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1.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675002

RESUMO

Fasciclin-like arabinogalactan proteins (FLAs) are a subclass of arabinogalactan proteins (AGPs) containing both AGP-like glycated domains and fasciclin (FAS) domains, which are involved in plant growth and development and synthesis of the cell wall. However, these proteins have not been identified or analyzed in willow, Salix, the sister genus of Populus. In this study, we performed a whole genome study of the FLA gene family of Salix suchowensis and compared it with the FLA gene family of Populus deltoides. The results showed the presence of 40 and 46 FLA genes in P. deltoides and S. suchowensis, distributed on 17 and 16 chromosomes, respectively. Four pairs of tandem repeat genes were found in willow, while poplar had no tandem repeat genes. Twelve and thirteen pairs of duplicated gene fragments were identified in poplar and willow, respectively. The multispecies phylogenetic tree showed that the FLA gene family could be divided into four groups (I-IV), with Group 1 showing significant expansion in woody plants. A gene expression analysis showed that PdeFLA19/27 in Group I of poplar was highly expressed, specifically during the secondary growth period of the stem and the rapid elongation of seed hairs. In the Group I genes of S. suchowensis, SsuFLA25/26/28 was also highly expressed during the secondary growth period, whereas increased expression of SsuFLA35 was associated with seed hair tissue. These results provide important clues about the differences in the FLA gene family during the evolution of herbs and woody plants, and suggest that the FLA gene family may play an essential role in regulating the secondary growth of woody plants. It also provides a reference for further studies on the regulation of secondary growth and seed hair development by FLA genes in poplar and willow.


Assuntos
Proteínas de Plantas , Populus , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Crescimento e Desenvolvimento , Regulação da Expressão Gênica de Plantas , Populus/genética , Populus/metabolismo
2.
Int J Mol Sci ; 24(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37175464

RESUMO

Expansins are a group of cell wall enzyme proteins that help to loosen cell walls by breaking hydrogen bonds between cellulose microfibrils and hemicellulose. Expansins are essential plant proteins that are involved in several key processes, including seed germination, the growth of pollen tubes and root hairs, fruit ripening and abscission processes. Currently, there is a lack of knowledge concerning the role of expansins in woody plants. In this study, we analyzed expansin genes using Populus genome as the study target. Thirty-six members of the expansin gene family were identified in Populus that were divided into four subfamilies (EXPA, EXPB, EXLA and EXLB). We analyzed the molecular structure, chromosome localization, evolutionary relationships and tissue specificity of these genes and investigated expression changes in responses to phytohormone and abiotic stresses of the expansin genes of Populus tremula L. (PtEXs). Molecular structure analysis revealed that each PtEX protein had several conserved motifs and all of the PtEXs genes had multiple exons. Chromosome structure analysis showed that the expansin gene family is distributed on 14 chromosomes. The PtEXs gene family expansion patterns showed segmental duplication. Transcriptome data of Populus revealed that 36 PtEXs genes were differently expressed in different tissues. Cis-element analysis showed that the PtEXs were closely associated with plant development and responses to phytohormone and abiotic stress. Quantitative real-time PCR showed that abscisic acid (ABA) and low-temperature treatment affected the expression of some PtEXs genes, suggesting that these genes are involved in responses to phytohormone and abiotic stress. This study provides a further understanding of the expansin gene family in Populus and forms a basis for future functional research studies.


Assuntos
Reguladores de Crescimento de Plantas , Populus , Reguladores de Crescimento de Plantas/farmacologia , Ácido Abscísico/farmacologia , Populus/genética , Populus/metabolismo , Temperatura , Genoma de Planta , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia , Família Multigênica , Estresse Fisiológico/genética
3.
Nature ; 535(7610): 148-52, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27362227

RESUMO

The non-receptor protein tyrosine phosphatase SHP2, encoded by PTPN11, has an important role in signal transduction downstream of growth factor receptor signalling and was the first reported oncogenic tyrosine phosphatase. Activating mutations of SHP2 have been associated with developmental pathologies such as Noonan syndrome and are found in multiple cancer types, including leukaemia, lung and breast cancer and neuroblastoma. SHP2 is ubiquitously expressed and regulates cell survival and proliferation primarily through activation of the RAS­ERK signalling pathway. It is also a key mediator of the programmed cell death 1 (PD-1) and B- and T-lymphocyte attenuator (BTLA) immune checkpoint pathways. Reduction of SHP2 activity suppresses tumour cell growth and is a potential target of cancer therapy. Here we report the discovery of a highly potent (IC50 = 0.071 µM), selective and orally bioavailable small-molecule SHP2 inhibitor, SHP099, that stabilizes SHP2 in an auto-inhibited conformation. SHP099 concurrently binds to the interface of the N-terminal SH2, C-terminal SH2, and protein tyrosine phosphatase domains, thus inhibiting SHP2 activity through an allosteric mechanism. SHP099 suppresses RAS­ERK signalling to inhibit the proliferation of receptor-tyrosine-kinase-driven human cancer cells in vitro and is efficacious in mouse tumour xenograft models. Together, these data demonstrate that pharmacological inhibition of SHP2 is a valid therapeutic approach for the treatment of cancers.


Assuntos
Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Piperidinas/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Pirimidinas/farmacologia , Receptores Proteína Tirosina Quinases/metabolismo , Regulação Alostérica/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Concentração Inibidora 50 , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Nus , Modelos Moleculares , Neoplasias/patologia , Proteína Oncogênica p21(ras)/metabolismo , Piperidinas/química , Piperidinas/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Estabilidade Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 11/química , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Pirimidinas/química , Pirimidinas/uso terapêutico , Reprodutibilidade dos Testes , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Plant Dis ; 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35802015

RESUMO

Shanxin yang (Populus davidiana × P. bolleana) is a commercially valuable hybrid poplar that is widely planted in northern China. Efficient genetic transformation and gene-editing systems have been established for this hybrid poplar (Wang et al., 2011; Wang et al., 2020). However, records of fungal diseases on Shanxin yang are very limited. In July 2020, large necrotic lesions were observed on 16 one-year-old Shanxin yang seedlings planted in a greenhouse of Nanjing Forestry University, Nanjing, China. The disease symptoms appeared mostly on the leaves and not on the stems. Symptoms first manifested as differently sized and shaped brown spots, having clearly demarcated margins. As the disease progressed, the spots coalesced, and large lesions were present on the leaves. Severe infections resulted in whole-plant defoliation and eventually plant death. Small leaf samples (5 mm2) cut from lesion margins were surface sterilized with 75% ethanol for 30 s, followed by 1% NaClO for 90 s and then washed three times with sterile distilled water. After drying on sterilized filter paper, the cut tissues were plated on potato dextrose agar (PDA) supplemented with ampicillin (100 µg/mL) and incubated at 25°C in the dark. Three isolates (named as SX-1, SX-2 and SX-3, respectively) were obtained after 5 days. The isolation frequency was low, which might be due to the greenhouse microclimate that was unfavorable for pathogen spread. Mycelial plugs (5 mm) cut from the leading edge of the mycelia were transferred onto fresh PDA and synthetic nutrient-poor agar (SNA) plates to obtain pure cultures. On both media, colonies of the isolates were white on the front and light yellowish on the back, with concentric zonation. Abundant aerial mycelia developed; the hyphae were hyaline, non-septate, and approximately 0.794-2.961 µm in diameter. On the SNA medium, SX-1 and SX-3 produced globose to subglobose, black pycnidia after 18 days under a 12 h photoperiod. The alpha conidia were fusoid, aseptate, hyaline, smooth, and 6.4 ± 1.2 × 2.4 ± 0.6 µm (n = 50) in size. Under the same conditions, SX-2 produced pycnidia after 20 days, and the conidia were 2.8 ± 0.7 × 7.5 ± 1.3 µm. Beta conidia were not observed on any colony. Based on the morphological characteristics, the isolated mycelia resembled Diaporthe spp. (Gomes et al., 2013). To determine the species identity, genomic DNA from each isolate was extracted, and five loci were amplified, namely, part of the internal transcribed spacer (ITS) amplified with primers ITS1/ITS4 (White et al. 1990); part of the translation elongation factor 1-alpha (EF1-α) with primers EF1-728F/EF1-986R (Carbone and Kohn, 1999); part of the calmodulin (CAL) with primers CAL-228F/CAL-737R (Carbone and Kohn, 1999); part of the ß-tubulin (ß-tub) with primers Bt2a/Bt2b (Glass and Donaldson, 1995), and part of the histone H3 (HIS) with primers CYLH3F/H3-1b (Glass and Donaldson 1995, Crous et al., 2004). The obtained sequences were deposited in GenBank (accession numbers are listed in Table S1). BLAST analyses showed that the all the amplified fragments were highly homologous to Diaporthe spp. (Table S1). Based on concatenated sequences of the amplicons, a phylogenetic tree was constructed by using Maximum-likelihood and Bayesian inference methods. The multi-locus phylogenetic analyses distinguished SX-1 and SX-3 as D. cercidis, and SX-2 as D. nobilis. To complete Koch's postulates, the pathogenicity of SX-1, as well as SX-2, was tested on both detached and attached leaves of one-year-old Shanxin yang seedlings grown under greenhouse conditions. Healthy leaves were pierced with a sterile needle and then inoculated independently with 5-mm mycelial plugs cut from the edge of the 4-day-old colonies of SX-1 and SX-2 colonies. Controls were inoculated with noncolonized PDA plugs. Three replicates were prepared for each isolate. For the in-vitro tests, detached leaves were placed on wet filter paper in parafilm-sealed Petri dishes and cultured at 25 °C in the dark. For the attached leaf assays, the plants were kept in an 85% humidity chamber immediately after inoculation. All the inoculated leaves developed dark or brown necrotic lesions at 5 days after inoculation, whereas the control leaves showed no symptoms. D. cercidis and D. nobilis were separately reisolated from the inoculated leaves. The former was first described by Yang et al. (2018) as occurring on twigs and branches of Cercis chinensis, and very recently, this pathogen was reported to cause leaf blotch on Acer pictum subsp. mono (Wan et al., 2021). The latter infects some fruit trees (Yu et al., 2018; Sun et al., 2019; Ma et al., 2019) and chestnut (Zhang et al., 2018). All of these studies were conducted in China where there is a great diversity of Diaporthe species (Yang et al., 2018). To our knowledge, this is the first report of both D. cercidis and D. nobilis causing leaf blotch on poplar. The identification of these pathogens is essential for understanding the range of their host species and to manage the resulting fungal diseases, which may cause severe economic damage.

5.
Plant Physiol ; 180(4): 1788-1792, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31152128

RESUMO

Root sprouts-the formation of new shoots from roots-is an important mechanism for local gene flow from poplar (Populus spp). An effective strategy to reduce root sprout formation could therefore help to ensure containment during field research and commercial deployment of poplar when grown as exotic or transgenic forms. We used a flavonoid glycosyltransferase gene promoter from Scutellaria barbata (SbUGT) to drive the expression of AtCKX2, a cytokinin oxidase from Arabidopsis that converts active to inactive cytokinins in roots of poplar. In the greenhouse, SbUGT::AtCKX2 transgenic plants exhibited a similar shoot growth habit, but had enhanced root growth and fewer root sprouts, compared to the wild-type control and transgenic events with low transgene expression in roots. Under field conditions, the transgenic trees also had similar growth habits and stem growth rates that were not statistically different from wild-type trees over 3 years. Removal of trunks generally induced high rates of root sprouting; however, in selected SbUGT::AtCKX2 transgenic poplar events there was an absence or fewer root sprouts compared to wild-type trees, consistent with the greenhouse results. Our study demonstrates that the SbUGT::AtCKX2 gene can effectively inhibit root sprouting of poplar trees under field conditions, and thus may provide a useful tool to address concerns associated with root-sprouting-mediated transgene spread.


Assuntos
Citocininas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Populus/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Populus/genética , Regiões Promotoras Genéticas/genética
6.
Plant Dis ; 104(4): 1133-1143, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32049587

RESUMO

Identification of the particular genes in an R genes supercluster underlying resistance to the rust fungus Melampsora larici-populina in poplar genome remains challenging. Based on the de novo assembly of the Populus deltoides genome, all of the detected major genetic loci conferring resistance to M. larici-populina were confined to a 3.5-Mb region on chromosome 19. The transcriptomes of the resistant and susceptible genotypes were sequenced for a timespan from 0 to 168 hours postinoculation. By mapping the differentially expressed genes to the target genomic region, we identified two constitutive expression R genes and one inducible expression R gene that might confer resistance to M. larici-populina. Nucleotide variations were predicted based on the reconstructed haplotypes for each allele of the candidate genes. We also confirmed that salicylic acid was the phytohormone mediating signal transduction pathways, and PR-1 was identified as a key gene inhibiting rust reproduction. Finally, quantitative reverse transcription PCR assay revealed consistent expressions with the RNA-sequencing data for the detected key genes. This study presents an efficient approach for the identification of particular genes underlying phenotype of interest by the combination of genetic mapping, transcriptome profiling, and candidate gene sequences dissection. The identified key genes would be useful for host resistance diagnosis and for molecular breeding of elite poplar cultivars exhibiting resistance to M. larici-populina infection. The detected R genes are also valuable for testing whether the combination of individual R genes can induce durable quantitative resistance.


Assuntos
Basidiomycota , Populus , Perfilação da Expressão Gênica , Genes vpr , Doenças das Plantas
7.
Carcinogenesis ; 39(8): 981-992, 2018 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-29726904

RESUMO

Circular RNAs (circRNAs) are widespread and diverse endogenous RNAs distinct from traditional linear RNAs, which may regulate gene expression in eukaryotes. However, the function of human circRNAs, including their potential role in lung cancer, remains largely unknown. We screened the circRNA circ0006916, which was evidently down-regulated in 16HBE-T cells (anti-benzopyrene-trans-7, 8-dihydrodiol-9, 10-epoxide-transformed human bronchial epithelial cells), and in A549 and H460 cell lines. Silencing of circ0006916, but not its parental gene homer scaffolding protein 1 (HOMER1), promoted cell proliferation via speeding up the cell cycle process rather than by inhibiting apoptosis; conversely, overexpression of circ0006916 had the opposite effect. Luciferase-screening assay indicated that circ0006916 bound to miR-522-3p and inhibited pleckstrin homology domain and leucine rich repeat protein phosphatase 1 (PHLPP1) activity. We also explored the effect of the RNA-binding protein trinucleotide repeat-containing 6A (TNRC6A) on circ0006916 production. Circ0006916 expression was decreased after silencing TNRC6A. TNRC6A bound to the intron regions around the circRNA-forming exons of circ0006916, as shown by RNA immunoprecipitation assay combined with sequencing analysis. The association of circ0006916 with TNRC6A was further verified by RNA pull-down assays. We then constructed a carrier and confirmed that TNRC6A binding to the flanked intron region of circ0006916 was necessary for generation of circ0006916. These results demonstrate that TNRC6A regulates the biogenesis of the circRNA circ0006916, which has a regulatory role in cell growth.


Assuntos
Autoantígenos/metabolismo , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Proteínas de Ligação a RNA/metabolismo , RNA/metabolismo , Células A549 , Autoantígenos/genética , Inativação Gênica , Proteínas de Arcabouço Homer/genética , Humanos , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , Proteínas Nucleares/genética , Fosfoproteínas Fosfatases/genética , RNA/genética , RNA Circular , Proteínas de Ligação a RNA/genética
8.
Fish Shellfish Immunol ; 46(2): 378-86, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26118934

RESUMO

The non-specific immune parameters, disease resistance and immune genes expressions in Macrobrachium rosenbergii were evaluated at 120 days of post feeding the diets containing the extracts of banana, Musa acuminate, fruit's peel (banana peels extract, BPE) at 0, 1.0, 3.0 and 6.0 g kg(-1). Results showed that prawns fed with a diet containing BPE at the level of 1.0, 3.0 and 6.0 g kg(-1) for 120 days had a significantly higher survival rate (30.0%, 40.0% and 56.7%, respectively) than those fed with the control diet after challenge with Lactococcus garvieae for 144 h, and the respective relative survival percentages were 22.2%, 33.3%, and 51.9%, respectively. Dietary BPE supplementation at 3.0 and/or 6.0 g kg(-1) for 120 days showed a significant increase total haemocyte count (THC), granular cell (GC), superoxide dismutase (SOD) activity, phenoloxidase (PO) activity, transglutaminase (TG) activity, and phagocytic activity and clearance efficiency to L. garvieae infection, and meanwhile, the significant decrease in haemolymph clotting times and respiratory bursts (RBs) per haemocyte of prawns were revealed. Furthermore, the mRNA expressions of prophenoloxidase (proPO), lipopolysaccharide and ß-1,3-glucan binding protein (LGBP), peroxinectin (PE), transglutaminase (TG), and crustin (CT) were significantly increased. We therefore recommend that BPE can be used as an immunomodulator for prawns through dietary administration at 6.0 g kg(-1) for a long term (over 120 days) to modify immune responses and genes expression following the enhanced resistance against pathogens.


Assuntos
Resistência à Doença/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/imunologia , Lactococcus/patogenicidade , Musa , Palaemonidae/imunologia , Extratos Vegetais/farmacologia , Animais , Contagem de Células Sanguíneas , Dieta , Resistência à Doença/imunologia , Resistência à Doença/fisiologia , Frutas , Hemócitos/imunologia , Monofenol Mono-Oxigenase/metabolismo , Fagocitose/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Transcrição Gênica , Transglutaminases/genética , Transglutaminases/metabolismo
9.
Luminescence ; 30(8): 1360-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25829339

RESUMO

Using 2,4,6-tris-(2-pyridyl)-s-triazine (TPTZ) as a neutral ligand, and p-hydroxybenzoic acid, terephthalic acid and nitrate as anion ligands, five novel europium complexes have been synthesized. These complexes were characterized using elemental analysis, rare earth coordination titrations, UV/vis absorption spectroscopy and infrared spectroscopy. Luminescence spectra, luminescence lifetime and quantum efficiency were investigated and the mechanism discussed in depth. The results show that the complexes have excellent emission intensities, long emission lifetimes and high quantum efficiencies. The superior luminescent properties of the complexes may be because the triplet energy level of the ligands matches well with the lowest excitation state energy level of Eu(3+). Moreover, changing the ratio of the ligands and metal ions leads to different luminescent properties. Among the complexes, Eu2(TPTZ)2(C8H4O4)(NO3)4(C2H5OH)·H2O shows the strongest luminescence intensity, longest emission lifetime and highest quantum efficiency.


Assuntos
Európio/química , Substâncias Luminescentes/química , Triazinas/química , Luminescência , Substâncias Luminescentes/síntese química
10.
BMC Genomics ; 15: 612, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-25047956

RESUMO

BACKGROUND: All modern rosids originated from a common hexapolyploid ancestor, and the genomes of some rosids have undergone one or more cycles of paleopolyploidy. After the duplication of the ancient genome, wholesale gene loss and gene subfunctionalization has occurred. Using the extensin super-gene family as an example, we tracked the differential retention and expansion of ancestral extensin genes in four modern rosids, Arabidopsis, Populus, Vitis and Carica, using several analytical methods. RESULTS: The majority of extensin genes in each of the modern rosids were found to originate from different ancestral genes. In Arabidopsis and Populus, almost half of the extensins were paralogous duplicates within the genome of each species. By contrast, no paralogous extensins were detected in Vitis and Carica, which have only undergone the common γ-triplication event. It was noteworthy that a group of extensins containing the IPR006706 domain had actively duplicated in Arabidopsis, giving rise to a neo-extensin around every 3 million years. However, such extensins were absent from, or rare in, the other three rosids. A detailed examination revealed that this group of extensins had proliferated significantly in the genomes of a number of species in the Brassicaceae. We propose that this group of extensins might play important roles in the biology and in the evolution of the Brassicaceae. Our analyses also revealed that nearly all of the paralogous and orthologous extensin-pairs have been under strong purifying selection, leading to the strong conservation of the function of extensins duplicated from the same ancestral gene. CONCLUSIONS: Our analyses show that extensins originating from a common ancestor have been differentially retained and expanded among four modern rosids. Our findings suggest that, if Arabidopsis is used as the model plant, we can only learn a limited amount about the functions of a particular gene family. These results also provide an example of how it is essential to learn the origination of a gene when analyzing its function across different plant species.


Assuntos
Arabidopsis/genética , Carica/genética , Genes de Plantas , Populus/genética , Vitis/genética , Bases de Dados Genéticas , Glicoproteínas/classificação , Glicoproteínas/genética , Glicoproteínas/metabolismo , Filogenia , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poliploidia
11.
Mol Biol Rep ; 41(5): 3219-23, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24477589

RESUMO

In this study, single-nucleotide polymorphisms (SNPs) and insertions/deletions (InDels) in the genome of Ziziphus jujuba were identified using sequences generated by the Roche 454 GS-FLX sequencer. A total of, 573,141 reads were produced with an average read length of 360 bp. After quality control, 258,754 of the filtered reads were assembled into 23,864 contigs, and 293,458 remained as singletons. Using the contig assemblies as a reference, 17,160 SNPs and 478 InDels were identified. Among the SNPs, transitions occurred three times more frequently than transversions. In transitions, the number of C/T and G/A transitions was similar. Among the transversions, A/T was the most abundant, and C/G was much rarer than any of the other types of transversions, accounting for only about half the numbers of A/C, A/T and G/T transversions. For the InDels, mononucleotide changes amounted to 64.4% of the total number of InDels. In general, the frequency of detected InDels decreased as the length of the InDels increased. This study provides valuable marker resources for future genetic studies of Ziziphus spp.


Assuntos
Variação Genética , Genoma de Planta , Ziziphus/genética , Sequenciamento de Nucleotídeos em Larga Escala , Mutação INDEL , Polimorfismo de Nucleotídeo Único
12.
Food Chem ; 410: 135476, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36652794

RESUMO

To explore the effects of intramolecular neighboring groups on sulfhydryl group reactivity in acrylamide removal, the reactions of three sulfhydryl-containing flavoring substances with derived structures, 1-propanethiol, 3-mercaptopropionic acid, and cysteine, with acrylamide were investigated. The results showed that the activation energies of the reactions decreased with the introduction of amino and carboxyl groups. Additional comparison reactions showed that other proton acceptors also promote the reactions of sulfhydryl groups with acrylamide. However, the reactivity was not enhanced if the proton acceptor was located far from the sulfhydryl group. This suggested that sulfhydryl compounds with the molecular structure of proton acceptors on the carbons located ß or/and γ to the sulfhydryl group were efficient in eliminating acrylamide, and the results are expected to serve as a guide in the search for effective acrylamide elimination agents.


Assuntos
Acrilamida , Prótons , Acrilamida/química , Compostos de Sulfidrila/química , Cisteína/química , Estrutura Molecular
13.
Hortic Res ; 10(5): uhad042, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37188057

RESUMO

Labile sex expression is frequently observed in dioecious plants, but the underlying genetic mechanism remains largely unknown. Sex plasticity is also observed in many Populus species. Here we carried out a systematic study on a maleness-promoting gene, MSL, detected in the Populus deltoides genome. Our results showed that both strands of MSL contained multiple cis-activating elements, which generated long non-coding RNAs (lncRNAs) promoting maleness. Although female P. deltoides did not have the male-specific MSL gene, a large number of partial sequences with high sequence similarity to this gene were detected in the female poplar genome. Based on sequence alignment, the MSL sequence could be divided into three partial sequences, and heterologous expression of these partial sequences in Arabidopsis confirmed that they could promote maleness. Since activation of the MSL sequences can only result in female sex lability, we propose that MSL-lncRNAs might play a role in causing sex lability of female poplars.

14.
Environ Sci Pollut Res Int ; 30(35): 84011-84022, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37355513

RESUMO

Nowadays, clean-up of heavy metals from wastewaters using waste residue carbon-based material has received increasing attention. In this work, a novel Chinese medicine residue carbon-based nano zero-valent iron composite (CM-nZVI) had been successfully prepared using the combined Chinese medicine residue, FeCl3 and green tea extract. Cr(VI) and/ or Cd(II) removal in water by the CM-nZVI were systematacially investigated with a series of batch experiments. The most relevant findings indicated the adsorption efficiecy and capacity of Cr(VI) by CM-nZVI were respecitvely nearly 98% and 26 mg/g under optimized reaction conditions. The negative influences of the cations on the Cr(VI) removal followed the order of Al3+ > Ca2+ > Mg2+ Na+ > K+, but the anions followed the order of HCO3- > PO43- > NO3- > Cl- > SO42-. Humic acid (HA) and ionic strength with high concentrations severely inhibited Cr(VI) removal. The Cr(VI) adsorption on CM-nZVI fitted well by the pseudo-second-order kinetic and Langmuir models. A monolayer endothermic chemisorption occurred on Cr(VI) adsorption over CM-nZVI, and Cr(VI) removal by CM-nZVI primarily involved in the absorption, reduction, precipitation and complexation processes. Both Cr(VI) and Cd(II) removals had been achieved by CM-nZVI at their low concentrations. This CM-nZVI showed a better reusability proprity for Cr(VI) and Cd(II) removal with the regeneration of CM-nZVI through simple pickling. The outcomes of this work show that CM-nZVI could be used an effective material for heavy metals removal from water.


Assuntos
Carbono , Poluentes Químicos da Água , Cádmio , Ferro/química , Cinética , Poluentes Químicos da Água/análise , Cromo/química , Adsorção , Água/química
15.
Int J Biol Macromol ; 242(Pt 2): 124743, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37150377

RESUMO

The placenta in fruits of most plants either desiccate and shrink as the fruits mature or develop further to form the fleshy tissues. In poplars, placental epidermal cells protrude collectively to produce catkin fibers. In this study, three carpel limited MIXTA genes, PdeMIXTA02, PdeMIXTA03, PdeMIXTA04, were find to specifically expressed in carpel immediately after pollination. Heterologous expression of the three genes in Arabidopsis demonstrated that PdeMIXTA04 significantly promoted trichomes density and could restore trichomes in the trichomeless mutant. By contrast, such functions were not observed with PdeMIXTA02, PdeMIXTA03. In situ hybridization revealed that PdeMIXTA04 was explicitly expressed in poplar placental epidermal cells. We also confirmed trichome-specific expression of the PdeMIXTA04 promoter. Multiple experimental proofs have confirmed the interaction between PdeMIXTA04, PdeMYC and PdeWD40, indicating PdeMIXTA04 functioned through the MYB-bHLH-WD40 ternary complex. Our work provided distinctive understanding of the molecular mechanism triggering differentiation of poplar catkins.


Assuntos
Diferenciação Celular , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Cone de Plantas , Epiderme Vegetal , Proteínas de Plantas , Populus , Epiderme Vegetal/citologia , Epiderme Vegetal/genética , Epiderme Vegetal/crescimento & desenvolvimento , Populus/citologia , Populus/genética , Populus/crescimento & desenvolvimento , Arabidopsis , Diferenciação Celular/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Polinização , Cone de Plantas/genética , Cone de Plantas/crescimento & desenvolvimento
16.
Curr Neuropharmacol ; 21(1): 142-150, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35927806

RESUMO

It has been reported in the previous literatures that high-frequency (HF) neuronavigated repetitive transcranial magnetic stimulation (rTMS) may improve neurocognitive functioning in patients with schizophrenia. Nonetheless, the heterogeneity of the research findings with regards to the effectiveness of HF-rTMS on the neurocognitive functioning in patients with schizophrenia greatly hinders its clinical application. The current study was designed to determine the predictive role of BDNF variants for neurocognitive improvements after rTMS administration in veterans with schizophrenia. 109 hospitalized veterans with schizophrenia were randomly allocated to active HF-rTMS (n=63) or sham stimulation (n=46) over left DLPFC for 4 consecutive weeks. Neurocognitive functions were assessed by using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) at baseline and at the end of week 4. BDNF polymorphism was genotyped by the technicians. Compared with sham stimulation sessions, the immediate memory performance was significantly increased in active sessions after neuronavigated HF-rTMS administration. In addition, patients with the CC homozygotes demonstrated greater improvement of immediate memory after rTMS treatment, while T allele carriers showed no significant improvement in immediate memory domain relative to baseline performance of immediate memory. Our findings suggest that add-on neuronavigated HF-rTMS is beneficial on immediate memory only in patients with CC homozygotes, but not in T allele carriers. This pilot study provides further evidence for BDNF as a promise biomarker in predicting the clinical response to rTMS stimulation.


Assuntos
Esquizofrenia , Veteranos , Humanos , Esquizofrenia/complicações , Esquizofrenia/genética , Esquizofrenia/terapia , Fator Neurotrófico Derivado do Encéfalo/genética , Resultado do Tratamento , Projetos Piloto , Estimulação Magnética Transcraniana , Córtex Pré-Frontal
17.
Curr Neuropharmacol ; 21(2): 417-423, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35611778

RESUMO

OBJECTIVES: There is emerging evidence that high-frequency (HF) repetitive transcranial magnetic stimulation (rTMS) may promote weight loss in individuals with obesity in the general population. However, no study has been conducted on patients with schizophrenia (SZ). This study evaluated the efficacy of 10Hz rTMS in reducing body weight in patients with chronic SZ. METHODS: Forty-seven SZ patients were randomly assigned to two groups: 10Hz rTMS or sham stimulation over DLPFC (applied once daily) for 20 consecutive treatments. Body weight was assessed at baseline, at the end of week 1, week 2, week 3 and week 4. Clinical symptoms were evaluated with the Positive and Negative Syndrome Scale (PANSS) at baseline and at the end of week 4. RESULTS: We found that compared with patients in the sham group, 10Hz rTMS treatment significantly reduced body weight in patients with chronic SZ after a period of 4 weeks of stimulation. Interestingly, further analysis found that from the first week (5 sessions) of treatment, there was a significant difference in body weight between active and sham groups after controlling for baseline weight. However, active rTMS treatment did not improve the psychotic symptoms compared to sham stimulation. CONCLUSION: Our results suggest that add-on HF rTMS could be an effective therapeutic strategy for body weight control in patients with chronic SZ.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/diagnóstico , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento , Córtex Pré-Frontal , Redução de Peso/fisiologia , Peso Corporal/fisiologia , Método Duplo-Cego
18.
Mol Cancer Ther ; 22(2): 215-226, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36228090

RESUMO

CRISPR Cas9-based screening is a powerful approach for identifying and characterizing novel drug targets. Here, we elucidate the synthetic lethal mechanism of deubiquitinating enzyme USP1 in cancers with underlying DNA damage vulnerabilities, specifically BRCA1/2 mutant tumors and a subset of BRCA1/2 wild-type (WT) tumors. In sensitive cells, pharmacologic inhibition of USP1 leads to decreased DNA synthesis concomitant with S-phase-specific DNA damage. Genome-wide CRISPR-Cas9 screens identify RAD18 and UBE2K, which promote PCNA mono- and polyubiquitination respectively, as mediators of USP1 dependency. The accumulation of mono- and polyubiquitinated PCNA following USP1 inhibition is associated with reduced PCNA protein levels. Ectopic expression of WT or ubiquitin-dead K164R PCNA reverses USP1 inhibitor sensitivity. Our results show, for the first time, that USP1 dependency hinges on the aberrant processing of mono- and polyubiquitinated PCNA. Moreover, this mechanism of USP1 dependency extends beyond BRCA1/2 mutant tumors to selected BRCA1/2 WT cancer cell lines enriched in ovarian and lung lineages. We further show PARP and USP1 inhibition are strongly synergistic in BRCA1/2 mutant tumors. We postulate USP1 dependency unveils a previously uncharacterized vulnerability linked to posttranslational modifications of PCNA. Taken together, USP1 inhibition may represent a novel therapeutic strategy for BRCA1/2 mutant tumors and a subset of BRCA1/2 WT tumors.


Assuntos
Neoplasias , Mutações Sintéticas Letais , Humanos , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ubiquitina/genética , Ubiquitinação , Dano ao DNA , Neoplasias/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo
19.
Plant Biotechnol J ; 10(2): 139-49, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21777365

RESUMO

Crop architecture parameters such as tiller number, angle and plant height are important agronomic traits that have been considered for breeding programmes. Auxin distribution within the plant has long been recognized to alter architecture. The rice (Oryza sativa L.) genome contains 12 putative PIN genes encoding auxin efflux transporters, including four PIN1 and one PIN2 genes. Here, we report that over-expression of OsPIN2 through a transgenic approach in rice (Japonica cv. Nipponbare) led to a shorter plant height, more tillers and a larger tiller angle when compared with wild type (WT). The expression patterns of the auxin reporter DR5::GUS and quantification of auxin distribution showed that OsPIN2 over-expression increased auxin transport from the shoot to the root-shoot junction, resulting in a non-tissue-specific accumulation of more free auxin at the root-shoot junction relative to WT. Over-expression of OsPIN2 enhanced auxin transport from shoots to roots, but did not alter the polar auxin pattern in the roots. Transgenic plants were less sensitive to N-1-naphthylphthalamic acid, an auxin transport inhibitor, than WT in their root growth. OsPIN2-over-expressing plants had suppressed the expression of a gravitropism-related gene OsLazy1 in the shoots, but unaltered expression of OsPIN1b and OsTAC1, which were reported as tiller angle controllers in rice. The data suggest that OsPIN2 has a distinct auxin-dependent regulation pathway together with OsPIN1b and OsTAC1 controlling rice shoot architecture. Altering OsPIN2 expression by genetic transformation can be directly used for modifying rice architecture.


Assuntos
Oryza/crescimento & desenvolvimento , Oryza/genética , Proteínas de Plantas/genética , Proteína 1 de Ligação a Repetições Teloméricas/genética , Transporte Biológico , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Gravitropismo/genética , Ácidos Indolacéticos/metabolismo , Oryza/anatomia & histologia , Oryza/metabolismo , Ftalimidas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/biossíntese , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Proteína 1 de Ligação a Repetições Teloméricas/biossíntese
20.
Cancer Cell ; 5(1): 91-102, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14749129

RESUMO

Key molecular lesions in colorectal and other cancers cause beta-catenin-dependent transactivation of T cell factor (Tcf)-dependent genes. Disruption of this signal represents an opportunity for rational cancer therapy. To identify compounds that inhibit association between Tcf4 and beta-catenin, we screened libraries of natural compounds in a high-throughput assay for immunoenzymatic detection of the protein-protein interaction. Selected compounds disrupt Tcf/beta-catenin complexes in several independent in vitro assays and potently antagonize cellular effects of beta-catenin-dependent activities, including reporter gene activation, c-myc or cyclin D1 expression, cell proliferation, and duplication of the Xenopus embryonic dorsal axis. These compounds thus meet predicted criteria for disrupting Tcf/beta-catenin complexes and define a general standard to establish mechanism-based activity of small molecule inhibitors of this pathogenic protein-protein interaction.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Transdução de Sinais/fisiologia , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Animais , Células COS , Divisão Celular/fisiologia , Chlorocebus aethiops , Técnicas de Química Combinatória , Ciclina D1/metabolismo , Ligação Proteica , Ressonância de Plasmônio de Superfície , Xenopus/metabolismo , Proteínas de Xenopus , beta Catenina
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