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1.
Langmuir ; 40(36): 18837-18856, 2024 Sep 10.
Article de Anglais | MEDLINE | ID: mdl-39207273

RÉSUMÉ

In contrast to traditional static surfaces, smart patterned surfaces with periodical and reversible morphologies offer limitless opportunities for encoding surface functions and properties on demand, facilitating their widespread application as functional building blocks in various devices. Advances in intelligently controlling the macroscopic properties of these smart surfaces have been accomplished through various techniques (such as three-dimensional printing, imprint lithography and femtosecond laser) and responsive materials. In contrast to the sophisticated techniques above, dynamic anisotropic wrinkling, taking advantage of dynamic programmable manipulation of surface wrinkling and its orientation, offers a powerful alternative for fabricating dynamic periodical patterns due to its spontaneous formation, versatility, convenient scale-up fabrication, and sensitivity to various stimuli. This review comprehensively summarizes recent advances in smart patterned surfaces with dynamic oriented wrinkles, covering design principles, fabrication techniques, representative types of physical and chemical stimuli, as well as fine-tuning of wrinkle dimensions and orientation. Finally, advanced applications of these smart patterned surfaces are presented, along with a discussion of current challenges and future prospects in this rapidly evolving field. This review would offer some insights and guidelines for designing and engineering novel stimuli-responsive smart wrinkled surfaces, thereby facilitating their sustainable development and progressing toward commercialization.

2.
Cogn Emot ; : 1-12, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38953391

RÉSUMÉ

Previous research on emotion-induced blindness (EIB) argues emotional distractors capture attention in a bottom-up manner due to their physical and emotional salience. However, recent research has shown it is controversial whether EIB will be modulated by top-down factors. The present study further investigated whether the magnitude of EIB would be modulated by top-down factors, specifically the emotional relevance between tasks and distractors. Participants were divided into two groups having the same targets except for different task instructions. The orientation judgment group was asked to judge the orientation of the target (an emotionally irrelevant task), and the emotion judgment group was required to judge the emotional valence of the target (an emotionally relevant task). It was found the emotional relevance between tasks and distractors has no modulation on the magnitudes of EIB in two groups when targets and distractors are from different categories (Experiment 1), but a modulation when they are from the same category (Experiment 2). Consequently, we contend top-down task relevance modulates the EIB effect and distractors' priority is regulated by the emotional relevance between tasks and distractors. The current study holds attentional capture by stimulus-driven is unconditional in EIB, while attentional capture by goal-driven requires certain conditions.

3.
Front Microbiol ; 13: 951830, 2022.
Article de Anglais | MEDLINE | ID: mdl-36016772

RÉSUMÉ

The novel protein MclX (mother cell lysis X) in Bacillus thuringiensis subsp. kurstaki strain HD73 (B. thuringiensis HD73) was characterized in this work. MclX has no known domain and its gene deletion in HD73 resulted in Cry1Ac encapsulation in the mother cell and did not influence Cry1Ac protein production or insecticidal activity. In vitro cell wall hydrolysis experiments showed that MclX cannot hydrolyze the cell wall. In mclX deletion mutants, the expression of cwlC (which encodes a key cell wall hydrolase) was significantly decreased, as shown by the ß-galactosidase activity assay. MclX cannot directly bind to the cwlC promoter, based on the electrophoretic mobility shift assay (EMSA). The cwlC was reported to be regulated by σK and GerE. However, the transcriptional activities of sigK and gerE showed no difference between HD73 and the mclX deletion mutant. It is indicated that MclX influenced cwlC expression independently of σK or GerE, through a new pathway to regulate cwlC expression. mclX deletion could be a new approach for insecticidal protein encapsulation in Bacillus thuringiensis.

4.
Front Psychol ; 13: 920920, 2022.
Article de Anglais | MEDLINE | ID: mdl-35664156

RÉSUMÉ

Contemporarily, depression has become a common psychiatric disorder that influences people's life quality and mental state. This study presents a systematic review analysis of depression based on a hierarchical structure approach. This research provides a rich theoretical foundation for understanding the hot spots, evolutionary trends, and future related research directions and offers further guidance for practice. This investigation contributes to knowledge by combining robust methodological software for analysis, including Citespace, Ucinet, and Pajek. This paper employed the bibliometric methodology to analyze 5,000 research articles concerning depression. This current research also employed the BibExcel software to bibliometrically measure the keywords of the selected articles and further conducted a co-word matrix analysis. Additionally, Pajek software was used to conduct a co-word network analysis to obtain a co-word network diagram of depression. Further, Ucinet software was utilized to calculate K-core values, degree centrality, and mediated centrality to better present the research hotspots, sort out the current status and reveal the research characteristics in the field of depression with valuable information and support for subsequent research. This research indicates that major depressive disorder, anxiety, and mental health had a high occurrence among adolescents and the aged. This present study provides policy recommendations for the government, non-governmental organizations and other philanthropic agencies to help furnish resources for treating and controlling depression orders.

5.
Microbiol Spectr ; 9(2): e0088121, 2021 10 31.
Article de Anglais | MEDLINE | ID: mdl-34612699

RÉSUMÉ

Sporulation is an important part of the life cycle of Bacillus thuringiensis and the basis for the production of parasporal crystals. This study identifies and characterizes two homologous spoVS genes (spoVS1 and spoVS2) in B. thuringiensis, both of whose expression is dependent on the σH factor. The disruption of spoVS1 and spoVS2 resulted in defective B. thuringiensis sporulation. Similar to Bacillus subtilis, B. thuringiensis strain HD(ΔspoVS1) mutants showed delayed formation of the polar septa, decreased sporulation efficiency, and blocked spore release. Different from B. subtilis, B. thuringiensis HD(ΔspoVS1) mutants had disporic septa and failed to complete engulfment in some cells. Moreover, HD(ΔspoVS2) mutants had delayed spore release. The effect of spoVS1 deletion on polar septum delay and sporulation efficiency could be compensated by spoVS2. ß-Galactosidase activity analysis showed that the expression of pro-sigE and spoIIE decreased to different degrees in the HD(ΔspoVS1) and HD(ΔspoVS2) mutants. The different effects of the two mutations on the expression of sporulation genes led to decreases in Cry1Ac production of different levels. IMPORTANCE There is only one spoVS gene in B. subtilis, and its effects on sporulation have been reported. In this study, two homologous spoVS genes were found and identified in B. thuringiensis. The different effects on sporulation and parasporal crystal protein production in B. thuringiensis and their relationship were investigated. We found that these two homologous spoVS genes are highly conserved in the Bacillus cereus group, and therefore, the functional characterization of SpoVS is helpful to better understand the sporulation processes of members of the Bacillus cereus group.


Sujet(s)
Toxines de Bacillus thuringiensis/biosynthèse , Bacillus thuringiensis/génétique , Protéines bactériennes/génétique , Protéines bactériennes/métabolisme , Endotoxines/biosynthèse , Hémolysines/biosynthèse , Spores bactériens/croissance et développement , Bacillus thuringiensis/croissance et développement , Délétion de gène , Régulation de l'expression des gènes bactériens/génétique , Facteur sigma/génétique , Facteur sigma/métabolisme
6.
Microbiol Spectr ; 9(1): e0007521, 2021 09 03.
Article de Anglais | MEDLINE | ID: mdl-34319140

RÉSUMÉ

Bacillus thuringiensis secreted insecticidal proteins (Sip) are a secretion that is toxic to coleopteran pests. However, the transcriptional mechanism of sip genes is still unknown. The transcriptional regulation of the sip1Ab1 gene and the expression of the Sip1Ab1 protein were investigated in this study. The results demonstrated that the secretion of the Sip1Ab1 protein in HD73 was almost the same as that in the original QZL38 strain during the transition phase. Analysis of the ß-galactosidase activities of sip1Ab1-lacZ in both the HD73 and abrB mutant strains indicated that the transcription of sip1Ab1 is dependent on AbrB. Electrophoretic mobility shift assays showed that AbrB could bind with the sip1Ab1 promoter, and two binding sites of AbrB in the region of the promoter of sip1Ab1 were determined by DNase I footprinting assays. All of the above-described results proved that AbrB positively regulates the sip1Ab1 gene. IMPORTANCE Bacillus thuringiensis Sip proteins are secreted insecticidal toxins that are toxic to coleopteran pests. In this study, we investigated the transcriptional mechanism of the sip gene and showed strong evidence that Sip1Ab1 is secreted in the transition phase and that AbrB, a transition phase regulator that is usually a repressor, positively and directly regulates sip1Ab1. Reports of AbrB positive regulation are rare, even in Bacillus subtilis. To the best of our knowledge, no toxic gene has been reported to be positively regulated by AbrB in Bacillus species.


Sujet(s)
Toxines de Bacillus thuringiensis/génétique , Bacillus thuringiensis/métabolisme , Protéines bactériennes/métabolisme , Endotoxines/génétique , Régulation de l'expression des gènes bactériens , Hémolysines/génétique , Facteurs de transcription/métabolisme , Bacillus thuringiensis/génétique , Toxines de Bacillus thuringiensis/métabolisme , Protéines bactériennes/génétique , Séquence nucléotidique , Sites de fixation , Endotoxines/métabolisme , Hémolysines/métabolisme , Régions promotrices (génétique) , Facteurs de transcription/génétique
7.
Appl Microbiol Biotechnol ; 103(4): 1617-1626, 2019 Feb.
Article de Anglais | MEDLINE | ID: mdl-30617537

RÉSUMÉ

Bacillus thuringiensis is a gram-positive, spore-forming bacterium that produces insecticidal crystal proteins during sporulation. The production of these crystals results primarily from the expression of cry genes. In this review, we focus on the expression and application of cry genes directed by both cry gene promoters and non-cry gene promoters in different hosts. However, not all cry genes and niches are compatible with B. thuringiensis. New delivery systems offsetting the current limitations in B. thuringiensis application are needed to improve Cry production, niche fitness, and persistence. This review examines currently available research and highlights areas in need of further research and development for more effective production and utilization of Cry insecticidal proteins.


Sujet(s)
Bacillus thuringiensis/génétique , Bacillus thuringiensis/métabolisme , Protéines bactériennes/biosynthèse , Biotechnologie/méthodes , Endotoxines/biosynthèse , Expression des gènes , Hémolysines/biosynthèse , Toxines de Bacillus thuringiensis , Protéines bactériennes/génétique , Endotoxines/génétique , Hémolysines/génétique
8.
Biochem Biophys Res Commun ; 501(2): 598-604, 2018 06 22.
Article de Anglais | MEDLINE | ID: mdl-29753738

RÉSUMÉ

Glucosinolates are a class of amino acid-derived specialized metabolites characteristic of the Brassicales order. Trp derived indolic glucosinolates are essential for the effective plant defense responses to a wide range of pathogens and herbivores. In Arabidopsis, MYB51 is the key transcription factor positively regulates indolic glucosinolate production by activating certain biosynthetic genes. In this study, we report the isolation and identification of a MYB51 from broccoli designated as BoMYB51. Overexpression of BoMYB51 in Arabidopsis increased indolic glucosinolate production by upregulating biosynthetic genes and resulted in enhanced flagellin22 (Flg22) induced callose deposition. The spatial expression pattern and responsive expression of BoMYB51 to several hormones and stress treatments were investigated by expressing the ß-glucuronidase (GUS) reporter gene driven by BoMYB51 promotor in Arabidopsis and quantitative real-time PCR analysis in broccoli. Our study provides information on molecular characteristics of BoMYB51 and possible physiological process BoMYB51 may involve.


Sujet(s)
Brassica/génétique , Régulation de l'expression des gènes végétaux , Glucosinolates/génétique , Protéines végétales/génétique , Facteurs de transcription/génétique , Arabidopsis/génétique , Arabidopsis/métabolisme , Voies de biosynthèse , Brassica/métabolisme , Clonage moléculaire , Gènes de plante , Glucosinolates/métabolisme , Protéines végétales/métabolisme , Facteurs de transcription/métabolisme
9.
Front Plant Sci ; 7: 1292, 2016.
Article de Anglais | MEDLINE | ID: mdl-27621741

RÉSUMÉ

Glucosinolates, a class of secondary metabolites from cruciferous plants, are derived from amino acids and have diverse biological activities, such as in biotic defense, depending on their side chain modification. The first structural modification step in the synthesis of aliphatic (methionine-derived) glucosinolates-S-oxygenation of methylthioalkyl glucosinolates to methylsulfinylalkyl glucosinolates-was found to be catalyzed by five flavin-containing monooxygenases (FMOs), FMOGS-OX1-5. Here, we report two additional FMOGS-OX enzymes, FMOGS-OX6, and FMOGS-OX7, encoded by At1g12130 and At1g12160, respectively. The overexpression of both FMOGS-OX6 and FMOGS-OX7 decreased the ratio of methylthioalkyl glucosinolates to the sum of methylthioalkyl and methylsulfinylalkyl glucosinolates, suggesting that the introduction of the two genes converted methylthioalkyl glucosinolates into methylsulfinylalkyl glucosinolates. Analysis of expression pattern revealed that the spatial expression of the two genes is quite similar and partially overlapped with the other FMOGS-OX genes, which are primarily expressed in vascular tissue. We further analyzed the responsive expression pattern of all the seven FMOGS-OX genes to exogenous treatment with abscisic acid, 1-aminocyclopropane-1-carboxylic acid (ACC), jasmonic acid (JA), salicylic acid, indole-3-acetic acid (IAA), and low and high temperatures. Although these genes showed same tendency toward the changing stimulus, the sensitivity of each gene was quite different. The variety in spatial expression among the FMOGS-OX genes while responding to environmental stimulus indicated a complex and finely tuned regulation of glucosinolates modifications. Identification of these two novel FMOGS-OX enzymes will enhance the understanding of glucosinolates modifications and the importance of evolution of these duplicated genes.

10.
Plant J ; 86(6): 514-29, 2016 06.
Article de Anglais | MEDLINE | ID: mdl-27121031

RÉSUMÉ

Although research has extensively illustrated the molecular basis of plant responses to salt and high-pH stresses, knowledge on carbonate alkaline stress is poor and the specific responsive mechanism remains elusive. We have previously characterized a Glycine soja Ca(2+) /CAM-dependent kinase GsCBRLK that could increase salt tolerance. Here, we characterize a methionine sulfoxide reductase (MSR) B protein GsMSRB5a as a GsCBRLK interactor by using Y2H and BiFc assays. Further analyses showed that the N-terminal variable domain of GsCBRLK contributed to the GsMSRB5a interaction. Y2H assays also revealed the interaction specificity of GsCBRLK with the wild soybean MSRB subfamily proteins, and determined that the BoxI/BoxII-containing regions within GsMSRBs were responsible for their interaction. Furthermore, we also illustrated that the N-terminal basic regions in GsMSRBs functioned as transit peptides, which targeted themselves into chloroplasts and thereby prevented their interaction with GsCBRLK. Nevertheless, deletion of these regions allowed them to localize on the plasma membrane (PM) and interact with GsCBRLK. In addition, we also showed that GsMSRB5a and GsCBRLK displayed overlapping tissue expression specificity and coincident expression patterns under carbonate alkaline stress. Phenotypic experiments demonstrated that GsMSRB5a and GsCBRLK overexpression in Arabidopsis enhanced carbonate alkaline stress tolerance. Further investigations elucidated that GsMSRB5a and GsCBRLK inhibited reactive oxygen species (ROS) accumulation by modifying the expression of ROS signaling, biosynthesis and scavenging genes. Summarily, our results demonstrated that GsCBRLK and GsMSRB5a interacted with each other, and activated ROS signaling under carbonate alkaline stress.


Sujet(s)
Fabaceae/enzymologie , Fabaceae/métabolisme , Methionine Sulfoxide Reductases/métabolisme , Protéines végétales/métabolisme , Arabidopsis/métabolisme , Calcium-Calmodulin-Dependent Protein Kinases/génétique , Calcium-Calmodulin-Dependent Protein Kinases/métabolisme , Calmoduline/génétique , Calmoduline/métabolisme , Protéines de liaison à la calmoduline/génétique , Protéines de liaison à la calmoduline/métabolisme , Fabaceae/génétique , Régulation de l'expression des gènes végétaux , Methionine Sulfoxide Reductases/génétique , Protéines végétales/génétique , Liaison aux protéines , Espèces réactives de l'oxygène/métabolisme
11.
Plant Mol Biol ; 90(4-5): 419-34, 2016 Mar.
Article de Anglais | MEDLINE | ID: mdl-26801329

RÉSUMÉ

It is widely accepted that Ca(2+)ATPase family proteins play important roles in plant environmental stress responses. However, up to now, most researches are limited in the reference plants Arabidopsis and rice. The function of Ca(2+)ATPases from non-reference plants was rarely reported, especially its regulatory role in carbonate alkaline stress responses. Hence, in this study, we identified the P-type II Ca(2+)ATPase family genes in soybean genome, determined their chromosomal location and gene architecture, and analyzed their amino acid sequence and evolutionary relationship. Based on above results, we pointed out the existence of gene duplication for soybean Ca(2+)ATPases. Then, we investigated the expression profiles of the ACA subfamily genes in wild soybean (Glycine soja) under carbonate alkaline stress, and functionally characterized one representative gene GsACA1 by using transgenic alfalfa. Our results suggested that GsACA1 overexpression in alfalfa obviously increased plant tolerance to both carbonate alkaline and neutral salt stresses, as evidenced by lower levels of membrane permeability and MDA content, but higher levels of SOD activity, proline concentration and chlorophyll content under stress conditions. Taken together, for the first time, we reported a P-type II Ca(2+)ATPase from wild soybean, GsACA1, which could positively regulate plant tolerance to both carbonate alkaline and neutral salt stresses.


Sujet(s)
Calcium-Transporting ATPases/métabolisme , Fabaceae/enzymologie , Régulation de l'expression des gènes codant pour des enzymes/physiologie , Régulation de l'expression des gènes végétaux/physiologie , Chlorure de sodium/toxicité , Stress physiologique/physiologie , Séquence d'acides aminés , Calcium-Transporting ATPases/génétique , Carbonates/toxicité , Évolution moléculaire , Fabaceae/génétique , Fabaceae/métabolisme , Concentration en ions d'hydrogène , Données de séquences moléculaires , Famille multigénique , Phylogenèse , Protéines végétales/génétique , Protéines végétales/métabolisme
12.
Materials (Basel) ; 9(2)2016 Jan 25.
Article de Anglais | MEDLINE | ID: mdl-28787868

RÉSUMÉ

Individual Carbon Nanotubes (CNTs) have a great mechanical strength that needs to be transferred into macroscopic fiber assemblies. One approach to improve the mechanical strength of the CNT assemblies is by creating covalent bonding among their individual CNT building blocks. Chemical cross-linking of multiwall CNTs (MWCNTs) within the fiber has significantly improved the strength of MWCNT thread. Results reported in this work show that the cross-linked thread had a tensile strength six times greater than the strength of its control counterpart, a pristine MWCNT thread (1192 MPa and 194 MPa, respectively). Additionally, electrical conductivity changes were observed, revealing 2123.40 S·cm-1 for cross-linked thread, and 3984.26 S·cm-1 for pristine CNT thread. Characterization suggests that the obtained high tensile strength is due to the cross-linking reaction of amine groups from ethylenediamine plasma-functionalized CNT with the epoxy groups of the cross-linking agent, 4,4-methylenebis(N,N-diglycidylaniline).

13.
Plant Cell Physiol ; 55(1): 99-118, 2014 Jan.
Article de Anglais | MEDLINE | ID: mdl-24272249

RÉSUMÉ

It is well established that 14-3-3 proteins are key regulators of multiple stress signal transduction cascades. However, the biological functions of soybean 14-3-3 proteins, especially in plant drought response, are not yet known. In this study, we characterized a Glycine soja 14-3-3 gene, GsGF14o, which is involved in plant development and drought response. GsGF14o expression was greatly induced by drought stress, as evidenced by the quantitative real-time PCR and ß-glucuronidase (GUS) activity analysis. GsGF14o overexpression in Arabidopsis thaliana resulted in decreased drought tolerance during seed germination and seedling growth. Furthermore, silencing of AtGF14µ, the most homologous 14-3-3 gene of GsGF14o, led to enhanced drought tolerance at both the seed germination and seedling stage. Unexpectedly, GsGF14o transgenic lines showed reduced water loss and transpiration rates compared with wild-type plants, which was demonstrated to be the consequence of the decreased stomatal size. At the same time, the smaller stomata due to GsGF14o overexpression led to a relatively slow net photosynthesis rate, which led to a growth penalty under drought stress. We further demonstrated that GsGF14o overexpression caused deficits in root hair formation and development, and thereby reduced the water intake capacity of the transgenic root system. In addition, GsGF14o overexpression down-regulated the transcript levels of drought-responsive marker genes. Finally, we also investigated the tissue-specific accumulation of GsGF14o by using a GUS activity assay. Collectively, the results presented here confirm that GsGF14o plays a dual role in drought stress responses through its involvement in the regulation of stomatal size and root hair development.


Sujet(s)
Protéines 14-3-3/métabolisme , Arabidopsis/physiologie , Sécheresses , Glycine max/physiologie , Racines de plante/croissance et développement , Stomates de plante/croissance et développement , Protéines de soja/métabolisme , Protéines 14-3-3/composition chimique , Adaptation physiologique/génétique , Séquence d'acides aminés , Arabidopsis/effets des médicaments et des substances chimiques , Arabidopsis/génétique , Régulation de l'expression des gènes végétaux , Techniques de knock-out de gènes , Gènes de plante , Germination/effets des médicaments et des substances chimiques , Données de séquences moléculaires , Pression osmotique , Photosynthèse , Racines de plante/génétique , Stomates de plante/anatomie et histologie , Stomates de plante/génétique , Végétaux génétiquement modifiés , ARN messager/génétique , ARN messager/métabolisme , Graines/effets des médicaments et des substances chimiques , Graines/croissance et développement , Analyse de séquence de protéine , Protéines de soja/composition chimique , Glycine max/génétique , Stress physiologique/génétique
14.
J Plant Physiol ; 170(5): 505-15, 2013 Mar 15.
Article de Anglais | MEDLINE | ID: mdl-23276523

RÉSUMÉ

Receptor-like protein kinases (RLKs) play vital roles in sensing outside signals, yet little is known about RLKs functions and roles in stress signal perception and transduction in plants, especially in wild soybean. Through the microarray analysis, GsSRK was identified as an alkaline (NaHCO3)-responsive gene, and was subsequently isolated from Glycine soja by homologous cloning. GsSRK encodes a 93.22kDa protein with a highly conserved serine/threonine protein kinase catalytic domain, a G-type lectin region, and an S-locus region. Real-time PCR results showed that the expression levels of GsSRK were largely induced by ABA, salt, and drought stresses. Over expression of GsSRK in Arabidopsis promoted seed germination, as well as primary root and rosette leaf growth during the early stages of salt stress. Compared to the wild type Arabidopsis, GsSRK overexpressors exhibited enhanced salt tolerance and higher yields under salt stress, with higher chlorophyll content, lower ion leakage, higher plant height, and more siliques at the adult developmental stage. Our studies suggest that GsSRK plays a crucial role in plant response to salt stress.


Sujet(s)
Adaptation physiologique/effets des médicaments et des substances chimiques , Glycine max/enzymologie , Lectines/métabolisme , Protein-Serine-Threonine Kinases/métabolisme , Chlorure de sodium/pharmacologie , Stress physiologique/effets des médicaments et des substances chimiques , Acide abscissique/pharmacologie , Adaptation physiologique/génétique , Séquence d'acides aminés , Arabidopsis/effets des médicaments et des substances chimiques , Arabidopsis/génétique , Sécheresses , Régulation de l'expression des gènes végétaux/effets des médicaments et des substances chimiques , Germination/effets des médicaments et des substances chimiques , Germination/génétique , Données de séquences moléculaires , Protéines végétales/composition chimique , Protéines végétales/génétique , Protéines végétales/métabolisme , Végétaux génétiquement modifiés , Protein-Serine-Threonine Kinases/génétique , ARN messager/génétique , ARN messager/métabolisme , Salinité , Graines/effets des médicaments et des substances chimiques , Graines/génétique , Graines/croissance et développement , Analyse de séquence de protéine , Glycine max/effets des médicaments et des substances chimiques , Glycine max/génétique , Glycine max/croissance et développement , Stress physiologique/génétique , Facteurs temps
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