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1.
Int J Mol Sci ; 25(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474042

RESUMO

Plants are continuously exposed to various environmental stresses. Because they can not escape stress, they have to develop mechanisms of remembering stress exposures somatically and passing it to the progeny. We studied the Arabidopsis thaliana ecotype Columbia plants exposed to cold stress for 25 continuous generations. Our study revealed that multigenerational exposure to cold stress resulted in the changes in the genome and epigenome (DNA methylation) across generations. Main changes in the progeny were due to the high frequency of genetic mutations rather than epigenetic changes; the difference was primarily in single nucleotide substitutions and deletions. The progeny of cold-stressed plants exhibited the higher rate of missense non-synonymous mutations as compared to the progeny of control plants. At the same time, epigenetic changes were more common in the CHG (C = cytosine, H = cytosine, adenine or thymine, G = guanine) and CHH contexts and favored hypomethylation. There was an increase in the frequency of C to T (thymine) transitions at the CHH positions in the progeny of cold stressed plants; because this type of mutations is often due to the deamination of the methylated cytosines, it can be hypothesized that environment-induced changes in methylation contribute to mutagenesis and may be to microevolution processes and that RNA-dependent DNA methylation plays a crucial role. Our work supports the existence of heritable stress response in plants and demonstrates that genetic changes prevail.


Assuntos
Arabidopsis , Arabidopsis/genética , Epigenômica/métodos , Resposta ao Choque Frio , Timina , Epigênese Genética , Metilação de DNA , Citosina
2.
J Exp Bot ; 70(21): 6245-6259, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31504768

RESUMO

In plants, dioecy characterizes species that carry male and female flowers on separate plants and it occurs in about 6% of angiosperms; however, the molecular mechanisms that underlie dioecy are essentially unknown. The ability for sex-reversal by hormone application raises the hypothesis that the genes required for the expression of both sexes are potentially functional but are regulated by epigenetic means. In this study, proteomic analysis of nuclear proteins isolated from flower buds of females, males, and feminized males of the dioecious plant Mercurialis annua revealed differential expression of nuclear proteins that are implicated in chromatin structure and function, including floral homeotic proteins. Focusing on floral genes, we found that class B genes were mainly expressed in male flowers, while class D genes, as well as SUPERMAN-like genes, were mainly expressed in female flowers. Cytokinin-induced feminization of male plants was associated with down-regulation of male-specific genes concomitantly with up-regulation of female-specific genes. No correlation was found between the expression of class B and D genes and the changes in DNA methylation or chromatin conformation of these genes. Thus, we could not confirm DNA methylation or chromatin conformation of floral genes to be the major determinant regulating sexual dimorphisms. Instead, determination of sex in M. annua might be controlled upstream of floral genes by one or more sex-specific factors that affect hormonal homeostasis. A comprehensive model is proposed for sex-determination in M. annua.


Assuntos
Epigênese Genética , Euphorbiaceae/genética , Genes Homeobox , Genes de Plantas , Caracteres Sexuais , Núcleo Celular/metabolismo , Cromatina/metabolismo , Flores/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Domínio MADS/genética , Proteoma/metabolismo , Transcrição Gênica
3.
Med J Armed Forces India ; 75(3): 325-329, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31388238

RESUMO

BACKGROUND: Weightlifting is a power and dynamic strength game. Performance of weightlifters during competition depends on absolute and relative power output achieved by them. To enhance power and strength in weightlifters, training programmes have frequent high-intensity exercise sessions. On an informal interaction with the sportspersons, they often complain of problems after intense training. There was a felt need to analyse the problems they perceive after intense training. METHOD: A feedback form was developed after brainstorming with coaches and sports medicine physicians of a sports institute. Thirty-six male weightlifters aged 19.78 ± 4.71 yrs (mean ± standard deviation) of an institute participated after obtaining informed consent. The feedback form was collected and analysed. RESULT: After an intense exercise, participants reported complaints such as increased fatigue (n = 27), sleep problems (n = 26), restlessness (n = 18) and decreased appetite (n = 12). Of the sleep problems, 69.4% (n = 25 out of 36) noticed worsening of sleep, 50% (n = 18) noticed sleep was light after intense training, 58.3% (n = 21) felt difficulty in falling asleep, 47.2% (n = 7) complained of frequent waking up during sleep at night and 77.8% (n = 28) felt sleepy after waking up. CONCLUSION: Intense training encounters certain problems such as fatigue, sleep disturbances, restlessness and decreased appetite.

4.
Biochim Biophys Acta ; 1859(10): 1289-98, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27475038

RESUMO

Dedifferentiation, that is, the acquisition of stem cell-like state, commonly induced by stress (e.g., protoplasting), is characterized by open chromatin conformation, a chromatin state that could lead to activation of transposable elements (TEs). Here, we studied the activation of the Arabidopsis class II TE Tag1, in which two copies, situated close to each other (near genes) on chromosome 1 are found in Landsberg erecta (Ler) but not in Columbia (Col). We first transformed protoplasts with a construct in which a truncated Tag1 (ΔTag1 non-autonomous) blocks the expression of a reporter gene AtMBD5-GFP and found a relatively high ectopic excision of ΔTag1 accompanied by expression of AtMBD5-GFP in protoplasts derived from Ler compared to Col; further increase was observed in ddm1 (decrease in DNA methylation1) protoplasts (Ler background). Ectopic excision was associated with transcription of the endogenous Tag1 and changes in histone H3 methylation at the promoter region. Focusing on the endogenous Tag1 elements we found low level of excision in Ler protoplasts, which was slightly and strongly enhanced in ddm1 and cmt3 (chromomethylase3) protoplasts, respectively, concomitantly with reduction in Tag1 gene body (GB) CHG methylation and increased Tag1 transcription; strong activation of Tag1 was also observed in cmt3 leaves. Notably, in cmt3, but not in ddm1, Tag1 elements were excised out from their original sites and transposed elsewhere in the genome. Our results suggest that dedifferentiation is associated with Tag1 activation and that CMT3 rather than DDM1 plays a central role in restraining Tag1 activation via inducing GB CHG methylation.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Elementos de DNA Transponíveis , Proteínas de Ligação a DNA/genética , DNA-Citosina Metilases/genética , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição/genética , Transposases/genética , Arabidopsis/citologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Desdiferenciação Celular , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , DNA-Citosina Metilases/metabolismo , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Histonas/genética , Histonas/metabolismo , Células Vegetais/metabolismo , Folhas de Planta/citologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Protoplastos/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Transformação Genética , Transposases/metabolismo
5.
Parasitology ; 142(5): 728-44, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25498563

RESUMO

In earlier studies, proteomic characterization of splenic amastigote fractions from clinical isolates of Leishmania donovani, exhibiting significant cellular responses in cured Leishmania subjects, led to the identification of cytosolic tryparedoxin peroxidase (LdcTryP) and chaperonin-TCP20 (LdTCP20) as Th1-stimulatory proteins. Both the proteins, particularly LdTCP20 for the first time, were successfully cloned, overexpressed, purified and were found to be localized in the cytosol of purified splenic amastigotes. When evaluated against lymphocytes of cured Leishmania-infected hamsters, the purified recombinant proteins (rLdcTryP and rLdTCP20) induced their proliferations as well as nitric oxide production. Similarly, these proteins also generated Th1-type cytokines (IFN-γ/IL-12) from stimulated PBMCs of cured/endemic Leishmania patients. Further, vaccination with rLdcTryP elicited noticeable delayed-type hypersensitivity response and offered considerably good prophylactic efficacy (~78% inhibition) against L. donovani challenge in hamsters, which was well supported by the increased mRNA expression of Th1 and Th2 cytokines. However, animals vaccinated with rLdTCP20 exhibited comparatively lesser prophylactic efficacy (~55%) with inferior immunological response. The results indicate the potentiality of rLdcTryP protein, between the two, as a suitable anti-leishmanial vaccine. Since, rLdTCP20 is also an important target, for optimization, further attempts towards determination of immunodominant regions for designing fusion peptides may be taken up.


Assuntos
Proteínas de Choque Térmico/imunologia , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Peroxidases/imunologia , Proteínas de Protozoários/imunologia , Animais , Chaperoninas/imunologia , Cricetinae , Feminino , Humanos , Immunoblotting , Leishmania donovani/enzimologia , Leishmaniose Visceral/parasitologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Linfonodos/citologia , Masculino , Mesocricetus , Óxido Nítrico/metabolismo , Proteínas Recombinantes/imunologia , Baço/parasitologia
6.
Trop Med Int Health ; 18(6): 743-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23682856

RESUMO

OBJECTIVE: Until 2010, no Japanese encephalitis (JE) had been reported from Delhi. Upon report of four confirmed cases of JE in September 2011, detailed investigations were carried out to determine whether the cases were imported or indigenous. METHODS: Entomological surveys were carried out and all mosquito pools were tested for the detection of JE virus by ELISA method using specific monoclonal antibody. Human blood samples from contacts of the patients were tested by IgM-captured ELISA method. Pig's blood samples were also tested for the detection of JE virus. RESULTS: Culex tritaeniorhynchus, Culex vishnui and Culex pseudovishnui mosquitoes were found. In contrast to rural areas, their breeding habitats were different in the city. 19 pools were tested. JE virus was detected in two pools of Cx. tritaeniorhynchus females reared from field-collected larvae, indicating vertical transmission. One pool of Cx. vishnui was also positive. This is the first report for the detection of JE virus in mosquitoes from Delhi. JE IgM antibodies in five contacts/residents indicate recent infection. JE virus was also detected in pigs. CONCLUSION: Present analysis shows that of four reported JE cases, three were confirmed indigenous, indicating that the virus is multiplying in the city. Mapping of infected JE vector mosquitoes in the cities is required for preventive measures to contain further spread of the disease.


Assuntos
Culex/virologia , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Encefalite Japonesa/transmissão , Insetos Vetores/virologia , Adolescente , Adulto , Animais , Anticorpos Antivirais/sangue , Criança , Culex/crescimento & desenvolvimento , Vírus da Encefalite Japonesa (Espécie)/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina M/sangue , Índia , Insetos Vetores/crescimento & desenvolvimento , Masculino , População Urbana
7.
Appl Microbiol Biotechnol ; 97(5): 1973-85, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22639141

RESUMO

ω-3 fatty acid desaturase is a key enzyme for the biosynthesis of ω-3 polyunsaturated fatty acids via the oxidative desaturase/elongase pathways. Here we report the identification of three ω-3 desaturases from oomycetes, Pythium aphanidermatum, Phytophthora sojae, and Phytophthora ramorum. These new ω-3 desaturases share 55 % identity at the amino acid level with the known Δ-17 desaturase of Saprolegnia diclina, and about 31 % identity with the bifunctional Δ-12/Δ-15 desaturase of Fusarium monoliforme. The three enzymes were expressed in either wild-type or codon optimized form in an engineered arachidonic acid producing strain of Yarrowia lipolytica to study their activity and substrate specificity. All three were able to convert the ω-6 arachidonic acid to the ω-3 eicosapentanoic acid, with a substrate conversion efficiency of 54-65 %. These enzymes have a broad ω-6 fatty acid substrate spectrum, including both C18 and C20 ω-6 fatty acids although they prefer the C20 substrates, and have strong Δ-17 desaturase activity but weaker Δ-15 desaturase activity. Thus, they belong to the Δ-17 desaturase class. Unlike the previously identified bifunctional Δ-12/Δ-15 desaturase from F. monoliforme, they lack Δ-12 desaturase activity. The newly identified Δ-17 desaturases could use fatty acids in both acyl-CoA and phospholipid fraction as substrates. The identification of these Δ-17 desaturases provides a set of powerful new tools for genetic engineering of microbes and plants to produce ω-3 fatty acids, such as eicosapentanoic acid and docosahexanoic acid, at high levels.


Assuntos
Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Phytophthora/enzimologia , Pythium/enzimologia , Sequência de Aminoácidos , Ácido Araquidônico/metabolismo , Biotransformação , Clonagem Molecular , Ácido Eicosapentaenoico/metabolismo , Expressão Gênica , Modelos Moleculares , Dados de Sequência Molecular , Phytophthora/genética , Pythium/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saprolegnia/enzimologia , Saprolegnia/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Yarrowia/genética
8.
J Microbiol Immunol Infect ; 56(1): 163-171, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35835687

RESUMO

BACKGROUND: Available therapeutics for visceral leishmaniasis (VL), a deadly parasitic infection, are usually associated with inadequate efficacy and adverse aftereffects. Further, the primary site of Leishmania parasite are host macrophages resulting in compromised immunity; ensuing marked T-cell immunosuppression. Such settings emphasize the exploration of chemo-immunotherapeutic strategies for improvising the infected person's immune status with better resolution of infection. METHODS: Present work employs the immunization of Leishmania-infected hamsters with Leishmania-derived recombinant aldolase (rLdAld) and enolase (rLdEno) proteins in consort with the sub-optimal dose of Ambisome (2.5 mg/kg). After the completion of immunization, hamsters were sacrificed on day 60 and 90 post infection and different organ samples were collected to perform immunological assay for evaluating the therapeutic efficacy and modulation in protective cellular immune responses. RESULTS: Combining these proteins, particularly rLdAld with Ambisome (2.5 mg/kg), has significantly reduced the parasitic load (∼80%) with remarkable enhancement in DTH and lymphoproliferative responses compared to the infected control and only Ambisome treated groups. Moreover, cytokine levels at RNA and protein levels were noticed to be inclined towards Th-1 phenotype through up-regulation of IFN-γ and TNF-α with significant down-regulation in IL-10 and TGF-ß expression, an indication towards the generation of protective immunity against experimental VL. CONCLUSION: Our experimental findings demonstrated that the chemo-immunotherapeutic approach could be an effective way of controlling human VL infection at minimal dosages of antileishmanial with reduced side-effects and propensity of drug resistance emergence.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Cricetinae , Animais , Humanos , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Frutose-Bifosfato Aldolase/genética , Frutose-Bifosfato Aldolase/farmacologia , Frutose-Bifosfato Aldolase/uso terapêutico , Imunização , Citocinas
9.
Curr Probl Cardiol ; 48(9): 101749, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37087079

RESUMO

Nationwide data of the COVID-19 pandemic's impact on heart failure (HF) hospitalizations is lacking. We conducted this study to elucidate the impact of the COVID-19 pandemic on HF hospitalizations. Additionally, we assessed the differences in hospitalization characteristics during the pandemic and the impact that a concurrent diagnosis of COVID-19 has on various outcomes and predictors of inpatient mortality among patients admitted for HF. The National Inpatient Sample (NIS) database was queried for all hospitalizations with a primary diagnosis of HF between 2017 and 2020. Monthly HF hospitalizations were trended longitudinally over this period. Beginning April 1, 2020, concurrent COVID-19 infections were identified. Subsequently, we stratified HF hospitalizations between April 2020 and December 2020 (HF-2020) based on if concomitant COVID-19 was diagnosed, forming the HF-COVID+ve and HF-COVID-ve groups respectively. HF-2020 was also compared with prepandemic HF hospitalizations between April 2019 and December 2019 (HF-2019). Baseline characteristics were compared, and adjusted outcomes were obtained. During the initial COVID-19 surge in April 2020, HF admissions were reduced by 47% compared to January 2020. Following this decline, HF hospitalizations increased but did not reach prepandemic levels. HF-2020 admissions had an increased complication burden compared to HF-2019, including acute myocardial infarction (8.9% vs 6.6%, P < 0.005) and pulmonary embolism (4.1% vs 3.4%, P < 0.005) indicating a sicker cohort of patients. HF-COVID+ve hospitalizations had 2.9 times higher odds of inpatient mortality compared to HF-COVID-ve and an increased adjusted length of stay by 2.16 days (P < 0.005). A pandemic of the same magnitude as COVID-19 can overwhelm even the most advanced health systems. Early resource mobilization and preparedness is essential to provide care to a sick cohort of patients like acute HF, who are directly and indirectly effected by the consequences of the pandemic which has worsened hospitalization outcomes.


Assuntos
COVID-19 , Insuficiência Cardíaca , Infarto do Miocárdio , Humanos , Estados Unidos/epidemiologia , Pandemias , COVID-19/epidemiologia , COVID-19/complicações , Hospitalização , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/diagnóstico
10.
BMC Plant Biol ; 12: 188, 2012 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-23057782

RESUMO

BACKGROUND: Soil salinity adversely affects plant growth and development and disturbs intracellular ion homeostasis resulting cellular toxicity. The Salt Overly Sensitive 1 (SOS1) gene encodes a plasma membrane Na(+)/H(+) antiporter that plays an important role in imparting salt stress tolerance to plants. Here, we report the cloning and characterisation of the SbSOS1 gene from Salicornia brachiata, an extreme halophyte. RESULTS: The SbSOS1 gene is 3774 bp long and encodes a protein of 1159 amino acids. SbSOS1 exhibited a greater level of constitutive expression in roots than in shoots and was further increased by salt stress. Overexpressing the S. brachiata SbSOS1 gene in tobacco conferred high salt tolerance, promoted seed germination and increased root length, shoot length, leaf area, fresh weight, dry weight, relative water content (RWC), chlorophyll, K(+)/Na(+) ratio, membrane stability index, soluble sugar, proline and amino acid content relative to wild type (WT) plants. Transgenic plants exhibited reductions in electrolyte leakage, reactive oxygen species (ROS) and MDA content in response to salt stress, which probably occurred because of reduced cytosolic Na(+) content and oxidative damage. At higher salt stress, transgenic tobacco plants exhibited reduced Na(+) content in root and leaf and higher concentrations in stem and xylem sap relative to WT, which suggests a role of SbSOS1 in Na(+) loading to xylem from root and leaf tissues. Transgenic lines also showed increased K(+) and Ca(2+) content in root tissue compared to WT, which reflect that SbSOS1 indirectly affects the other transporters activity. CONCLUSIONS: Overexpression of SbSOS1 in tobacco conferred a high degree of salt tolerance, enhanced plant growth and altered physiological and biochemical parameters in response to salt stress. In addition to Na(+) efflux outside the plasma membrane, SbSOS1 also helps to maintain variable Na(+) content in different organs and also affect the other transporters activity indirectly. These results broaden the role of SbSOS1 in planta and suggest that this gene could be used to develop salt-tolerant transgenic crops.


Assuntos
Chenopodiaceae/genética , Nicotiana/fisiologia , Plantas Tolerantes a Sal/genética , Cloreto de Sódio/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Xilema/metabolismo , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Trocadores de Sódio-Hidrogênio/genética , Nicotiana/genética , Transformação Genética
11.
Yeast ; 29(1): 25-38, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22189651

RESUMO

Diacylglycerol (DAG) acyltransferase catalyses the final and committed step of triacylglycerol biosynthesis. Eukaryotes commonly contain up to three distinct classes of DAG acyltransferases: acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1), acyl-CoA:diacylglycerol acyltransferase 2 (DGAT2), and phospholipid:diacylglycerol acyltransferase (PDAT). The non-conventional oleaginous yeast, Yarrowia lipolytica, contains at least one homologue of each class and serves as a good model to understand the role of different DAG acyltransferases in the biosynthesis of oil, a critical cellular component that serves as a storage molecule as well as a buffer for free fatty acids. We used gene disruptions in Y. lipolytica and in vitro enzyme assays to confirm the identity of genes encoding all three DAG acyltransferases and demonstrate that together they account for almost all oil biosynthesis and that all three contribute significantly to its oil biosynthesis. In Y. lipolytica ATCC 20362 strain, the total lipid% dry cell weight (DCW) as a percentage of the wild-type strain in pdat, dgat1, dgat2, dgat1/dgat2 double mutant and dgat1/dgat2/pdat triple mutant was 70%, 57%, 36%, 18% and 13%, respectively.This is the first example of DGAT1 contributing significantly to oil biosynthesis in a microorganism. The triple mutant shows significant growth defect in both increased lag phase and slower growth rate, suggesting that oil biosynthesis contributes to normal growth in this strain.


Assuntos
Diacilglicerol O-Aciltransferase/metabolismo , Proteínas Fúngicas/metabolismo , Óleos/metabolismo , Yarrowia/enzimologia , Diacilglicerol O-Aciltransferase/genética , Proteínas Fúngicas/genética , Mutação , Yarrowia/genética , Yarrowia/crescimento & desenvolvimento , Yarrowia/metabolismo
12.
Mol Biol Rep ; 39(2): 1943-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21655957

RESUMO

Salicornia brachiata is one of the extreme salt tolerant plants and grows luxuriantly in coastal areas. Previously we have reported isolation and characterization of ESTs from S. brachiata with large number of unknown gene sequences. Reverse Northern analysis showed upregulation and downregulation of few unknown genes in response to salinity. Some of these unknown genes were made full length and their functional analysis is being tested. In this study, we have selected a novel unknown salt inducible gene SbSI-1 (Salicornia brachiata salt inducible-1) for the functional validation. The SbSI-1 (Gen-Bank accession number JF 965339) was made full length and characterized in detail for its functional validation under desiccation and salinity. The SbSI-1 gene is 917 bp long, and contained 437 bp 3' UTR, and 480 bp ORF region encoding 159 amino acids protein with estimated molecular mass of 18.39 kDa and pI 8.58. The real time PCR analysis revealed high transcript expression in salt, desiccation, cold and heat stresses. However, the maximum expression was obtained by desiccation. The ORF region of SbSI-1 was cloned in pET28a vector and transformed in BL21 (DE3) E. coli cells. The SbSI-1 recombinant E. coli cells showed tolerance to desiccation and salinity stress compared to only vector in the presence of stress.


Assuntos
Adaptação Fisiológica/genética , Chenopodiaceae/genética , Desidratação , Genes de Plantas/genética , Salinidade , Estresse Fisiológico/genética , Northern Blotting , Clonagem Molecular , Primers do DNA/genética , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Vetores Genéticos , Fases de Leitura Aberta/genética , Reação em Cadeia da Polimerase em Tempo Real , Transformação Bacteriana
13.
Front Plant Sci ; 13: 728167, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35419019

RESUMO

Plants are sedentary organisms that constantly sense changes in their environment and react to various environmental cues. On a short-time scale, plants respond through alterations in their physiology, and on a long-time scale, plants alter their development and pass on the memory of stress to the progeny. The latter is controlled genetically and epigenetically and allows the progeny to be primed for future stress encounters, thus increasing the likelihood of survival. The current study intended to explore the effects of multigenerational heat stress in Arabidopsis thaliana. Twenty-five generations of Arabidopsis thaliana were propagated in the presence of heat stress. The multigenerational stressed lineage F25H exhibited a higher tolerance to heat stress and elevated frequency of homologous recombination, as compared to the parallel control progeny F25C. A comparison of genomic sequences revealed that the F25H lineage had a three-fold higher number of mutations [single nucleotide polymorphisms (SNPs) and insertions and deletions (INDELs)] as compared control lineages, suggesting that heat stress induced genetic variations in the heat-stressed progeny. The F25H stressed progeny showed a 7-fold higher number of non-synonymous mutations than the F25C line. Methylome analysis revealed that the F25H stressed progeny showed a lower global methylation level in the CHH context than the control progeny. The F25H and F25C lineages were different from the parental control lineage F2C by 66,491 and 80,464 differentially methylated positions (DMPs), respectively. F25H stressed progeny displayed higher frequency of methylation changes in the gene body and lower in the body of transposable elements (TEs). Gene Ontology analysis revealed that CG-DMRs were enriched in processes such as response to abiotic and biotic stimulus, cell organizations and biogenesis, and DNA or RNA metabolism. Hierarchical clustering of these epimutations separated the heat stressed and control parental progenies into distinct groups which revealed the non-random nature of epimutations. We observed an overall higher number of epigenetic variations than genetic variations in all comparison groups, indicating that epigenetic variations are more prevalent than genetic variations. The largest difference in epigenetic and genetic variations was observed between control plants comparison (F25C vs. F2C), which clearly indicated that the spontaneous nature of epigenetic variations and heat-inducible nature of genetic variations. Overall, our study showed that progenies derived from multigenerational heat stress displayed a notable adaption in context of phenotypic, genotypic and epigenotypic resilience.

14.
Chemosphere ; 307(Pt 3): 135958, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35952796

RESUMO

Paclobutrazol (PBZ) role in drought management of maize is least understood. In maize, root traits are linked with surface water management. Over three years, early and terminal deficit irrigation (EDI and TDI) with or without PBZ were imposed on DKC-9144 and PG-2475 maize varieties. Several allometric parameters viz. stem height, stem diameter, leaf area and root traits along with physiological processes were measured. Implication of these parameters in the management of soil surface irrigation in terms of water use efficiency (WUE) was demonstrated in maize. Increased number of lateral roots and root number density in DKC-9144 provided more surface area for water absorption for better management of EDI. Root growth rates showed a similar pattern with root length, root surface areas, and root numbers in EDI. Elevated expressions of ZmRTCL, ZmRTCS and ZmARF34 in EDI and EDI plus PBZ were associated with seminal roots and root laterals initiation. Under TDI alone or in combination with PBZ, root lengths (BRL, CRL, SRL) and root surface areas varied in DKC-9144 and PG-2475 over control. Furthermore, correlation analysis showed that decrease in WUE under TDI was significantly associated with a reduction in stem thickness and leaf surface area. For WUE_N in TDI and PBZ plus TDI, structural equation modelling proposed, brace root surface area (BRSA_N) as a positive contributor, while a negative contributor was seminal root surface area (SRSA_N). Present study explained the importance of specific root traits and their association with other allometric parameters for improving WUE in DKC-9144 variety of maize and the crop in general.


Assuntos
Água , Zea mays , Raízes de Plantas/metabolismo , Solo , Triazóis/metabolismo , Água/metabolismo , Zea mays/metabolismo
15.
Cureus ; 14(9): e29317, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36161997

RESUMO

The gut microbiota (GM) has been recognized as an important factor in the development of metabolic diseases such as obesity; it has been reported that the composition of the GM differs in obese and lean subjects, suggesting that microbiota dysbiosis can contribute to changes in body weight. Dysbiosis occurs due to an imbalance in the composition of gut bacteria, changes in the metabolic process, or changes in the distribution of microbiota within the gut. Dysbiosis can change the functioning of the intestinal barrier and the gut-associated lymphoid tissues (GALT). Microbial manipulation may help with preventing or treating weight gain and associated comorbidities. Approaches to this may range from dietary manipulation, which is suitable to treat the individual's microflora, to probiotics, prebiotics, synbiotics, and fecal microbiota transplant (FMT).

16.
PLoS One ; 17(3): e0264895, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35263360

RESUMO

BACKGROUND: Smoke-free legislation banning tobacco smoking in public places was implemented across Nepal in 2014 with the ambition to reduce the impact of second-hand smoking. As part of a comprehensive policy package on tobacco control, the implementation of the legislation has seen a marked reduction in tobacco consumption. Yet there remains uncertainty about the level of compliance with smoke-free public places. OBJECTIVES: This study assesses the compliance with smoke-free laws in public places and the factors associated with active smoking in public places in Biratnagar Metropolitan City, Nepal. METHODS: A cross-sectional study was conducted in the Biratnagar metropolitan city in Province 1 of Nepal from July to December 2019. A total of 725 public places within the metropolitan city were surveyed using a structured survey tool. Active smoking was the primary outcome of the study which was defined as smoking by any person during the data collection time at the designated public place. RESULTS: The overall compliance with smoke-free legislation was 56.4%. The highest compliance (75.0%) was observed in Government office buildings. The lowest compliance was observed in eateries, entertainment, and shopping venues (26.3%). There was a statistically significant association between active smoking and the presence of 'no smoking' notices appended at the entrance and the odds of active smoking in eateries, entertainment, hospitality, shopping venues, transportations and transits was higher compared to education and health care institutions. None of the 'no smoking' notices displayed fully adhered to the contents as prescribed by the law. CONCLUSION: As more than half of the public places complied with the requirements of the legislation, there was satisfactory overall compliance with the smoke-free public places law in this study. The public venues (eateries, shopping venues and transportations) that are more frequently visited and have a high turnover of the public have lower compliance with the legislation. The content of the message in the 'no smoking' notices needs close attention to adhere to the legal requirements.


Assuntos
Política Antifumo , Produtos do Tabaco , Poluição por Fumaça de Tabaco , Estudos Transversais , Humanos , Nepal , Restaurantes , Inquéritos e Questionários , Poluição por Fumaça de Tabaco/prevenção & controle
17.
Mol Biol Rep ; 38(3): 1965-73, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20853145

RESUMO

Salinity causes multifarious adverse effects to plants. Plants response to salt stress involves numerous processes that function in coordination to alleviate both cellular hyperosmolarity and ion disequilibrium. A Na(+)/H(+) antiporter NHX1 gene has been isolated from a halophytic plant Salicornia brachiata in this study. Predicted amino acid sequence similarity, protein topology and the presence of functional domains conserved in SbNHX1 classify it as a plant vacuolar NHX gene. The SbNHX1 cDNA has an open reading frame of 1,683 bp, encoding a polypeptide of 560 amino acid residues with an estimated molecular mass 62.44 kDa. The SbNHX1 shows high amino acid similarity with other halophytic NHX gene and belongs to Class-I type NHXs. TMpred suggests that SbNHX1 contains 11 strong transmembrane (TM). Real time PCR analysis revealed that SbNHX1 transcript expresses maximum at 0.5 M. Transcript increases gradually by increasing the treatment duration at 0.5 M NaCl, however, maximum expression was observed at 48 h. The overexpression of SbNHX1 gene in tobacco plant showed NaCl tolerance. This study shows that SbNHX1 is a potential gene for salt tolerance, and can be used in future for developing salt tolerant crops.


Assuntos
Chenopodiaceae/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Proteínas de Plantas/genética , Trocadores de Sódio-Hidrogênio/genética , Estresse Fisiológico/genética , Chenopodiaceae/efeitos dos fármacos , Clonagem Molecular , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Filogenia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Cloreto de Sódio/farmacologia , Trocadores de Sódio-Hidrogênio/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Nicotiana/efeitos dos fármacos , Nicotiana/genética , Transformação Genética/efeitos dos fármacos
18.
Plants (Basel) ; 10(12)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34961245

RESUMO

Herbal and plant extracts exhibit various types of properties and activities that have been applied in the medicinal field to treat diseases and achieve better health [...].

19.
Bio Protoc ; 11(1): e3875, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33732764

RESUMO

Cannabis seed germination is an important process for growers and researchers alike. Many biotechnological applications require a reliable sterile method for seed germination. This protocol outlines a seed germination procedure for Cannabis sativa using a hydrogen peroxide (H2O2) solution as liquid germination media. In this protocol, all three steps including seed sterilization, germination, and seedlings development were carried out in an H2O2 solution of different concentrations; 1% H2O2 solution showed the fastest and the most efficient germination. This protocol also exhibited high germination efficiency for very old cannabis seeds with lower viability. Overall, this protocol demonstrates superior germination compared to water control and reduces the risk of contamination, making it suitable for tissue culture and other sensitive applications.

20.
Biomed Res Int ; 2021: 8845826, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095312

RESUMO

Immunotherapy, a treatment based on host immune system activation, has been shown to provide a substitute for marginally effective conventional chemotherapy in controlling visceral leishmaniasis (VL), the deadliest form of leishmaniasis. As the majority of endemic inhabitants exhibit either subclinical or asymptomatic infection which often develops into the active disease state, therapeutic intervention seems to be an important avenue for combating infections by stimulating the natural defense system of infected individuals. With this perspective, the present study focuses on two immunodominant Leishmania (L.) donovani antigens (triosephosphate isomerase and enolase) previously proved to be potent prophylactic VL vaccine candidates, for generating a recombinant chimeric antigen. This is based on the premise that in a heterogeneous population, a multivalent antigen vaccine would be required for an effective response against leishmaniasis (a complex parasitic disease). The resulting molecule rLdT-E chimeric protein was evaluated for its immunogenicity and immunotherapeutic efficacy. A Th1 stimulating adjuvant BCG was employed with the protein which showed a remarkable 70% inhibition of splenic parasitic multiplication positively correlated with boosted Th1 dominant immune response against lethal L. donovani challenge in hamsters as evidenced by high IFN-γ and TNF-α and low IL-10. In addition, immunological analysis of antibody subclass presented IgG2-based humoral response besides considerable delayed-type hypersensitivity and lymphocyte proliferative responses in rLdT-E/BCG-treated animals. Our observations indicate the potential of the chimera towards its candidature for an effective vaccine against Leishmania donovani infection.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Células Th1 , Animais , Cricetinae , Feminino , Imunidade Adaptativa/imunologia , Antígenos de Protozoários/imunologia , Citocinas/metabolismo , Fatores Imunológicos/metabolismo , Imunoterapia/métodos , Leishmania donovani/genética , Leishmania donovani/imunologia , Leishmania donovani/patogenicidade , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/metabolismo , Leishmaniose Visceral/terapia , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária/imunologia , Linfócitos/metabolismo , Fosfopiruvato Hidratase/imunologia , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes/metabolismo , Células Th1/imunologia , Triose-Fosfato Isomerase/imunologia , Vacinas/farmacologia
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