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1.
Artigo em Inglês | MEDLINE | ID: mdl-37833591

RESUMO

In today's corporate world, a company's long-term viability and prosperity depend on its corporate governance practices. The present study investigates the interplay between financial misrepresentation, earnings management, and corporate governance within the context of Pakistan. To estimate the financial data of enterprises obtained from non-financial organizations listed on the Pakistan Stock Exchange a panel regression analysis was conducted. The analysis covered the time from 2009 to 2020 and employed quantitative data. The findings of the study show that the different aspects of corporate governance mechanisms have varying levels of influence. Specifically, remuneration paid to directors had a significant impact on financial misstatement, while the size of the board strongly impacts the earning management. The financial misstatement was also found affected by the earning management. The M score (statistical model used to predict the probability of financial misstatement) positively influenced when board diligence was incorporated in the mediation of earning management. It is important to note that this study only considers the internal governance mechanisms of firms, suggesting that future research could benefit from the inclusion of external governance mechanisms for a more holistic model. This study is aligned with the ESG's governance aspects and SDG-17, providing valuable insights for specialists, financial backers, policymakers, and experts. The results of this study catalyze further research in this area and can aid in achieving SDG 17 by raising awareness of the significance of good governance practices, ethical reporting that leads to sustainable firm performance, and ensuring long-term economic growth and development.

2.
Heliyon ; 9(8): e19014, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37654454

RESUMO

Many state-owned enterprises have mergers and acquisitions (M&A) with private enterprises, which has caused private enterprises to worry about their living space being squeezed. Based on 572 data records about equity transfers of Chinese listed companies extracted from CSMAR4.0 from 2013 to 2020, this paper categorized ownership structures into three categories: privatization of state-owned enterprises (Category 1), state-owned enterprises merging private enterprises (Category 2), and state-owned enterprises merging state-owned enterprises (Category 3). The categorical regression of ex-ante equity transfer motivation revealed that the motives for Category 1 conformed to the phenomenon of the "pretty girl gets married first" and "embezzlement view." Category In contrast, the motives for Category 2 conformed to the "fiscal revenue view." The categorical regression of ex-post equity transfer motivation showed that all three types significantly improved various efficiencies and represented an optimal allocation of resources. Moreover, it was revealed that the transfer of equity to state-owned enterprises by inefficient private firms in Category 2 also significantly improved enterprise efficiency. Thus, it can be considered as a rational behavior of market selection and never squeezed the space crowding. Further analysis showed that the efficiency improvement is due to the symbiotic development relationship rather than the antagonistic relationship between heterogeneous shareholders. Therefore, it is suggested to initiate market-oriented reform by actively developing ownership mixed-ownership economy and adhering to the "two unwavering" basic economic system.

3.
Access Microbiol ; 5(7)2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601434

RESUMO

Here we report draft-quality genome sequences for pathotype strains of eight plant-pathogenic bacterial pathovars: Xanthomonas campestris pv. asclepiadis, X. campestris pv. cannae, X. campestris pv. esculenti, X. campestris pv. nigromaculans, X. campestris pv. parthenii, X. campestris pv. phormiicola, X. campestris pv. zinniae and X. dyei pv. eucalypti (= X. campestris pv. eucalypti). We also sequenced the type strain of species X. melonis and the unclassified Xanthomonas strain NCPPB 1067. These data will be useful for phylogenomic and taxonomic studies, filling some important gaps in sequence coverage of Xanthomonas phylogenetic diversity. We include representatives of previously under-sequenced pathovars and species-level clades. Furthermore, these genome sequences may be useful in elucidating the molecular basis for important phenotypes, such as biosynthesis of coronatine-related toxins and degradation of fungal toxin cercosporin.

4.
Heliyon ; 9(8): e18574, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37576208

RESUMO

This study attempts to investigate the mediating role of institutional quality on the relationship between public debt and economic growth in Pakistan spanning 1996-2020. Time series data on all six World Bank World Governance indicators of institutional quality is used in the empirical analysis. Findings of the autoregressive distributed lag (ARDL) bounds testing technique and error correction method (ECM) confirmed the existence of cointegration among variables of interest. The short-run results indicate that public debt has a favorable association with economic growth, while the relationship is found to be detrimental in the long run. Furthermore, the combined effect of public debt and institutional quality indicators revealed the significant positive association with economic growth, suggesting that better institutional quality can contribute to mitigate the negative impact of public debt on economic growth in Pakistan.

5.
Microbiome ; 11(1): 146, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37394496

RESUMO

BACKGROUND: Despite the knowledge that the soil-plant-microbiome nexus is shaped by interactions amongst its members, very little is known about how individual symbioses regulate this shaping. Even less is known about how the agriculturally important symbiosis of nitrogen-fixing rhizobia with legumes is impacted according to soil type, yet this knowledge is crucial if we are to harness or improve it. We asked how the plant, soil and microbiome are modulated by symbiosis between the model legume Medicago truncatula and different strains of Sinorhizobium meliloti or Sinorhizobium medicae whose nitrogen-fixing efficiency varies, in three distinct soil types that differ in nutrient fertility, to examine the role of the soil environment upon the plant-microbe interaction during nodulation. RESULTS: The outcome of symbiosis results in installment of a potentially beneficial microbiome that leads to increased nutrient uptake that is not simply proportional to soil nutrient abundance. A number of soil edaphic factors including Zn and Mo, and not just the classical N/P/K nutrients, group with microbial community changes, and alterations in the microbiome can be seen across different soil fertility types. Root endosphere emerged as the plant microhabitat more affected by this rhizobial efficiency-driven community reshaping, manifested by the accumulation of members of the phylum Actinobacteria. The plant in turn plays an active role in regulating its root community, including sanctioning low nitrogen efficiency rhizobial strains, leading to nodule senescence in particular plant-soil-rhizobia strain combinations. CONCLUSIONS: The microbiome-soil-rhizobial dynamic strongly influences plant nutrient uptake and growth, with the endosphere and rhizosphere shaped differentially according to plant-rhizobial interactions with strains that vary in nitrogen-fixing efficiency levels. These results open up the possibility to select inoculation partners best suited for plant, soil type and microbial community. Video Abstract.


Assuntos
Medicago truncatula , Rhizobium , Sinorhizobium meliloti , Fixação de Nitrogênio/fisiologia , Medicago truncatula/microbiologia , Sinorhizobium meliloti/fisiologia , Simbiose/fisiologia
6.
Heliyon ; 9(3): e14093, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36923885

RESUMO

Gout is an arthropathic and inflammatory disease. The prevalence and incidence of such disease has risen in last decades. It is associated with life style thus it could be recognize as life style diseases. In the present study, the flower extract of Alstonia scholaris Linn R.Br., Flower was initially subjected to extraction, isolation which leads to purification of pure eight compounds. All these compounds were identified using various spectroscopic techniques. In-vitro Xanthine oxidase inhibition activity was performed to determine the antigout potential of lead compounds. Compound 8 showed significant activity among all i.e. 14.7 ± 0.43 as compare to standard allopurinol 6.77 ± 0.26. Accordingly, in-silico studies using Autodock vina 4 showed the ligand-protein interaction of luteolin with 3AX7. The docking simulations showed significant binding pocket sites of respective proteins 3AX7 with the least binding energy -10.2 kcal/mol. Consequently, molecular docking simulations for 100ns indicated robust evidence with their conformational structural interaction which serve as active sites for Lead compound. Principal Component Analysis indicated first three PCs capture 23.8%, 39%, and 49% of structural variance in protein. Therefore compound 8 could be consider for potential drug design and development in gout therapy.

7.
PLoS One ; 18(2): e0282109, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36827253

RESUMO

Low-carbon pilot policies are an important way to achieve the goal of "peak carbon neutrality" and are of great significance to China's international commitments. Based on a sample of 282 prefecture-level cities from 2006 to 2020, this paper investigates the impact of low-carbon pilot policies on urban carbon efficiency using a quasi-natural experiment with three batches of low-carbon pilot cities in 2010, 2012, and 2017, respectively. It is found that: (1) low-carbon pilot cities can improve urban carbon emission efficiency, which is still valid after a series of robustness tests such as the parallel trend test, placebo test, PSM-DID, and counterfactual test; (2) low-carbon pilot cities can enhance urban carbon emission efficiency by promoting the level of urban innovation and advanced urban industrial structure; and (3) the impact of low-carbon pilot policies on urban carbon emission efficiency is heterogeneous across cities with different geographical locations, population sizes, and resource endowment types. The findings provide policy insights for the promotion of low-carbon pilot policies and strengthening the construction of low-carbon pilot cities.


Assuntos
Carbono , Indústrias , Cidades , China , Políticas
8.
Front Psychol ; 13: 912519, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405207

RESUMO

The premise of this study is to look at the intergenerational transferal of language and racial trauma of Asian immigrants in general and Korean-American immigrants in particular to a western country, the United States of America. This study investigates trauma from a psychological standpoint, based on Chang-Rae Lee's novel Native Speaker. In describing a marker of citizenship, the novel's title also points to who is the native language speaker and who is a native of a country, and why one who is not may be excluded. The Korean immigrants' vulnerability to the English language and racial differences highlights their status as minority "others," and they suffer from transgenerational trauma. As a result of transgenerational traumatic effects, Henry (the protagonist) has various traumatic side effects such as dysphasia, aphasia, and parasomnia and finally leaves no stone unturned to recuperate from trauma. The Trauma of the Unspeakable theory by Michelle Balaev is used in this article to show how trauma affects people's minds.

9.
Plant Cell Environ ; 45(10): 3001-3017, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35892221

RESUMO

Microbe-associated molecular pattern (MAMP)-triggered immunity (MTI) research has traditionally centred around signal transduction pathways originating from activated membrane-localized pattern recognition receptors (PRRs), culminating in nuclear transcription and posttranslational modifications. More recently, chloroplasts have emerged as key immune signalling hubs, playing a central role in integrating environmental signals. Notably, MAMP recognition induces chloroplastic reactive oxygen species (cROS) that is suppressed by pathogen effectors, which also modify the balance of chloroplast-synthesized precursors of the defence hormones, jasmonic acid, salicylic acid (SA) and abscisic acid. This study focuses on how well-characterized PRRs and coreceptors modulate chloroplast physiology, examining whether diverse signalling pathways converge to similarly modulate chloroplast function. Pretreatment of receptor mutant plants with MAMP and D(Damage)AMP peptides usually protect against effector modulation of chlorophyll fluorescence and prevent Pseudomonas syringae effector-mediated quenching of cROS and suppression of maximum dark-adapted quantum efficiency (the ratio of variable/maximum fluorescence [Fv /Fm ]). The MTI coreceptor double mutant, bak1-5/bkk1-1, exhibits a remarkable decrease in Fv /Fm compared to control plants during infection, underlining the importance of MTI-mediated signalling in chloroplast immunity. Further probing the role of the chloroplast in immunity, we unexpectedly found that even moderate changes in light intensity can uncouple plant immune signalling.


Assuntos
Cloroplastos , Pseudomonas syringae , Cloroplastos/metabolismo , Doenças das Plantas , Imunidade Vegetal , Plantas/metabolismo , Pseudomonas syringae/fisiologia , Receptores de Reconhecimento de Padrão/metabolismo , Ácido Salicílico/metabolismo , Estresse Fisiológico
10.
Microsc Res Tech ; 85(8): 2848-2856, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35488419

RESUMO

Eclipta alba (L.) is a valuable medicinal plant. However, its medicinal efficacy can be affected by geminivirus infection. Therefore, identification of healthy specimen is essential before to use as medicine. The present study provided the taxonomic characterization of geminivirus infected and healthy E. alba plant by studying apparent morphology and microscopic features through light and scanning electron microscopy. Before taxonomic characterization infected and healthy specimens were separated through molecular detection of geminivirus. Results of morphological studies reported that geminivirus infected E. alba plant showed systematic symptoms of infection like stunted growth, distortion and chlorosis of leaves, decrease in size of root, shoot and fruit, and so forth in comparison to healthy specimen. Anatomical findings reported that in both plants anomocytic and anisocytic types of stomata with multicellular warty trichomes were present. However, variations were observed in quantitative measures such as size of trichomes, epidermal, subsidiary and guard cells. Palynological observations identifies that both plants possessed tricolporate type of pollen but variation was mainly observed in size and shape of pollen, thickness of exine and intine, P/E ratio, pore size, interspecific difference, size of colpi, and pollen ornamentation. Overall this study concluded that both healthy and infected E. alba do not reported much variations in qualitative taxonomic features, but can be differentiated in terms of quantitative taxonomic evidences. Future studies are recommended for pharmacological analysis of both healthy and virus infected plants. RESEARCH HIGHLIGHTS: Eclipta alba has incredible therapeutic worth, but due to geminivirus infection the plant is affecting badly. Hence, the present studies give a comprehensive taxonomic report on the geminivirus infected and healthy plant species.


Assuntos
Eclipta , Geminiviridae , Elétrons , Microscopia Eletrônica de Varredura , Tricomas/ultraestrutura
11.
Pak J Pharm Sci ; 35(1(Supplementary)): 219-225, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35228180

RESUMO

A polyphenolic flavone Luteolin (3',4',5,7-tetrahydroxyflavone) is found in various plants and is traditionally used in Chinese medicine. It is obtained from Alstonia scholaris (L.) R.Br Flower belonging to the family Apocynaceae while investigation. Various studies have been demonstrated the antioxidant or antiulcer potential of luteolin from different plant sources. In the present investigation the antioxidant or antiulcer effect of the Luteolin has been carried out using molecular docking simulations. The objective of this study was to analyze the antioxidant and antiulcer potential of luteolin obtained during isolation. The in vitro biological evaluation has been supported by the in silico studies using Autodock vina 4 shows the ligand-protein interaction of lute olin with 1HD2, 4GY7 and 3O1Q. Luteolin showed significant DPPH scavenging and urease inhibition activity i.e., 23.4 ± 0.87, 6.21±0.45 IC50 (uM) respectively as compared to the standard BHA and thiourea 44.2±0.45, 22.4±0.29 IC50 (uM) respectively. The docking simulations showed significant binding pocket sites with the respective proteins1HD2, 4GY7 and 3O1Q with the least binding energy -6.8, -8.0 and -8.2 kcal/mol respectively. Thus, Strong evidence has been presented with their confirmation structural interaction via molecular docking with proteins that serve as binding sites for available Luteolin molecule. The findings justify the application of the compound as a novel antioxidant and antiulcer agent.


Assuntos
Alstonia/química , Luteolina/farmacologia , Compostos Fitoquímicos/farmacologia , Urease/antagonistas & inibidores , Compostos de Bifenilo , Sequestradores de Radicais Livres , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Luteolina/química , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Compostos Fitoquímicos/química , Picratos
12.
Microsc Res Tech ; 85(6): 2277-2281, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35178821

RESUMO

The current study was embraced to examine the morphoanatomical distinguishing proof utilizing light microscopy (LM), scanning electron microscopy (SEM) and antibacterial activities of turmeric extract utilizing amoxicillin and ciprofloxacin. Cross over part of the rhizome is roundabout in structure. The peripheral layer is the periderm which comprises of 6-7 layers of digressively lengthened cells. This is trailed by an expansive cortex made of flimsy walled parenchyma cells with intercellular spaces. The antibacterial activities of turmeric extract in blend with drug items like amoxicillin and ciprofloxacin was likewise examined at various fixations. Different turmeric samples and drug items were gathered from various shops of Lahore. The samples were analyzed for antibacterial activities by utilizing pour plate method. In general outcomes showed fundamentally higher zone of inhibition of turmeric extract in combination with ciprofloxacin and lower zone of inhibition of turmeric extract in combination with amoxicillin. It is inferred that turmeric extract have hostile impact in blend with amoxicillin. Thus, the combination of turmeric extract with antimicrobial (amoxicillin) diminished the intensity of antibiotic. The turmeric extract have more antibacterial activity in mix with ciprofloxacin. Thus, the blend of turmeric extract with antibiotic (ciprofloxacin) expanded the intensity of antibiotic. RESEARCH HIGHLIGHTS: Morphoanatomical study of Turmeric rhizome using light microscopy (LM) and scanning electron microscopy (SEM). The antibacterial activities of turmeric extract like amoxicillin and ciprofloxacin was also investigated at different concentrations.


Assuntos
Curcuma , Rizoma , Amoxicilina , Antibacterianos/farmacologia , Ciprofloxacina/análise , Ciprofloxacina/farmacologia , Curcuma/química , Microscopia Eletrônica de Varredura , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Rizoma/química
13.
Plant J ; 110(1): 71-87, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34978355

RESUMO

A typical adaptive response to submergence regulated by SUB1A, the ethylene-responsive transcription factor gene, is the restricted elongation of the uppermost leaves. However, the molecular and physiological functions of SUB1A have been characterized using entire shoot tissues, most of which are mature leaves that do not elongate under submergence. We aimed to identify leaf-type-specific and overlapping adaptations coordinated in SUB1A-dependent and -independent manners. To this end, we compared the transcriptomic and hormonal responses to submergence between mature and growing leaves using rice genotypes with and without SUB1A. Monosaccharide, branched-chain amino acid, and nucleoside metabolism, associated with ATP synthesis, were commonly activated in both leaf types regardless of genotype. In both leaf types, pathways involved in carbohydrate and nitrogen metabolism were suppressed by SUB1A, with more severe restriction in growing leaves that have a greater energy demand if SUB1A is absent. In growing leaves, accumulation of and responsiveness to growth-regulating hormones were properly modulated by SUB1A, which correlated with restricted elongation. In mature leaves, submergence-induced auxin accumulation was suppressed by SUB1A. This study demonstrates that different sets of hormonal pathways, both of which are modulated by SUB1A, contribute to distinct adaptive responses to submergence in mature and growing rice leaves.


Assuntos
Oryza , Adaptação Fisiológica/genética , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
Front Public Health ; 10: 1035536, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684943

RESUMO

Global health governance is a developing system in this complex institutional regime. The local and regional health policies sometimes challenge global health governance due to diverse discourse in various countries. In the wake of COVID-19, global health governance was reaffirmed as indifferent modules to control and eliminate the pandemic; however, the global agencies later dissected their own opinion and said that "countries must learn to live with a pandemic." Given the controversial statement, this research focuses on the strong and effective policies of the Russian Federation, Pakistan, and China. The research uses the law and governance results and newly developed policies of the three countries formed under the global health policies. The conclusion is based on the statement that in order to live with the pandemic, strong health measures are required at each level.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , Paquistão/epidemiologia , Política de Saúde , Saúde Global , China/epidemiologia
15.
Front Psychol ; 13: 1104178, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36704695

RESUMO

This study empirically investigates the moderating effect of board activeness on the relationship between the structure of corporate ownership and firm performance. The objective was evaluated using the hierarchal panel regressions with data from non-financial companies of the Pakistan Stock Exchange from 2009 to 2018, operationalizing the ownership structure as state ownership, associated companies, foreign ownership, ownership concentration, institutional ownership, and family ownership, and firm performance as operating performance, financial performance, and stock market performance. The findings of the study revealed that operating, financial, and stock market performance were favorably influenced by the ownership stakes of the state, associated concerns, institutions, and foreigners. Family interests proved to be diverse for the firm performance. The isolated effect of the board consistently uplifted the firm productivity, but its interactional impact with all the ownership stakeholders postulated differential outcomes for internal and external performance. The study provides valuable insights for policymakers and investors to make optimal strategies to manage ownership interests and enhance value.

16.
Glob Ment Health (Camb) ; 9: 115-122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618756

RESUMO

Background: Prevalence of post-traumatic stress disorder (PTSD) is high in Pakistan both due to natural disasters and ongoing conflicts. Offspring of trauma survivors are at increased risk for mental and physical illnesses. Parental PTSD has been linked to troubled parent-child relationships, behaviour problems, trauma symptoms, and depression in children. This study aims to explore the acceptability, feasibility and indications of the effectiveness of group learning through play plus trauma-focused cognitive behaviour therapy (LTP Plus TF-CBT) for parents experiencing PTSD. Methods/Design: This is a two-arm pilot cluster randomised controlled trial (RCT). We aim to recruit 300 parents with a diagnosis of PTSD. The screening will be done using the Impact of Event Scale-Revised. Diagnosis of PTSD will be confirmed using the Clinician-Administered PTSD Scale-5 (CAPS-5). Union Councils from Peshawar and Karachi will be randomised into either group LTP Plus TF CBT arm or treatment as usual (TAU). The intervention includes 12 sessions of LTP Plus TF-CBT delivered weekly in the first 2 months and then fortnightly in a group setting by trained psychologists. The groups will be co-facilitated by the community health workers (CHWs). Parents will be assessed at baseline and 4th month (end of the intervention), using the Patient Health Questionnaire (PHQ-9), Generalised Anxiety Disorder (GAD-7) Scale, Client Service Receipt Inventory (CSRI), and Ages and Stages Questionnaire (ASQ-3). Discussion: This trial would help build an understanding of the acceptability, feasibility and indications of the effectiveness of a low-cost parenting intervention.

17.
Pak J Pharm Sci ; 34(2(Supplementary)): 747-753, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34275810

RESUMO

Non-steroidal anti-inflammatory drugs (NSAIDs) are frequently used for the treatment and prevention of inflammation with the increase in number of side effects. Traditional plants have been used to treat inflammation owing to lesser adverse responses. Croton bonplandianus being an anti-inflammatory plant is extensively utilized all over the world. The methanolic and aqueous leaves extracts of Croton bonplandianus were exposed to anti-inflammatory activity in the carrageenan induced paw edema against standard diclofenac sodium, followed by the histopathlogical examination. The highest dose of methanolic extract were shown significant anti-inflammatory action having a significant P-value (P<0.05-0.001) compared with the diclofenac sodium (P<0.01-0.001) and aqueous extracts (P<0.5-0.01). The histopathological examination illustrated the vasodialation with reduction in the intensity of edema, neutrophils infiltration and other inflammatory cells. C. bonplandianus being a reactive oxygen species scavenger, responsible to exert an excellent anti-inflammatory activity. The present study confirmed the anti-inflammatory potential of drug extracts and authors recommended its utilization in the treatment of pain, inflammation and relevant diseases in future. However, phytochemical screening is to be required for the complete evaluation of active chemical constituent (s).


Assuntos
Anti-Inflamatórios/farmacologia , Croton/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Croton/efeitos adversos , Diclofenaco/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/tratamento farmacológico , Edema/patologia , Masculino , Folhas de Planta/efeitos adversos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
18.
Front Plant Sci ; 9: 930, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30057584

RESUMO

Arabidopsis PR1 is a salicylic acid (SA) inducible marker gene for systemic acquired resistance (SAR). However, the regulation of PR1 in plants is poorly understood. In this study, we showed that AtWRKY50 transcription factor binds to two promoter elements of PR1 via its DNA binding domain. Interestingly, the DNA-binding sites for AtWRKY50 deviate significantly from the consensus WRKY binding W-box. The binding sites are located in close proximity to the binding sites for TGA transcription factors. Transactivation experiments in Arabidopsis protoplasts derived from wild type, npr1-1 and tga256 mutant plants indicated that AtWRKY50 alone was able to induce expression of a PR1::ß-glucuronidase (GUS) reporter gene, independent of TGAs or NPR1. However, co-expression of TGA2 or TGA5 with AtWRKY50 synergistically enhanced expression to high levels. Yeast-2-hybrid assays and bimolecular fluorescence complementation (BiFC) experiments revealed that AtWRKY50 could interact with TGA2 and TGA5. Using electrophoretic mobility shift assays (EMSA) it was established that AtWRKY50 and TGA2 or TGA5 simultaneously bind to the PR1 promoter. Taken together, these results support a role of AtWRKY50 in SA-induced expression of PR1. Highlights: AtWRKY50 specifically binds to LS10 region of PR1 promoter and interacts with TGAs to synergistically activate PR1 expression.

19.
PLoS One ; 13(7): e0199248, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30028850

RESUMO

The homeodomain-leucine zipper (HD-Zip) transcription factor family plays vital roles in plant development and morphogenesis as well as responses to biotic and abiotic stresses. In barley, a recessive mutation in Vrs1 (HvHox1) changes two-rowed barley to six-rowed barley, which improves yield considerably. The Vrs1 gene encodes an HD-Zip subfamily I transcription factor. Phylogenetic analysis has shown that the rice HD-Zip I genes Oshox12 and Oshox14 are the closest homologues of Vrs1. Here, we show that Oshox12 and Oshox14 are ubiquitously expressed with higher levels in developing panicles. Trans-activation assays in yeast and rice protoplasts demonstrated that Oshox12 and Oshox14 can bind to a specific DNA sequence, AH1 (CAAT(A/T)ATTG), and activate reporter gene expression. Overexpression of Oshox12 and Oshox14 in rice resulted in reduced panicle length and a dwarf phenotype. In addition, Oshox14 overexpression lines showed a deficiency in panicle exsertion. Our findings suggest that Oshox12 and Oshox14 may be involved in the regulation of panicle development. This study provides a significant advancement in understanding the functions of HD-Zip transcription factors in rice.


Assuntos
DNA de Plantas/genética , Regulação da Expressão Gênica de Plantas , Hordeum/genética , Oryza/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , DNA de Plantas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Hordeum/classificação , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Inflorescência/genética , Inflorescência/crescimento & desenvolvimento , Inflorescência/metabolismo , Zíper de Leucina , Oryza/classificação , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Filogenia , Desenvolvimento Vegetal/genética , Proteínas de Plantas/metabolismo , Ligação Proteica , Protoplastos/metabolismo , Fatores de Transcrição/metabolismo
20.
Methods Mol Biol ; 1761: 165-175, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29525956

RESUMO

Cell type-specific marker lines expressing fluorophores such as GFP or GUS can be used as starting material from which single cell types can be isolated by fluorescence-activated cell sorting (FACS) and/or for the study of root development. Establishing the stability of these lines is an essential step prior to further study to ensure that marker expression and localization is stable over time and during environmental perturbations of interest to researchers applying these lines as treatments. Here, we detail the use of root cross sectioning to investigate marker expression throughout the length and width of the root using the model legume Medicago truncatula as an example. In order to deal with the fact that plant cell walls are highly autofluorescent, we also describe the usage of confocal microscopy to conduct a lambda scan to discriminate autofluorescence from marker molecule expression.


Assuntos
Citometria de Fluxo , Expressão Gênica , Genes Reporter , Histocitoquímica , Desenvolvimento Vegetal , Raízes de Plantas/citologia , Raízes de Plantas/genética , Microscopia Confocal , Especificidade de Órgãos , Desenvolvimento Vegetal/genética , Raízes de Plantas/metabolismo
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