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1.
J Am Chem Soc ; 146(13): 8939-8948, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38526452

RESUMO

Propane dehydrogenation (PDH) reaction has emerged as one of the most promising propylene production routes due to its high selectivity for propylene and good economic benefits. However, the commercial PDH processes usually rely on expensive platinum-based and poisonous chromium oxide based catalysts. The exploration of cost-effective and ecofriendly PDH catalysts with excellent catalytic activity, propylene selectivity, and stability is of great significance yet remains challenging. Here, we discovered a new active center, i.e., an unsaturated tricoordinated cobalt unit (≡Si-O)CoO(O-Mo) in a molybdenum-doped silicalite-1 zeolite, which afforded an unprecedentedly high propylene formation rate of 22.6 molC3H6 gCo-1 h-1 and apparent rate coefficient of 130 molC3H6 gCo-1 h-1 bar-1 with >99% of propylene selectivity at 550 °C. Such activity is nearly one magnitude higher than that of previously reported Co-based catalysts in which cobalt atoms are commonly tetracoordinated, and even superior to that of most of Pt-based catalysts under similar operating conditions. Density functional theory calculations combined with the state-of-the-art characterizations unravel the role of the unsaturated tricoordinated Co unit in facilitating the C-H bond-breaking of propane and propylene desorption. The present work opens new opportunities for future large-scale industrial PDH production based on inexpensive non-noble metal catalysts.

2.
Inorg Chem ; 63(17): 7937-7945, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38629190

RESUMO

The urea-assisted water splitting not only enables a reduction in energy consumption during hydrogen production but also addresses the issue of environmental pollution caused by urea. Doping heterogeneous atoms in Ni-based electrocatalysts is considered an efficient means for regulating the electronic structure of Ni sites in catalytic processes. However, the current methodologies for synthesizing heteroatom-doped Ni-based electrocatalysts exhibit certain limitations, including intricate experimental procedures, prolonged reaction durations, and low product yield. Herein, Fe-doped NiO electrocatalysts were successfully synthesized using a rapid and facile solution combustion method, enabling the synthesis of 1.1107 g within a mere 5 min. The incorporation of iron atoms facilitates the modulation of the electronic environment around Ni atoms, generating a substantial decrease in the Gibbs free energy of intermediate species for the Fe-NiO catalyst. This modification promotes efficient cleavage of C-N bonds and consequently enhances the catalytic performance of UOR. Benefiting from the tunability of the electronic environment around the active sites and its efficient electron transfer, Fe-NiO electrocatalysts only needs 1.334 V to achieve 50 mA cm-2 during UOR. Moreover, Fe-NiO catalysts were integrated into a dual electrode urea electrolytic system, requiring only 1.43 V of cell voltage at 10 mA cm-2.

3.
Angew Chem Int Ed Engl ; 63(15): e202319996, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38316641

RESUMO

Metal halide perovskites (MHPs), renowned for their outstanding optoelectronic properties, hold significant promise as photocatalysts for hydrogen evolution reaction (HER). However, the low stability and insufficient exposure of catalytically active sites of bulky MHPs seriously impair their catalytic efficiency. Herein, we utilized an extra-large-pore zeolite ZEO-1 (JZO) as a host to confine and stabilize the CsPbBr3 nanocrystals (3.4 nm) for boosting hydrogen iodide (HI) splitting. The as-prepared CsPbBr3@ZEO-1 featured sufficiently exposed active sites, superior stability in acidic media, along with intrinsic extra-large pores of ZEO-1 that were favorable for molecule/ion adsorption and diffusion. Most importantly, the unique nanoconfinement effect of ZEO-1 led to the narrowing of the band gap of CsPbBr3, allowing for more efficient light utilization. As a result, the photocatalytic HER rate of the as-prepared CsPbBr3@ZEO-1 photocatalyst was increased to 1734 µmol ⋅ h-1 ⋅ g-1 (CsPbBr3) under visible light irradiation compared with bulk CsPbBr3 (11 µmol ⋅ h-1 ⋅ g-1 (CsPbBr3)), and the long-term durability (36 h) can be achieved. Furthermore, Pt was incorporated with well-dispersed CsPbBr3 nanocrystals into ZEO-1, resulting in a significant enhancement in activity (4826 µmol ⋅ h-1 ⋅ g-1 (CsPbBr3)), surpassing most of the Pt-integrated perovskite-based photocatalysts. Density functional theory (DFT) calculations and charge-carrier dynamics investigation revealed that the dramatically boosted photocatalytic performance of Pt/CsPbBr3@ZEO-1 could be attributed to the promotion of charge separation and transfer, as well as to the substantially lowered energy barrier for HER. This work highlights the advantage of extra-large-pore zeolites as the nanoscale platform to accommodate multiple photoactive components, opening up promising prospects in the design and exploitation of novel zeolite-confined photocatalysts for energy harvesting and storage.

4.
J Am Chem Soc ; 145(39): 21231-21241, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37748094

RESUMO

Zeolite nonclassical growth via particle attachment has been proposed for two decades, yet the attachment mechanism and kinetic regulation remain elusive. Here, nonclassical growth of an MFI-type zeolite has been achieved by using amorphous protozeolite (PZ) nanoparticles containing encapsulated TPA+ templates and abundant silanols (Si-OH) as sole precursors under hydrothermal conditions. The silanol characteristics of the precursor were studied by two-dimensional (2D) solid-state nuclear magnetic resonance (NMR) correlation spectroscopy, which were proven to play critical roles in determining precursor attachment behavior and crystal growth orientation. Under mechanical ball-milling or tablet-pressing process, pressure drove the fusion of spherical PZ into platelet-like integrated PZ (IPZ) coupled with transformations of external silanols from evenly distributed to curvature-dependent distributed and internal silanols from isolated to spatially proximate. Compared to isolated silanols, the spatially proximate silanols possessed a stronger correlation with TPA+, benefiting the formation of Si-O-Si bonds via silanol condensation. Subsequently, driven by minimization of surface energy, particle attachment of the platelet-like IPZ precursor preferentially occurred at high-curvature surfaces with high-density silanols, leading to anisotropic rates of nonclassical growth and thus the formation of high-aspect-ratio MFI-type zeolite nanosheets. Advanced electron microscopy provided direct evidence of attachment of amorphous IPZ precursors to crystalline intermediate surfaces along the c-axis direction with the formation of amorphous-crystalline interfaces, followed by interface elimination and structural evolution to a single-crystalline phase. Our findings not only unravel the zeolite nonclassical growth mechanism but also reveal the critical role of silanol chemistry in kinetic regulation, which is of great importance for pursuing a tailored zeolite synthesis.

5.
Plant Physiol ; 190(1): 421-440, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-35695786

RESUMO

Adapting to unfavorable environments is a necessary step in plant terrestrialization and radiation. The dehydration-responsive element-binding (DREB) protein subfamily plays a pivotal role in plant abiotic stress regulation. However, relationships between the origin and expansion of the DREB subfamily and adaptive evolution of land plants are still being elucidated. Here, we constructed the evolutionary history of the DREB subfamily by compiling APETALA2/ethylene-responsive element-binding protein superfamily genes from 169 representative species of green plants. Through extensive phylogenetic analyses and comparative genomic analysis, our results revealed that the DREB subfamily diverged from the ethylene-responsive factor (ERF) subfamily in the common ancestor of Zygnemophyceae and Embryophyta during the colonization of land by plants, followed by expansions to form three different ancient archetypal genes in Zygnemophyceae species, designated as groups archetype-I, archetype-II/III, and archetype-IV. Four large-scale expansions paralleling the evolution of land plants led to the nine-subgroup divergence of group archetype-II/III in angiosperms, and five whole-genome duplications during Brassicaceae and Poaceae radiation shaped the diversity of subgroup IIb-1. We identified a Poaceae-specific gene in subgroup IIb-1, ERF014, remaining in a Poaceae-specific microsynteny block and co-evolving with a small heat shock protein cluster. Expression analyses demonstrated that heat acclimation may have driven the neofunctionalization of ERF014s in Pooideae by engaging in the conserved heat-responsive module in Poaceae. This study provides insights into lineage-specific expansion and neofunctionalization in the DREB subfamily, together with evolutionary information valuable for future functional studies of plant stress biology.


Assuntos
Proteínas de Transporte , Desidratação , Proteínas de Transporte/metabolismo , Desidratação/genética , Etilenos , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poaceae/genética
6.
BMC Med Imaging ; 23(1): 82, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37312026

RESUMO

BACKGROUND: In clinical practice, reducing unnecessary biopsies for mammographic BI-RADS 4 lesions is crucial. The objective of this study was to explore the potential value of deep transfer learning (DTL) based on the different fine-tuning strategies for Inception V3 to reduce the number of unnecessary biopsies that residents need to perform for mammographic BI-RADS 4 lesions. METHODS: A total of 1980 patients with breast lesions were included, including 1473 benign lesions (185 women with bilateral breast lesions), and 692 malignant lesions collected and confirmed by clinical pathology or biopsy. The breast mammography images were randomly divided into three subsets, a training set, testing set, and validation set 1, at a ratio of 8:1:1. We constructed a DTL model for the classification of breast lesions based on Inception V3 and attempted to improve its performance with 11 fine-tuning strategies. The mammography images from 362 patients with pathologically confirmed BI-RADS 4 breast lesions were employed as validation set 2. Two images from each lesion were tested, and trials were categorized as correct if the judgement (≥ 1 image) was correct. We used precision (Pr), recall rate (Rc), F1 score (F1), and the area under the receiver operating characteristic curve (AUROC) as the performance metrics of the DTL model with validation set 2. RESULTS: The S5 model achieved the best fit for the data. The Pr, Rc, F1 and AUROC of S5 were 0.90, 0.90, 0.90, and 0.86, respectively, for Category 4. The proportions of lesions downgraded by S5 were 90.73%, 84.76%, and 80.19% for categories 4 A, 4B, and 4 C, respectively. The overall proportion of BI-RADS 4 lesions downgraded by S5 was 85.91%. There was no significant difference between the classification results of the S5 model and pathological diagnosis (P = 0.110). CONCLUSION: The S5 model we proposed here can be used as an effective approach for reducing the number of unnecessary biopsies that residents need to conduct for mammographic BI-RADS 4 lesions and may have other important clinical uses.


Assuntos
Neoplasias da Mama , Mamografia , Humanos , Feminino , Mama/diagnóstico por imagem , Biópsia , Aprendizado de Máquina , Neoplasias da Mama/diagnóstico por imagem
7.
Angew Chem Int Ed Engl ; 62(48): e202313101, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37792288

RESUMO

The selective hydrogenation of alkynes to alkenes is a crucial step in the synthesis of fine chemicals. However, the widely utilized palladium (Pd)-based catalysts often suffer from poor selectivity. In this work, we demonstrate a carbonization-reduction method to create palladium carbide subnanometric species within pure silicate MFI zeolite. The carbon species can modify the electronic and steric characteristics of Pd species by forming the predominant Pd-C4 structure and, meanwhile, facilitate the desorption of alkenes by forming the Si-O-C structure with zeolite framework, as validated by the state-of-the-art characterizations and theoretical calculations. The developed catalyst shows superior performance in the selective hydrogenation of alkynes over mild conditions (298 K, 2 bar H2 ), with 99 % selectivity to styrene at a complete conversion of phenylacetylene. In contrast, the zeolite-encapsulated carbon-free Pd catalyst and the commercial Lindlar catalyst show only 15 % and 14 % selectivity to styrene, respectively, under identical reaction conditions. The zeolite-confined Pd-carbide subnanoclusters promise their superior properties in semihydrogenation of alkynes.

8.
Future Oncol ; 18(39): 4361-4370, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36519579

RESUMO

Aim: To explore the ability of You Only Look Once version 5 (YOLOv5) to detect and classify breast lesions on dynamic contrast-enhanced MRI. Methods: Four YOLOv5 submodels were examined. A total of 2124 and 2226 images of benign and malignant lesions were obtained, respectively. Precision, recall rate and mean average precision were used to evaluate model performance. Results: The precision (0.916) and mean average precision _0.5 (0.894) of YOLOv5s were higher than those of YOLOv5m (0.832, 0.794), YOLOv5l (0.843, 0.803) and YOLOv5x (0.854, 0.821). In the validation set, YOLOv5s required 1.1 ms to detect lesions per image. Conclusion: YOLOv5s was the fastest and had the highest precision among the four YOLOv5 submodels for the detection and classification of breast lesions on dynamic contrast-enhanced MRI. It has a greater clinical application value.


You Only Look Once version 5 (YOLOv5) is the latest YOLO series, which may be a useful tool for detecting and classifying breast lesions on dynamic contrast-enhanced MRI (DCE-MRI) and help clinicians make a rapid, accurate diagnosis and provide treatment. Data were retrospectively collected from a single-center study. The performances of the four submodels (YOLOv5s, YOLOv5m, YOLOv5l and YOLOv5x) were compared. The diagnostic performances of YOLOv5s were comparable with some convolutional neural network models for breast lesion identification in breast ultrasonography and mammography. This study may provide novel insights into the detection and classification of breast lesions on DCE-MRI. Thus, a sufficiently large series of data and high-quality DCE-MRIs are warranted. Owing to its applications in artificial intelligence-assisted imaging diagnosis, this method has promising prospects.


Assuntos
Neoplasias da Mama , Imageamento por Ressonância Magnética , Humanos , Feminino , Imageamento por Ressonância Magnética/métodos , Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste
9.
Int J Mol Sci ; 23(4)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35216210

RESUMO

The SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL) gene family affects plant architecture, panicle structure, and grain development, representing key genes for crop improvements. The objective of the present study is to utilize the well characterized SPLs' functions in rice to facilitate the functional genomics of TaSPL genes. To achieve these goals, we combined several approaches, including genome-wide analysis of TaSPLs, comparative genomic analysis, expression profiling, and functional study of TaSPL3 in rice. We established the orthologous relationships of 56 TaSPL genes with the corresponding OsSPLs, laying a foundation for the comparison of known SPL functions between wheat and rice. Some TaSPLs exhibited different spatial-temporal expression patterns when compared to their rice orthologs, thus implicating functional divergence. TaSPL2/6/8/10 were identified to respond to different abiotic stresses through the combination of RNA-seq and qPCR expression analysis. Additionally, ectopic expression of TaSPL3 in rice promotes heading dates, affects leaf and stem development, and leads to smaller panicles and decreased yields per panicle. In conclusion, our work provides useful information toward cataloging of the functions of TaSPLs, emphasized the conservation and divergence between TaSPLs and OsSPLs, and identified the important SPL genes for wheat improvement.


Assuntos
Genoma de Planta/genética , Oryza/genética , Proteínas de Plantas/genética , Triticum/genética , Grão Comestível/genética , Regulação da Expressão Gênica de Plantas/genética , Plantas Geneticamente Modificadas/genética
10.
Plant Biotechnol J ; 19(8): 1588-1601, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33638922

RESUMO

Cultivating new crop cultivars with multiple abiotic stress tolerances is important for crop production. The abscisic acid-stress-ripening (ASR) protein has been shown to confer abiotic stress tolerance in plants. However, the mechanisms of ASR function under stress condition remain largely unclear. In this study, we characterized all ASR family members in common wheat and constitutively overexpressed TaASR1-D in a commercial hexaploid wheat cultivar Zhengmai 9023. The transgenic wheat plants exhibited increased tolerance to multiple abiotic stresses and increased grain yields under salt stress condition. Overexpression of TaASR1-D conferred enhanced antioxidant capacity and ABA sensitivity in transgenic wheat plants. Further, RNA in situ hybridization results showed that TaASR1-D had higher expression levels in the vascular tissues of leaves and the parenchyma cells around the vascular tissues of roots and stems. Yeast one-hybrid and electrophoretic mobility shift assays revealed that TaASR1-D could directly bind the specific cis-elements in the promoters of TaNCED1 and TaGPx1-D. In conclusion, our findings suggest that TaASR1-D can be used to breed new wheat cultivars with increased multiple abiotic stress tolerances, and TaASR1-D enhances abiotic stress tolerances by reinforcing antioxidant capacity and ABA signalling.


Assuntos
Regulação da Expressão Gênica de Plantas , Triticum , Ácido Abscísico , Secas , Regulação da Expressão Gênica de Plantas/genética , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética , Triticum/genética , Triticum/metabolismo
11.
Plant Cell Rep ; 39(5): 635-651, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32065246

RESUMO

KEY MESSAGE: A wheat protein phosphatase PP2C-a10, which interacted with TaDOG1L1 and TaDOG1L4, promoted seed germination and decreased drought tolerance of transgenic Arabidopsis. Seed dormancy and germination are critical to plant fitness. DELAY OF GERMINATION 1 (DOG1) is a quantitative trait locus for dormancy in Arabidopsis thaliana. Some interactions between DOG1 and the type 2C protein phosphatases (PP2Cs) have been reported in Arabidopsis. However, the research on molecular functions and regulations of DOG1Ls and group A PP2Cs in wheat (Triticum aestivum. L), an important crop plant, is rare. In this study, the whole TaDOG1L family was identified. Expression analysis revealed that TaDOG1L2, TaDOG1L4 and TaDOG1L-N2 specially expressed in wheat grains, while others displayed distinct expression patterns. Yeast two-hybrid analysis of TaDOG1Ls and group A TaPP2Cs revealed interaction patterns differed from those in Arabidopsis, and TaDOG1L1 and TaDOG1L4 interacted with TaPP2C-a10. The qRT-PCR analysis showed that TaPP2C-a10 exhibited the highest transcript level in wheat grains. Further investigation showed that ectopic expression of TaPP2C-a10 in Arabidopsis promoted seed germination and decreased sensitivity to ABA during germination stage. Additionally, TaPP2C-a10 transgenic Arabidopsis exhibited decreased tolerance to drought stress. Finally, the phylogenetic analysis indicated that TaPP2C-a10 gene was conserved in angiosperm during evolutionary process. Overall, our results reveal the role of TaPP2C-a10 in seed germination and abiotic stress response, as well as the functional diversity of TaDOG1L family.


Assuntos
Arabidopsis/metabolismo , Germinação/genética , Dormência de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteína Fosfatase 2C/metabolismo , Estresse Fisiológico/genética , Triticum/enzimologia , Ácido Abscísico/metabolismo , Arabidopsis/genética , Arabidopsis/fisiologia , Secas , Regulação da Expressão Gênica de Plantas/genética , Germinação/fisiologia , Filogenia , Dormência de Plantas/fisiologia , Proteína Fosfatase 2C/genética , Sementes/genética , Sementes/metabolismo , Triticum/genética , Técnicas do Sistema de Duplo-Híbrido
12.
Int J Mol Sci ; 21(4)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32075191

RESUMO

Kernel hardness is a key trait of wheat seeds, largely controlled by two tightly linked genes Puroindoline a and b (Pina and Pinb). Genes homologous to Pinb, namely Pinb2, have been studied. Whether these genes contribute to kernel hardness and other important seed traits remains inconclusive. Using the high-quality bread wheat reference genome, we show that PINB2 are encoded by three homoeologous loci Pinb2 not syntenic to the Hardness locus, with Pinb2-7A locus containing three tandem copies. PINB2 proteins have several features conserved for the Pin/Pinb2 phylogenetic cluster but lack a structural basis of significant impact on kernel hardness. Pinb2 are seed-specifically expressed with varied expression levels between the homoeologous copies and among wheat varieties. Using the high-quality genome information, we developed new Pinb2 allele specific markers and demonstrated their usefulness by 1) identifying new Pinb2 alleles in Triticeae species; and 2) performing an association analysis of Pinb2 with kernel hardness. The association result suggests that Pinb2 genes may have no substantial contribution to kernel hardness. Our results provide new insights into Pinb2 evolution and expression and the new allele-specific markers are useful to further explore Pinb2's contribution to seed traits in wheat.


Assuntos
Genoma de Planta , Proteínas de Plantas/genética , Triticum/genética , Alelos , Sequência de Aminoácidos , Estudos de Associação Genética , Loci Gênicos , Genômica/métodos , Genótipo , Filogenia , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Poaceae/genética , Sementes/fisiologia , Alinhamento de Sequência
13.
Int J Mol Sci ; 21(3)2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32033029

RESUMO

The present research reported the effects of structural properties and immunoreactivity of celiac-toxic peptides and wheat storage proteins modified by cold jet atmospheric pressure (CJAP) plasma. It could generate numerous high-energy excited atoms, photons, electrons, and reactive oxygen and nitrogen species, including O3, H2O2, •OH, NO2- and NO3- etc., to modify two model peptides and wheat storage proteins. The Orbitrap HR-LC-MS/MS was utilized to identify and quantify CJAP plasma-modified model peptide products. Backbone cleavage of QQPFP and PQPQLPY at specific proline and glutamine residues, accompanied by hydroxylation at the aromatic ring of phenylalanine and tyrosine residues, contributed to the reduction and modification of celiac-toxic peptides. Apart from fragmentation, oxidation, and agglomeration states were evaluated, including carbonyl formation and the decline of γ-gliadin. The immunoreactivity of gliadin extract declined over time, demonstrating a significant decrease by 51.95% after 60 min of CJAP plasma treatment in vitro. The CJAP plasma could initiate depolymerization of gluten polymer, thereby reducing the amounts of large-sized polymers. In conclusion, CJAP plasma could be employed as a potential technique in the modification and reduction of celiac-toxic peptides and wheat storage proteins.


Assuntos
Gliadina/imunologia , Glutens/química , Proteínas de Plantas/imunologia , Gases em Plasma/química , Triticum/química , Pressão Atmosférica , Doença Celíaca/imunologia , Doença Celíaca/patologia , Humanos , Peróxido de Hidrogênio/química , Hidroxilação , Oxirredução , Proteínas de Plantas/química , Espécies Reativas de Nitrogênio/química
14.
BMC Genomics ; 20(1): 986, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842737

RESUMO

BACKGROUND: Glutathione transferases (GSTs), the ancient, ubiquitous and multi-functional proteins, play significant roles in development, metabolism as well as abiotic and biotic stress responses in plants. Wheat is one of the most important crops, but the functions of GST genes in wheat were less studied. RESULTS: A total of 330 TaGST genes were identified from the wheat genome and named according to the nomenclature of rice and Arabidopsis GST genes. They were classified into eight classes based on the phylogenetic relationship among wheat, rice, and Arabidopsis, and their gene structure and conserved motif were similar in the same phylogenetic class. The 43 and 171 gene pairs were identified as tandem and segmental duplication genes respectively, and the Ka/Ks ratios of tandem and segmental duplication TaGST genes were less than 1 except segmental duplication gene pair TaGSTU24/TaGSTU154. The 59 TaGST genes were identified to have syntenic relationships with 28 OsGST genes. The expression profiling involved in 15 tissues and biotic and abiotic stresses suggested the different expression and response patterns of the TaGST genes. Furthermore, the qRT-PCR data showed that GST could response to abiotic stresses and hormones extensively in wheat. CONCLUSIONS: In this study, a large GST family with 330 members was identified from the wheat genome. Duplication events containing tandem and segmental duplication contributed to the expansion of TaGST family, and duplication genes might undergo extensive purifying selection. The expression profiling and cis-elements in promoter region of 330 TaGST genes implied their roles in growth and development as well as adaption to stressful environments. The qRT-PCR data of 14 TaGST genes revealed that they could respond to different abiotic stresses and hormones, especially salt stress and abscisic acid. In conclusion, this study contributed to the further functional analysis of GST genes family in wheat.


Assuntos
Perfilação da Expressão Gênica/métodos , Glutationa Transferase/genética , Hormônios/farmacologia , Triticum/crescimento & desenvolvimento , Evolução Molecular , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genoma de Planta , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Estresse Fisiológico , Triticum/efeitos dos fármacos , Triticum/enzimologia
15.
BMC Genomics ; 20(1): 287, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975075

RESUMO

BACKGROUND: The trihelix gene family is a plant-specific transcription factor family that plays important roles in plant growth, development, and responses to abiotic stresses. However, to date, no systemic characterization of the trihelix genes has yet been conducted in wheat and its close relatives. RESULTS: We identified a total of 94 trihelix genes in wheat, as well as 22 trihelix genes in Triticum urartu, 29 in Aegilops tauschii, and 31 in Brachypodium distachyon. We analyzed the chromosomal locations and orthology relations of the identified trihelix genes, and no trihelix gene was found to be located on chromosome 7A, 7B, or 7D of wheat, thereby reflecting the uneven distributions of wheat trihelix genes. Phylogenetic analysis indicated that the 186 identified trihelix proteins in wheat, rice, B. distachyon, and Arabidopsis were clustered into five major clades. The trihelix genes belonging to the same clades usually shared similar motif compositions and exon/intron structural patterns. Five pairs of tandem duplication genes and three pairs of segmental duplication genes were identified in the wheat trihelix gene family, thereby validating the supposition that more intrachromosomal gene duplication events occur in the genome of wheat than in that of other grass species. The tissue-specific expression and differential expression profiling of the identified genes under cold and drought stresses were analyzed by using RNA-seq data. qRT-PCR was also used to confirm the expression profiles of ten selected wheat trihelix genes under multiple abiotic stresses, and we found that these genes mainly responded to salt and cold stresses. CONCLUSIONS: In this study, we identified trihelix genes in wheat and its close relatives and found that gene duplication events are the main driving force for trihelix gene evolution in wheat. Our expression profiling analysis demonstrated that wheat trihelix genes responded to multiple abiotic stresses, especially salt and cold stresses. The results of our study built a basis for further investigation of the functions of wheat trihelix genes and provided candidate genes for stress-resistant wheat breeding programs.


Assuntos
Perfilação da Expressão Gênica , Genômica , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Triticum/genética , Triticum/fisiologia , Cromossomos de Plantas/genética , Especificidade de Órgãos , Filogenia , Homologia de Sequência do Ácido Nucleico , Sintenia
16.
BMC Plant Biol ; 19(1): 126, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30947699

RESUMO

BACKGROUND: Durum wheat is considered not suitable for making many food products that bread wheat can. This limitation is largely due to: (i) lack of grain-hardness controlling genes (Puroindoline a and b) and consequently extremely-hard kernel; (ii) lack of high- and low-molecular-weight glutenin subunit loci (Glu-D1 and Glu-D3) that contribute to gluten strength. To improve food processing quality of durum wheat, we stacked transgenic Pina and HMW-glutenin subunit 1Ax1 in durum wheat and developed lines with medium-hard kernel texture. RESULTS: Here, we demonstrated that co-expression of Pina + 1Ax1 in durum wheat did not affect the milling performance that was enhanced by Pina expression. While stacking of Pina + 1Ax1 led to increased flour yield, finer flour particles and decreased starch damage compared to the control lines. Interestingly, Pina and 1Ax1 co-expression showed synergistic effects on the pasting attribute peak viscosity. Moreover, Pina and 1Ax1 co-expression suggests that PINA impacts gluten aggregation via interaction with gluten protein matrix. CONCLUSIONS: The results herein may fill the gap of grain hardness between extremely-hard durum wheat and the soft kernel durum wheat, the latter of which has been developed recently. Our results may also serve as a proof of concept that stacking Puroindolines and other genes contributing to wheat end-use quality from the A and/or D genomes could improve the above-mentioned bottleneck traits of durum wheat and help to expand its culinary uses.


Assuntos
Glutens/genética , Triticum/genética , Pão , Grão Comestível/genética , Grão Comestível/fisiologia , Dureza , Fenótipo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Triticum/fisiologia
17.
BMC Genomics ; 19(1): 803, 2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30400808

RESUMO

BACKGROUND: WD40 domains are abundant in eukaryotes, and they are essential subunits of large multiprotein complexes, which serve as scaffolds. WD40 proteins participate in various cellular processes, such as histone modification, transcription regulation, and signal transduction. WD40 proteins are regarded as crucial regulators of plant development processes. However, the systematic identification and analysis of WD40 proteins have yet to be reported in wheat. RESULTS: In this study, a total of 743 WD40 proteins were identified in wheat, and they were grouped into 5 clusters and 11 subfamilies. Their gene structures, chromosomal locations, and evolutionary relationships were analyzed. Among them, 39 and 46 pairs of TaWD40s were distinguished as tandem duplication and segmental duplication genes. The 123 OsWD40s were identified to exhibit synteny with TaWD40s. TaWD40s showed the specific characteristics at the reproductive developmental stage, and numerous TaWD40s were involved in responses to stresses, including cold, heat, drought, and powdery mildew infection pathogen, based on the result of RNA-seq data analysis. The expression profiles of some TaWD40s in wheat seed development were confirmed through qRT-PCR technique. CONCLUSION: In this study, 743 TaWD40s were identified from the wheat genome. As the main driving force of evolution, duplication events were observed, and homologous recombination was another driving force of evolution. The expression profiles of TaWD40s revealed their importance for the growth and development of wheat and their response to biotic and abiotic stresses. Our study also provided important information for further functional characterization of some WD40 proteins in wheat.


Assuntos
Evolução Molecular , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Família Multigênica , Proteínas de Plantas/genética , Triticum/genética , Repetições WD40 , Biologia Computacional , Secas , Perfilação da Expressão Gênica , Filogenia , Regiões Promotoras Genéticas , Estresse Fisiológico , Triticum/crescimento & desenvolvimento
18.
BMC Genomics ; 19(1): 852, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30497365

RESUMO

Following the publication of this article [1], the authors reported the following errors.

19.
Planta ; 248(1): 117-137, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29616395

RESUMO

MAIN CONCLUSION: TaGF14b enhances tolerance to multiple stresses through ABA signaling pathway by altering physiological and biochemical processes, including ROS-scavenging system, stomatal closure, compatible osmolytes, and stress-related gene expressions in tobaccos. The 14-3-3 proteins are involved in plant growth, development, and in responding to abiotic stresses. However, the precise functions of 14-3-3s in responding to drought and salt stresses remained unclear, especially in wheat. In this study, a 14-3-3 gene from wheat, designated TaGF14b, was cloned and characterized. TaGF14b was upregulated by polyethylene glycol 6000, sodium chloride, hydrogen peroxide, and abscisic acid (ABA) treatments. Ectopic expression of TaGF14b in tobacco conferred enhanced tolerance to drought and salt stresses. Transgenic tobaccos had longer root, better growth status, and higher relative water content, survival rate, photosynthetic rate, and water use efficiency than control plants under drought and salt stresses. The contribution of TaGF14b to drought and salt tolerance relies on the regulations of ABA biosynthesis and ABA signaling, as well as stomatal closure and stress-related gene expressions. Moreover, TaGF14b expression could significantly enhance the reactive oxygen species (ROS) scavenging system to ameliorate oxidative damage to cells. In addition, TaGF14b increased tolerance to osmotic stress evoked by drought and salinity through modifying water conservation and compatible osmolytes in plants. In conclusion, TaGF14b enhances tolerance to multiple abiotic stresses through the ABA signaling pathway in transgenic tobaccos by altering physiological and biochemical processes.


Assuntos
Proteínas 14-3-3/genética , Triticum/genética , Proteínas 14-3-3/fisiologia , Desidratação , Genes de Plantas/genética , Filogenia , Plantas Geneticamente Modificadas/genética , Tolerância ao Sal , Plantas Tolerantes a Sal/genética , Alinhamento de Sequência , Transdução de Sinais , Nicotiana/genética , Nicotiana/fisiologia , Triticum/fisiologia
20.
Acta Biochim Biophys Sin (Shanghai) ; 50(2): 199-208, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29309501

RESUMO

Calcineurin B-like protein (CBL), the Ca2+ sensor, and its interacting protein kinases (CIPKs) play essential roles in plants' response to stress. However, few studies have focused on the functions of CIPKs in low-temperature response. In the present study, BdCIPK31, a cold-responsive CIPK in Brachypodium distachyon, was found to participate in low-temperature response. Ectopic expression of BdCIPK31 conferred cold tolerance in transgenic tobaccos. Further analyses indicated that expression of BdCIPK31 improved ROS detoxication and omsoprotectant biosynthesis in transgenic plants under low-temperature treatment, suggesting that the BdCIPK31 functions positively in plant adaption to the cold-induced oxidative and osmotic stresses. Moreover, BdCIPK31 could upregulate the expressions of some representative stress-related genes under cold stress. In conclusion, these findings suggest that BdCIPK31 functions positively in plant cold response.


Assuntos
Adaptação Fisiológica/genética , Brachypodium/genética , Temperatura Baixa , Expressão Ectópica do Gene , Nicotiana/genética , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Nicotiana/metabolismo
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