , Progressão da Doença , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/terapia , Fibrose , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/terapia
4.
Arch Biochem Biophys ; 741: 109603, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37084805

RESUMO

Plant dehydroascorbate reductases (DHARs) are only known as soluble antioxidant enzymes of the ascorbate-glutathione pathway. They recycle ascorbate from dehydroascorbate, thereby protecting plants from oxidative stress and the resulting cellular damage. DHARs share structural GST fold with human chloride intracellular channels (HsCLICs) which are dimorphic proteins that exists in soluble enzymatic and membrane integrated ion channel forms. While the soluble form of DHAR has been extensively studied, the existence of a membrane integrated form remains unknown. We demonstrate for the first time using biochemistry, immunofluorescence confocal microscopy, and bilayer electrophysiology that Pennisetum glaucum DHAR (PgDHAR) is dimorphic and is localized to the plant plasma membrane. In addition, membrane translocation increases under induced oxidative stress. Similarly, HsCLIC1 translocates more into peripheral blood mononuclear cells (PBMCs) plasma membrane under induced oxidative stress conditions. Moreover, purified soluble PgDHAR spontaneously inserts and conducts ions in reconstituted lipid bilayers, and the addition of detergent facilitates insertion. In addition to the well-known soluble enzymatic form, our data provides conclusive evidence that plant DHAR also exists in a novel membrane-integrated form. Thus, the structure of DHAR ion channel form will help gain deeper insights into its function across various life forms.


Assuntos
Leucócitos Mononucleares , Oxirredutases , Humanos , Oxirredutases/metabolismo , Oxirredução , Ácido Ascórbico/metabolismo , Estresse Oxidativo , Glutationa/metabolismo , Canais Iônicos/metabolismo
5.
J Assoc Physicians India ; 71(7): 11-12, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37449695

RESUMO

Cough is the body's reflex when the throat or airway is irritated by a foreign body, such as irritants, microbes, and fluids. Cough caused due to a disorder or infection can last for a few days to a couple of weeks and is usually self-limiting and self-resolving. However, in certain cases, cough can persist for months, disrupting everyday activities, affecting the patient's mental health, and causing pain and fatigue. There are a number of different therapeutic strategies to manage acute and chronic cough, depending on the cause. Dry cough can be treated using opioids, nonopioids, antitussives, and antihistamines. Expectorants and mucolytics are widely used in the management of productive cough. The underlying cause of cough should be appropriately managed with specific therapy. The choice of treatment regimen is dependent on the patient's medical history, symptoms, and preexisting conditions. Based on the literature review and clinical practice, a comprehensive approach to the management of cough as a symptom has been proposed.


Assuntos
Antitussígenos , Tosse , Humanos , Antitussígenos/uso terapêutico , Doença Crônica , Tosse/diagnóstico , Tosse/etiologia , Tosse/terapia , Expectorantes/uso terapêutico , Atenção Primária à Saúde , Guias como Assunto
6.
Pestic Biochem Physiol ; 182: 105026, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35249642

RESUMO

In rice farming, the blast disease caused by Magnaporthe oryzae (T.T. Hebert) M.E. Barr. is one of the primary production constraints worldwide. The current blast management options such as blast-resistant varieties and spraying fungicides are neither durable nor commercially and environmentally compatible. In the present study, we investigated the antifungal and defense elicitor activity of potassium phosphite (Phi) against M. oryzae on elite rice cultivar BPT5204 (popularly known as Samba Mahsuri in India) and its transgenic rice variant (ptxD-OE) over-expressing a phosphite dehydrogenase enzyme. The Phi was evaluated both preventively and curatively on rice genotypes where the preventive spray of Phi outperformed the Phi curative application with significant reductions in both rice blast severity (35.67-60.49%) and incidence (22.27-53.25%). Moreover, the application of Phi increased the levels of photosynthetic pigments (Chlorophyll and Carotenoids) coupled with increased activity of defense enzymes (PAL, SOD, and APx). Besides, Phi application also induced the expression of defense-associated genes (OsCEBiP and OsPDF2.2) in the rice leaf. Furthermore, the Phi application reduced the reactive Malondialdehyde (lipid peroxidation) to minimize the cellular damage incited by Magnaporthe in rice. Overall, the present study showed the potential of Phi for blast suppression on rice as an alternative to the current excessive use of toxic fungicides.


Assuntos
Magnaporthe , Oryza , Antifúngicos , Oryza/genética , Oryza/microbiologia , Fosfitos , Doenças das Plantas/microbiologia , Compostos de Potássio
7.
Plant Biotechnol J ; 18(12): 2504-2519, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32516520

RESUMO

Glyphosate is a popular, systemic, broad-spectrum herbicide used in modern agriculture. Being a structural analog of phosphoenolpyruvate (PEP), it inhibits 5-enolpyruvylshikimate 3-phosphate synthase (EPSPS) which is responsible for the biosynthesis of aromatic amino acids and various aromatic secondary metabolites. Taking a lead from glyphosate-resistant weeds, two mutant variants of the rice EPSPS gene were developed by amino acid substitution (T173I + P177S; TIPS-OsEPSPS and G172A + T173I + P177S; GATIPS-OsEPSPS). These mutated EPSPS genes were overexpressed in rice under the control of either native EPSPS or constitutive promoters (maize ubiquitin [ZmUbi] promoter). The overexpression of TIPS-OsEPSPS under the control of the ZmUbi promoter resulted in higher tolerance to glyphosate (up to threefold of the recommended dose) without affecting the fitness and related agronomic traits of plants in both controlled and field conditions. Furthermore, such rice lines produced 17%-19% more grains compared to the wild type (WT) in the absence of glyphosate application and the phenylalanine and tryptophan contents in the transgenic seeds were found to be significantly higher in comparison with WT seeds. Our results also revealed that the native promoter guided expression of modified EPSPS genes did not significantly improve the glyphosate tolerance. The present study describing the introduction of a crop-specific TIPS mutation in class I aroA gene of rice and its overexpression have potential to substantially improve the yield and field level glyphosate tolerance in rice. This is the first report to observe that the EPSPS has role to play in improving grain yield of rice.


Assuntos
Herbicidas , Oryza , 3-Fosfoshikimato 1-Carboxiviniltransferase/genética , Glicina/análogos & derivados , Glicina/farmacologia , Resistência a Herbicidas/genética , Herbicidas/farmacologia , Oryza/genética , Fosfatos , Glifosato
8.
J Cell Biochem ; 120(10): 18104-18116, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31172606

RESUMO

Triple-negative breast cancer (TNBC) is the most outrageous subtype of breast cancer. Emphasizing the urge of new approach in cancer therapy, combinational drug therapy may be proven as an effective strategy. In our previous study, we reported that coralyne (COR) with paclitaxel (PTX) efficiently decreases the proliferation of MDA-MB-231 compared with MCF-7 cell line. Thus, we studied the effect of COR and PTX in combination on apoptosis of MDA-MB-231 cell line. In silico results demonstrated that COR intercalates DNA at a minor groove. In vitro approaches revealed that in combination (COR and PTX) increases the efficacy of apoptosis in MDA-MB-231 cell line by a significant increase in G1/S phase arrest, DNA fragmentation, and change in mitochondria membrane potential. The expression of ATM and ATR a serine/threonine-protein kinase, ataxia telangiectasia and Rad3-related protein were depleted with an increase in time from 24 to 48 hours in concurrent with increased levels of γH2AX indicating that DNA damage routes cells to enter apoptosis. This was confirmed by high levels of caspase-3 and cytochrome c. Also, the decrease in the expression levels of matrix metalloproteinase-9 confirmed the antimetastatic efficacy of COR + PTX. The present study indicates that the synergistic effect of COR and PTX can enhance apoptosis in MDA-MB-231 cell line and may be proven as a potential anticancer therapy against TNBC.


Assuntos
Apoptose/efeitos dos fármacos , Alcaloides de Berberina/farmacologia , Paclitaxel/farmacologia , Neoplasias de Mama Triplo Negativas/genética , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Alcaloides de Berberina/administração & dosagem , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Dano ao DNA , Fragmentação do DNA/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Paclitaxel/administração & dosagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo
9.
Plant Mol Biol ; 94(6): 595-607, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28634865

RESUMO

KEY MESSAGE: The topoisomerase II expression varies as a function of cell proliferation. Maximal topoisomerase II expression was tightly coupled to S phase and G2/M phase via both transcriptional and post-transcriptional regulation. Investigation in meiosis using pollen mother cells also revealed that it is not the major component of meiotic chromosomes, it seems to diffuse out once meiotic chromosomal condensation is completed. Synchronized tobacco BY-2 cell cultures were used to study the role of topoisomerase II in various stages of the cell cycle. Topoisomerase II transcript accumulation was observed during the S- and G2/M- phase of cell cycle. This biphasic expression pattern indicates the active requirement of topoisomerase II during these stages of the cell cycle. Through immuno-localization of topoisomerase II was observed diffusely throughout the nucleoplasm in interphase nuclei, whereas, the nucleolus region exhibited a more prominent immuno-positive staining that correlated with rRNA transcription, as shown by propidium iodide staining and BrUTP incorporation. The immuno-staining analysis also showed that topoisomerase II is the major component of mitotic chromosomes and remain attached to the chromosomes during cell division. The inhibition of topoisomerase II activity using specific inhibitors revealed quite dramatic effect on condensation of chromatin and chromosome individualization from prophase to metaphase transition. Partially condensed chromosomes were not arranged on metaphase plate and chromosomal perturbations were observed when advance to anaphase, suggesting the importance of topoisomerase II activity for proper chromosome condensation and segregation during mitosis. Contrary, topoisomerase II is not the major component of meiotic chromosomes, even though mitosis and meiosis share many processes, including the DNA replication, chromosome condensation and precisely regulated partitioning of chromosomes into daughter cells. Even if topoisomerase II is required for individualization and condensation of meiotic chromosomes, it seems to diffuse out once meiotic chromosomal condensation is completed.


Assuntos
Ciclo Celular/fisiologia , Segregação de Cromossomos , DNA Topoisomerases Tipo II/metabolismo , Mitose , Nicotiana/citologia , Nucléolo Celular/genética , Nucléolo Celular/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Replicação do DNA , DNA Topoisomerases Tipo II/genética , Regulação da Expressão Gênica de Plantas , Meiose , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética
10.
Mol Biol Rep ; 42(5): 947-62, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25403332

RESUMO

The generation of excess reactive oxygen species (ROS) is one of the most common consequences of abiotic stress on plants. Glutathione reductase (GR, E.C. 1.6.4.2) and allied enzymes of the ascorbate-glutathione cycle play a crucial role to maintain the homeostatic redox balance in the cellular environment. GR plays an essential role in upholding the reduced glutathione pool under stress conditions. In the present study, a full-length GR cDNA and corresponding genomic clone was isolated from Pennisetum glaucum (L.) R. Br. The PgGR cDNA, encodes a 497-amino acid peptide with an estimated molecular mass of ~53.5 kDa. The PgGR peptide exhibits 54-89% sequence homology with GR from other plants and is cytoplasmic in nature. The PgGR enzyme was purified to near homogeneity, the recombinant protein being relatively thermostable and displaying activity in a broad range of temperature, pH and substrate concentrations. The PgGR transcript level was differentially regulated by heat, cold, salinity and methyl viologen-induced oxidative stress. The heterologously expressed PgGR protein in E. coli showed an improved protection against metal- and methyl viologen-induced oxidative stress. Our overall finding underscores the role of PgGR gene that responds to multiple abiotic stresses and provides stress tolerance in the experimental model (E. coli) which can be potentially used for the improvement of crops under abiotic stress conditions.


Assuntos
Glutationa Redutase/genética , Estresse Oxidativo/fisiologia , Pennisetum/enzimologia , Proteínas de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Genes de Plantas , Glutationa Redutase/química , Glutationa Redutase/isolamento & purificação , Glutationa Redutase/metabolismo , Dados de Sequência Molecular , Pennisetum/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Conformação Proteica
11.
Plant Biotechnol J ; 12(9): 1217-30, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25196090

RESUMO

Despite the declarations and collective measures taken to eradicate hunger at World Food Summits, food security remains one of the biggest issues that we are faced with. The current scenario could worsen due to the alarming increase in world population, further compounded by adverse climatic conditions, such as increase in atmospheric temperature, unforeseen droughts and decreasing soil moisture, which will decrease crop yield even further. Furthermore, the projected increase in yields of C3 crops as a result of increasing atmospheric CO2 concentrations is much less than anticipated. Thus, there is an urgent need to increase crop productivity beyond existing yield potentials to address the challenge of food security. One of the domains of plant biology that promises hope in overcoming this problem is study of C3 photosynthesis. In this review, we have examined the potential bottlenecks of C3 photosynthesis and the strategies undertaken to overcome them. The targets considered for possible intervention include RuBisCO, RuBisCO activase, Calvin-Benson-Bassham cycle enzymes, CO2 and carbohydrate transport, and light reactions among many others. In addition, other areas which promise scope for improvement of C3 photosynthesis, such as mining natural genetic variations, mathematical modelling for identifying new targets, installing efficient carbon fixation and carbon concentrating mechanisms have been touched upon. Briefly, this review intends to shed light on the recent advances in enhancing C3 photosynthesis for crop improvement.


Assuntos
Carbono/metabolismo , Produtos Agrícolas/fisiologia , Fotossíntese , Ciclo do Carbono , Ribulose-Bifosfato Carboxilase/metabolismo
12.
Plant Cell Rep ; 33(3): 435-45, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24317405

RESUMO

KEY MESSAGE: PgDHAR was isolated from Pennisetum glaucum. PgDHAR responded to abiotic stress and exhibited enzyme activity at broad ranges of temperature, pH and substrate concentrations suggesting its role in stress tolerance. ABSTRACT: Dehydroascorbate reductase (EC 1.8.5.1) is a crucial enzyme actively involved in the recycling of ascorbate redox pool in the cellular environment. In this study, the full-length cDNA coding for DHAR polypeptide and its corresponding gene was isolated from Pennisetum glaucum (PgDHAR). PgDHAR encodes a polypeptide of 213 amino acids with a predicted molecular mass of 23.4 kDa and shares 80-75 % sequence homology with DHAR from other plants. The heterologously expressed recombinant PgDHAR protein exhibited activity in a wide range of substrate concentrations. The recombinant PgDHAR is thermostable and retains its activity over a broad pH range. Furthermore, transcript level of PgDHAR is quantitatively up-regulated in response to temperature. On the whole, PgDHAR alone or in combination with other genes of ascorbate-glutathione cycle can be used for the development of stress tolerant as well as nutritionally improved food crop with enhanced ascorbic acid content.


Assuntos
Oxirredutases/metabolismo , Pennisetum/enzimologia , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Concentração de Íons de Hidrogênio , Oxirredutases/genética , Pennisetum/genética , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Temperatura
13.
Toxicol Int ; 21(3): 331-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25948978

RESUMO

Potassium permanganate poisoning is not common. Although Symptoms of potassium permanganate ingestion are gastrointestinal and Complications due to ingestion of potassium permanganate include cardiovascular depression, hepatic and renal damage, upper airway obstruction, bleeding tendency and methemoglobinemia. Gastric damage due to potassium permanganate has rarely been reported previously. We are reporting a 34-year old female patient who presented to our Emergency Department after suicidal ingestion of potassium permanganate crystals. After treatment, the patient was discharged home on the 8(th) day after admission. So we conclude that Emergency endoscopy has a significant role in diagnosis and management of potassium permanganate ingestion.

14.
Plant Physiol Biochem ; 194: 302-314, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36442361

RESUMO

In contrast to bacterial, yeast and animal systems, topoisomerases (topo) from plants have not been well studied. In this report, we generated four truncated topoisomerase II (Topo II) cDNA fragments encoding different functional domains of Nicotiana tabacum topo II (NtTopoII). Each of these recombinant polypeptides was expressed alone or in combination in temperature-sensitive topoisomerase II yeast mutants. Recombinant NtTopoII with truncated polypeptides fails to target the yeast nuclei and does not rescue the temperature-sensitive phenotype. In contrast complementation was achieved with the full-length NtTopoII, which localized to the yeast nucleus. These observations suggested the presence of a potent nuclear localization signal (NLS) in the extreme C-terminal 314 amino acid residues of NtTopoII that functioned effectively in the heterologous yeast system. Biochemical characterization of purified recombinant full-length and the partial NtTopoII polypeptides revealed that the ATP-binding and hydrolysis region of NtTopoIIwas located at 413 amino acid N-terminal region and this ATPase domain is functional both when it is expressed as a separate polypeptide or as part of the holoenzyme. The present findings also revealed that all NtTopoII truncated polypeptides were detrimental for in vitro supercoiled DNA relaxation and/or DNA nicking and ligation activity. Further, we discuss the possible disruption of coordinated macromolecular interface movements and the dimer interactions in truncated NtTopoII that are required for functional topoisomerase activity.


Assuntos
DNA Topoisomerases Tipo II , Nicotiana , Animais , DNA Topoisomerases Tipo II/genética , DNA Topoisomerases Tipo II/química , DNA Topoisomerases Tipo II/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Sequência de Aminoácidos , Saccharomyces cerevisiae/metabolismo , Aminoácidos
15.
Ecotoxicol Environ Saf ; 75(1): 16-26, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21899888

RESUMO

Cellular responses to Al-stress in Hordeum vulgare seedling bioassay were evaluated with an objective to identify the possible biomarkers in leaf tissue that would be best suited to biomonitor aluminum (Al) in the environment. Germinating seeds were treated with different concentrations of AlCl(3) at pH 4.5 for 12h. Al-uptake and accumulation in root and leaf, generation of reactive oxygen species (ROS: O(2)(-), H(2)O(2) and ()OH), cell death, activity of antioxidant enzymes: catalase, superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase, lipid peroxidation, protein oxidation, DNase activity and DNA damage were measured in leaf tissue of the seedlings on day 6 after treatment. The above parameters assessed in leaf tissue that followed a dose-response exhibited significant correlation with concentration of Al(3+) in experimental solution as well as in root tissue. The findings underscored the sensitivity as well as potential of Hordeum vulgare seedling bioassay for biomonitoring of Al in the ambient environment.


Assuntos
Alumínio/toxicidade , Hordeum/metabolismo , Folhas de Planta/metabolismo , Poluentes do Solo/toxicidade , Alumínio/metabolismo , Ascorbato Peroxidases/metabolismo , Biomarcadores/metabolismo , Catalase/metabolismo , Morte Celular , Hordeum/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução , Estresse Oxidativo , Peroxidase/metabolismo , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Poluentes do Solo/metabolismo , Superóxido Dismutase/metabolismo
16.
Sci Rep ; 11(1): 21941, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34753955

RESUMO

Enhancing crop productivity and their nutritional quality are the key components and primary focus of crop improvement strategy for fulfilling future food demand and improving human health. Grain filling and endosperm development are the key determinants of grain yield and nutritional quality. GRAIN WIDTH and WEIGHT2 (GW2) gene encodes a RING-type E3 ubiquitin ligase and determines the grain weight in cereal crops. Here we report GW2 knockout (KO) mutants in Indica (var. MTU1010) through CRISPR/Cas9 genome editing. The endosperm of GW2-KO mutant seed displays a thick aleurone layer with enhanced grain protein content. Further the loss of function of OsGW2 results in improved accumulation of essential dietary minerals (Fe, Zn, K, P, Ca) in the endosperm of rice grain. Additionally, the mutants displayed an early growth vigour phenotype with an improved root and shoot architecture. The hull morphology of GW2-KO lines also showed improved, grain filling thereby promoting larger grain architecture. Together, our findings indicate that GW2 may serve as a key regulator of improved grain architecture, grain nutritional quality and an important modulator of plant morphology. The study offers a strategy for the development of improved rice cultivars with enriched nutritional quality and its possible implementation in other cereals as well.


Assuntos
Sistemas CRISPR-Cas , Produtos Agrícolas/genética , Grão Comestível/genética , Mutação , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Técnicas de Silenciamento de Genes , Genes de Plantas
17.
Plant Sci ; 311: 111009, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482912

RESUMO

Weeds, pests, and pathogens are among the pre-harvest constraints in rice farming across rice-growing countries. For weed management, manual weeding and herbicides are widely practiced. Among the herbicides, glyphosate [N-(phosphonomethyl) glycine] is a broad-spectrum systemic chemical extensively used in agriculture. Being a competitive structural analog to phosphoenolpyruvate, it selectively inhibits the conserved 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme required for the biosynthesis of aromatic amino acids and essential metabolites in eukaryotes and prokaryotes. In the present study, we investigated the antifungal and defense elicitor activity of glyphosate against Magnaporthe oryzae on transgenic-rice overexpressing a glyphosate-resistance OsEPSPS gene (T173I + P177S; TIPS OsmEPSPS) for blast disease management. The glyphosate foliar spray on OsmEPSPS transgenic rice lines showed both prophylactic and curative suppression of blast disease comparable to a blasticide, tricyclazole. The glyphosate displayed direct antifungal activity on Magnaporthe oryzae as well as enhanced the levels of antioxidant enzymes and photosynthetic pigments in rice. However, the genes associated with phytohormones-mediated defense (OsPAD4, OsNPR1.3, and OsFMO) and innate immunity pathway (OsCEBiP and OsCERK1) were found repressed upon glyphosate spray. Altogether, the current study is the first report highlighting the overexpression of a crop-specific TIPS mutation in conjugation with glyphosate application showing potential for blast disease management in rice cultivation.


Assuntos
Antifúngicos/farmacologia , Ascomicetos/patogenicidade , Resistência a Herbicidas/genética , Herbicidas/farmacocinética , Oryza/genética , Oryza/microbiologia , Oryza/fisiologia , Doenças das Plantas/prevenção & controle , Ascomicetos/efeitos dos fármacos , Produtos Agrícolas/genética , Produtos Agrícolas/microbiologia , Produtos Agrícolas/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Doenças das Plantas/genética , Plantas Geneticamente Modificadas/genética
18.
PLoS Med ; 7(4): e1000268, 2010 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-20436961

RESUMO

BACKGROUND: Migration from rural areas of India contributes to urbanisation and may increase the risk of obesity and diabetes. We tested the hypotheses that rural-to-urban migrants have a higher prevalence of obesity and diabetes than rural nonmigrants, that migrants would have an intermediate prevalence of obesity and diabetes compared with life-long urban and rural dwellers, and that longer time since migration would be associated with a higher prevalence of obesity and of diabetes. METHODS AND FINDINGS: The place of origin of people working in factories in north, central, and south India was identified. Migrants of rural origin, their rural dwelling sibs, and those of urban origin together with their urban dwelling sibs were assessed by interview, examination, and fasting blood samples. Obesity, diabetes, and other cardiovascular risk factors were compared. A total of 6,510 participants (42% women) were recruited. Among urban, migrant, and rural men the age- and factory-adjusted percentages classified as obese (body mass index [BMI] >25 kg/m(2)) were 41.9% (95% confidence interval [CI] 39.1-44.7), 37.8% (95% CI 35.0-40.6), and 19.0% (95% CI 17.0-21.0), respectively, and as diabetic were 13.5% (95% CI 11.6-15.4), 14.3% (95% CI 12.2-16.4), and 6.2% (95% CI 5.0-7.4), respectively. Findings for women showed similar patterns. Rural men had lower blood pressure, lipids, and fasting blood glucose than urban and migrant men, whereas no differences were seen in women. Among migrant men, but not women, there was weak evidence for a lower prevalence of both diabetes and obesity among more recent (

Assuntos
Diabetes Mellitus/epidemiologia , Obesidade/epidemiologia , Dinâmica Populacional , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos , Adulto Jovem
19.
J Biotechnol ; 310: 68-79, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32014561

RESUMO

Chaperones are a diverse class of molecules known for increasing thermo-stability of proteins, preventing protein aggregation, favoring disaggregation, increasing solubility and in some cases imparting resistance to proteolysis. These functions can be employed for various biotechnological applications including point of care testing, nano-biotechnology, bio-process engineering, purification technologies and formulation development. Here we report that the N-terminal domain of Pyrococcus furiosusl-asparaginase, (NPfA, a protein chaperone lacking α-crystallin domain) can serve as an efficient, industrially relevant, protein additive. We tested the effect of NPfA on substrate proteins, ascorbate peroxidase (APX), IgG peroxidase antibodies (I-HAbs) and KOD DNA polymerase. Each protein not only displayed increased thermal stability but also increased activity in the presence of NPfA. This increase was either comparable or higher than those obtained by common osmolytes; glycine betaine, sorbitol and trehalose. Most dramatic activity enhancement was seen in the case of KOD polymerase (∼ 40 % increase). NPfA exerts its effect through transient binding to the substrate proteins as discerned through isothermal titration calorimetry, dynamic light scattering and size exclusion chromatography. Mechanistic insights obtained through simulations suggested a remodeled architecture and emergence of H-binding network between NPfA and substrate protein with an effective enhancement in the solvent accessibility at the active site pocket of the latter. Thus, the capability of NPfA to engage in specific manner with other proteins is demonstrated to reduce the concentration of substrate proteins/enzymes required per unit operation. The functional expansion obtained through our finding establishes NPfA as a novel class of ATP-independent molecular chaperone with immense future biotechnological applications.


Assuntos
Proteínas Arqueais/química , Asparaginase/química , Chaperonas Moleculares/química , Pyrococcus furiosus/química , Proteínas Arqueais/genética , Asparaginase/genética , Chaperonas Moleculares/genética , Plasmodium falciparum/química , Plasmodium falciparum/genética , Domínios Proteicos , Estabilidade Proteica , Pyrococcus furiosus/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Thermococcus/química , Thermococcus/genética
20.
Lancet Glob Health ; 7(9): e1269-e1279, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31402007

RESUMO

BACKGROUND: Bronchiectasis is a common but neglected chronic lung disease. Most epidemiological data are limited to cohorts from Europe and the USA, with few data from low-income and middle-income countries. We therefore aimed to describe the characteristics, severity of disease, microbiology, and treatment of patients with bronchiectasis in India. METHODS: The Indian bronchiectasis registry is a multicentre, prospective, observational cohort study. Adult patients (≥18 years) with CT-confirmed bronchiectasis were enrolled from 31 centres across India. Patients with bronchiectasis due to cystic fibrosis or traction bronchiectasis associated with another respiratory disorder were excluded. Data were collected at baseline (recruitment) with follow-up visits taking place once per year. Comprehensive clinical data were collected through the European Multicentre Bronchiectasis Audit and Research Collaboration registry platform. Underlying aetiology of bronchiectasis, as well as treatment and risk factors for bronchiectasis were analysed in the Indian bronchiectasis registry. Comparisons of demographics were made with published European and US registries, and quality of care was benchmarked against the 2017 European Respiratory Society guidelines. FINDINGS: From June 1, 2015, to Sept 1, 2017, 2195 patients were enrolled. Marked differences were observed between India, Europe, and the USA. Patients in India were younger (median age 56 years [IQR 41-66] vs the European and US registries; p<0·0001]) and more likely to be men (1249 [56·9%] of 2195). Previous tuberculosis (780 [35·5%] of 2195) was the most frequent underlying cause of bronchiectasis and Pseudomonas aeruginosa was the most common organism in sputum culture (301 [13·7%]) in India. Risk factors for exacerbations included being of the male sex (adjusted incidence rate ratio 1·17, 95% CI 1·03-1·32; p=0·015), P aeruginosa infection (1·29, 1·10-1·50; p=0·001), a history of pulmonary tuberculosis (1·20, 1·07-1·34; p=0·002), modified Medical Research Council Dyspnoea score (1·32, 1·25-1·39; p<0·0001), daily sputum production (1·16, 1·03-1·30; p=0·013), and radiological severity of disease (1·03, 1·01-1·04; p<0·0001). Low adherence to guideline-recommended care was observed; only 388 patients were tested for allergic bronchopulmonary aspergillosis and 82 patients had been tested for immunoglobulins. INTERPRETATION: Patients with bronchiectasis in India have more severe disease and have distinct characteristics from those reported in other countries. This study provides a benchmark to improve quality of care for patients with bronchiectasis in India. FUNDING: EU/European Federation of Pharmaceutical Industries and Associations Innovative Medicines Initiative inhaled Antibiotics in Bronchiectasis and Cystic Fibrosis Consortium, European Respiratory Society, and the British Lung Foundation.


Assuntos
Pesquisa Biomédica/organização & administração , Bronquiectasia/epidemiologia , Bronquiectasia/terapia , Adulto , Idoso , Europa (Continente) , Feminino , Humanos , Índia/epidemiologia , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros
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