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1.
Eur J Med Chem ; 268: 116229, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430852

RESUMO

Betel-quid chewing addiction is the leading cause of oral submucous fibrosis and oral cancer, resulting in significant socio-economic burdens. Vaccination may serve as a promising potential remedy to mitigate the abuse and combat accidental overdose of betel nut. Hapten design is the crucial factor to the development of arecoline vaccine that determines the efficacy of a candidate vaccine. Herein, we reported that two kinds of novel arecoline-based haptens were synthesized and conjugated to Bovine Serum Albumin (BSA) to generate immunogens, which generated antibodies with high affinity for arecoline but reduced binding for guvacoline and no affinity for arecaidine or guvacine. Notably, vaccination with Arec-N-BSA, which via the N-position on the tetrahydropyridine ring (tertiary amine group), led to a higher antibody affinity compared to Arec-CONH-BSA, blunted analgesia and attenuated hypothermia for arecoline.


Assuntos
Arecolina , Transtornos Relacionados ao Uso de Substâncias , Arecolina/farmacologia , Arecolina/metabolismo , Vacinas Conjugadas , Areca/metabolismo
2.
World J Gastrointest Oncol ; 15(11): 1936-1950, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38077650

RESUMO

BACKGROUND: Dopamine and cyclic adenosine monophosphate (cAMP)-regulated phosphoprotein with an apparent Mr of 32000 (DARPP-32) is a protein that is involved in regulating dopamine and cAMP signaling pathways in the brain. However, recent studies have shown that DARPP-32 is also expressed in other tissues, including colorectal cancer (CRC), where its function is not well understood. AIM: To explore the effect of DARPP-32 on CRC progression. METHODS: The expression levels of DARPP-32 were assessed in CRC tissues using both quantitative polymerase chain reaction and immunohistochemistry assays. The proliferative capacity of CRC cell lines was evaluated with Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine assays, while apoptosis was measured by flow cytometry. The migratory and invasive potential of CRC cell lines were determined using wound healing and transwell chamber assays. In vivo studies involved monitoring the growth rate of xenograft tumors. Finally, the underlying molecular mechanism of DARPP-32 was investigated through RNA-sequencing and western blot analyses. RESULTS: DARPP-32 was frequently upregulated in CRC and associated with abnormal clinicopathological features in CRC. Overexpression of DARPP-32 was shown to promote cancer cell proliferation, migration, and invasion and reduce apoptosis. DARPP-32 knockdown resulted in the opposite functional effects. Mechanistically, DARPP-32 may regulate the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway in order to carry out its biological function. CONCLUSION: DARPP-32 promotes CRC progression via the PI3K/AKT signaling pathway.

3.
Molecules ; 28(19)2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37836811

RESUMO

Recently, non-fullerene-based organic solar cells (OSCs) have made great breakthroughs, and small structural differences can have dramatic impacts on the power conversion efficiency (PCE). We take ITIC and its isomers as examples to study their effects on the performance of OSCs. ITIC and NFBDT only differed in the side chain position, and they were used as models with the same donor molecule, PBDB-T, to investigate the main reasons for the difference in their performance in terms of theoretical methods. In this work, a detailed comparative analysis of the electronic structure, absorption spectra, open circuit voltage and interfacial parameters of the ITIC and NFBDT systems was performed mainly by combining the density functional theory/time-dependent density functional theory and molecular dynamics simulations. The results showed that the lowest excited state of the ITIC molecule possessed a larger ∆q and more hybrid FE/CT states, and PBDB-T/ITIC had more charge separation paths as well as a larger kCS and smaller kCR. The reason for the performance difference between PBDB-T/ITIC and PBDB-T/NFBDT was elucidated, suggesting that ITIC is a superior acceptor based on a slight modulation of the side chain and providing a guiding direction for the design of superior-performing small molecule acceptor materials.

4.
Brain Behav ; 12(7): e2636, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35674485

RESUMO

OBJECTIVE: To explore the effects of the autonomous sensory meridian response (ASMR) on the psychological cravings and anxiety of women compulsorily isolated for detoxification. METHOD: Around 122 women were recruited in a female drug detoxification center. Except for the 12-week training of ASMR, the experimental conditions of the experimental group (n = 60) were the same as those of the control group (n = 62). The addiction Stroop task was used to assess the level of psychological cravings and the State-Trait Anxiety Inventory was used to assess the level of anxiety. RESULTS: After the training, the decrease in state anxiety of the experimental group was larger than that of the control group, and the reaction time of the experimental group in the Stroop was also significantly lower than before the training. CONCLUSIONS: ASMR could thus reduce to a certain extent the state anxiety and attentional bias for drug-related clues under signaling psychological cravings among women compulsorily isolated for detoxification. HIGHLIGHTS: Intervention effects on psychological cravings and anxiety of women isolated for detoxification Basis for role of ASMR in regulating psychological cravings and anxiety in forced abstainers ASMR intervention reduced forced abstainers' attentional bias to drug-related clues.


Assuntos
Fissura , Meridianos , Ansiedade/psicologia , Ansiedade/terapia , Transtornos de Ansiedade , Feminino , Humanos , Teste de Stroop
5.
Anal Chem ; 93(31): 11019-11024, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34324804

RESUMO

Au nanoparticles (Au NPs) can be self-assembled in a bottom-up orderly manner at the oil-water interface, which is widely used as SERS platforms, but the stability of the Au NP interface needs to be improved due to shaking or shifting and the Brownian motion. The DNA structure with unique sequence specificity, excellent programmability, and flexible end-group modification capability owns good potential to precisely control the plasmonic structure's distance. In this study, a large area of the SERS substrate is obtained from the DNA structure-stabilized self-assembled ordered Au NPs on the cyclohexane-water interface. Combining with the exonuclease III (exo III)-assisted DNA recycling amplification strategy, we construct a liquid-phase SERS biosensor for efficient detection of microRNA 155 (miRNA 155). Compared with the traditional randomly assembled Au NPs on the two-phase interface, the SERS signal is significantly enhanced and more stable. The detection limit of the SERS biosensor for miRNA 155 reached 1.45 fmol/L, which has a very wide linear range (100 fmol/L-5 nmol/L). This work gives an efficient approach to stabilize the self-assembly Au NPs on the liquid-liquid interface, which can broaden the application of SERS analysis.


Assuntos
Nanopartículas Metálicas , MicroRNAs , DNA , Ouro , Análise Espectral Raman
6.
Theranostics ; 11(11): 5464-5490, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859758

RESUMO

Hepatocellular carcinoma (HCC) is the most common type of liver cancer and one of the leading causes of cancer-related death worldwide. Advanced HCC displays strong resistance to chemotherapy, and traditional chemotherapy drugs do not achieve satisfactory therapeutic efficacy. Sorafenib is an oral kinase inhibitor that inhibits tumor cell proliferation and angiogenesis and induces cancer cell apoptosis. It also improves the survival rates of patients with advanced liver cancer. However, due to its poor solubility, fast metabolism, and low bioavailability, clinical applications of sorafenib have been substantially restricted. In recent years, various studies have been conducted on the use of nanoparticles to improve drug targeting and therapeutic efficacy in HCC. Moreover, nanoparticles have been extensively explored to improve the therapeutic efficacy of sorafenib, and a variety of nanoparticles, such as polymer, lipid, silica, and metal nanoparticles, have been developed for treating liver cancer. All these new technologies have improved the targeted treatment of HCC by sorafenib and promoted nanomedicines as treatments for HCC. This review provides an overview of hot topics in tumor nanoscience and the latest status of treatments for HCC. It further introduces the current research status of nanoparticle drug delivery systems for treatment of HCC with sorafenib.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas/química , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Animais , Sistemas de Liberação de Medicamentos/métodos , Humanos
7.
Ecotoxicol Environ Saf ; 207: 111308, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32931972

RESUMO

Pogonatherum crinitum is a promising lead (Pb) hyperaccumulator; however, the effects of Pb contamination on P. crinitum rhizosphere soil enzymatic activities and microbial composition remain largely unexplored. Thus, an indoor experiment was conducted by cultivating P. crinitum seedlings and exposing them to four Pb concentrations (0, 1,000, 2000 and 3000 mg/kg Pb). Protease, urease, acid phosphatase and invertase activities were determined using standard methods while soil bacterial composition was determined by 16 S rDNA sequencing. The results showed that rhizosphere soil acid phosphatase activity significantly increased with increasing Pb concentration, while urease activity was significantly greater in rhizosphere soil contaminated with 1000 and 2000 mg/kg than in the control. There was a clear shift in bacterial composition during phytoremediation by P. crinitum. Compared to the control, Bacteroidetes was more abundant in all Pb-contaminated soils, Actinobacteria was more abundant in 1000 mg/kg Pb-treated soil, and Firmicutes was more abundant in 3000 mg/kg Pb-treated soil. Positive correlations were observed between dominant bacterial phyla and soil enzyme activities. Metabolic pathways, such as ABC transporter, quinine reductase, and ATP-binding protein were significantly increased in rhizosphere soil bacteria with Pb contamination. In conclusion, Pb contamination differentially influenced the activities of rhizosphere soil enzymes, specifically increasing acid phosphatase and urease activities, and alters the dominance of soil bacteria through up-regulation of genes related to some metabolic pathways. The strong correlations between dominant bacterial phyla and enzymatic activities suggest synergetic effects on the growth of P. crinitum during Pb contamination.


Assuntos
Bioacumulação , Chumbo/toxicidade , Poaceae/efeitos dos fármacos , Poaceae/enzimologia , Rizosfera , Microbiologia do Solo , Poluentes do Solo/toxicidade , Fosfatase Ácida/metabolismo , Actinobacteria/efeitos dos fármacos , Actinobacteria/enzimologia , Biodegradação Ambiental , Chumbo/metabolismo , Peptídeo Hidrolases/metabolismo , Poaceae/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Plântula/metabolismo , Solo/química , Poluentes do Solo/metabolismo , Urease/metabolismo
8.
Biochem Biophys Res Commun ; 503(2): 671-676, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29908182

RESUMO

Intracellular protein delivery is of significance for cellular protein analysis and therapeutic development, but remains challenging technically. Herein, we report a general and highly potent strategy for intracellular protein delivery based on commercially available cationic lipids. In this strategy, a designed double branching poly-glutamate tag is site-specifically attached onto the C-terminal of protein cargos via expressed protein ligation (EPL), which mediates the entrapment of proteins into cationic liposomes driven by electrostatic interaction. The resultant protein-lipid complexes can enter into cytosol with a high efficiency even at the low protein concentration while maintaining protein's biological activity.


Assuntos
Ácido Glutâmico/análogos & derivados , Lipídeos/química , Lipossomos/química , Proteínas/administração & dosagem , Células A549 , Sequência de Aminoácidos , Cátions/química , Células HeLa , Humanos , Peptídeos/química , Proteínas/química , Eletricidade Estática , Transfecção
9.
Ultrason Sonochem ; 38: 9-18, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28633861

RESUMO

This study investigated for the first time the feasibility of using a magnetic field for sludge disintegration. Approximately 41.01% disintegration degree (DD) was reached after 30min at 180mT magnetic field intensity upon separate magnetic field treatment. Protein and polysaccharide contents significantly increased. This test was optimized using a Box-Behnken design (BBD) with response surface methodology (RSM) to fit the multiple equation of the DD. The maximum DD was 43.75% and the protein and polysaccharide contents increased to 56.71 and 119.44mg/L, respectively, when the magnetic field strength was 119.69mT, reaction time was 30.49min, and pH was 9.82 in the optimization experiment. We then analyzed the effects of ultrasound alone. We are the first to combine magnetic field with ultrasound to disintegrate waste-activated sludge (WAS). The optimum effect was obtained with the application of ultrasound alone at 45kHz frequency, with a DD of about 58.09%. By contrast, 62.62% DD was reached in combined magnetic field and ultrasound treatment. This combined test was also optimized using BBD with RSM to fit the multiple equation of DD. The maximum DD of 64.59% was achieved when the magnetic field intensity was 197.87mT, ultrasonic frequency was 42.28kHz, reaction time was 33.96min, and pH was 8.90. These results were consistent with those of particle size and electron microscopy analyses. This research proved that a magnetic field can effectively disintegrate WAS and can be combined with other physical techniques such as ultrasound for optimal results.


Assuntos
Campos Magnéticos , Esgotos , Sonicação , Gerenciamento de Resíduos/métodos , Concentração de Íons de Hidrogênio , Fatores de Tempo
11.
Plant Cell Physiol ; 53(7): 1283-94, 2012 07.
Artigo em Inglês | MEDLINE | ID: mdl-22619471

RESUMO

The present study identified Arabidopsis miR394 and its target, an F-box (SKP1-Cullin/CDC53-F-box) gene At1g27340 (here referred to as LEAF CURLING RESPONSIVENESS, LCR), for regulation of leaf curling-related morphology. The loss-of-function lcr mutants exhibit pleiotropic defects with semi-dwarfism, altered leaf shape and a shorter stem. Overexpression of an miR394-resistant version of LCR under the 35S promoter (35S:m5LCR) and target mimicry MIM394 resulted in a curled-down leaf defect. Conversely, transgenic plants overexpressing 35S:MIR394a/b display a curled-up leaf phenotype. Detailed analyses show that there is a certain level of LCR that is optimal for leaf morphology, but lower or higher levels lead to abnormal leaf development, indicating that expression of miR394 in the leaf lamina is necessary for proper leaf morphology. Because the phytohormone auxin plays a crucial role in leaf morphogenesis and patterning, the DR5-GUS reporter gene was used to monitor the auxin response. We show that DR5 expression patterns in lcr and 35S::m5LCR plants were significantly different from those in the wild type. Also, overexpression of LCR in 35S::m5LCR plants drastically decreased the expression of the auxin-responsive genes IAA3, AXR3 and IAMT1, whereas increased expression of the genes was found in 35S::MIR394a plants. These results indicate that miR394 and its target LCR are involved in the regulation of leaf development.


Assuntos
Arabidopsis/genética , MicroRNAs/metabolismo , Folhas de Planta/fisiologia , RNA de Plantas/metabolismo , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/metabolismo , Sequência de Aminoácidos , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cromossomos de Plantas/genética , Cromossomos de Plantas/metabolismo , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genes Reporter , Ácidos Indolacéticos/metabolismo , MicroRNAs/genética , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fenótipo , Folhas de Planta/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/fisiologia , Regiões Promotoras Genéticas , RNA de Plantas/genética , Fatores de Transcrição , Transformação Genética
12.
J Plant Physiol ; 167(15): 1289-97, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20591534

RESUMO

Phosphorus is one of the major factors controlling plant growth and productivity. Although physiological and molecular processes of P deficiency have been intensively investigated, our current understanding of the coordinated regulation of phosphate-responsive genes and signal networks is limited. In the present study, we performed a microarray-based genome-wide transcriptional analysis of miRNAs from soybean (Glycine max L.) under phosphate deficiency. miRNAs extracted from P-deficient and P-sufficient soybean were hybridized to an array containing 853 known plant miRNA sequences. An induction ratio significant at p<0.01 was observed for 57 miRNAs belonging to 27 families. Among these miRNA families, which differentially expressed, 7 and 8 were found to be up-regulated, whereas 17 and 6 were down-regulated in leaves and roots, respectively. Seven representative individual miRNAs were selected for qRT-PCR validation, and most showed an expression pattern similar to that on microarray. We further predicted P-responsive cis-elements from the promoters of miRNAs in response to and non-responding to P deficiency. In total, 125 putative cis-elements were identified for 24 soybean P-deficient responsive miRNAs. Interestingly, those miRNAs (54) not responding to P deficiency were also found to contain the same P-responsive motifs. A comparative analysis revealed that the frequency of the motif occurrence in the promoters of miRNA genes in response to P deficiency was higher than that of miRNA genes not responding to P deficiency. Our study provides initial evidence in soybean that a set of miRNAs with a high frequency of P-responsive cis-elements may coordinately regulate the plant response to P deficiency.


Assuntos
Glycine max/genética , MicroRNAs/genética , Fósforo/deficiência , Sequências Reguladoras de Ácido Nucleico/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , MicroRNAs/metabolismo , Fósforo/farmacologia , Regiões Promotoras Genéticas/genética , Reprodutibilidade dos Testes , Glycine max/efeitos dos fármacos , TATA Box/genética , Sítio de Iniciação de Transcrição
13.
Plant Biotechnol J ; 8(8): 887-99, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20444207

RESUMO

MicroRNAs (miRNAs) are a class of short endogenous non-coding small RNAs that can base pair their target mRNAs to repress their translation or induce their degradation in organisms. However, whether miRNAs are involved in the global response to sulphate deficiency and heavy metal stress is unknown. In this study, we constructed a small RNA library from rapeseed (Brassica napus) treated with sulphate deficiency and cadmium (Cd²+), respectively. Sequencing analysis revealed 13 conserved miRNAs representing nine families, with five new miRNAs that have not been cloned before. Transcriptional analysis with RT-PCR showed the differential expression of these miRNAs under sulphate deficiency and Cd exposure. We have cloned five genes BnSultr2;1 and BnAPS1-4, which encode a low-affinity sulphate transporter and a family of ATP sulphurylases in B. napus, respectively. BnSultr2;1, BnAPS3 and BnAPS4 were first cloned from B. napus, and BnSultr2;1, BnAPS1, BnAPS3 and BnAPS4 were identified as the targets of miR395. Analysis with 5'-RACE and transformation of MIR395d into B. napus confirmed that all of them were the authentic targets of miR395. Our results support the importance of miRNAs in regulating plant responses to abiotic stresses and suggest that identification of a set of miRNAs would facilitate our understanding of regulatory mechanisms for plant tolerance to sulphate deficiency and heavy metal stress.


Assuntos
Brassica napus/genética , Brassica napus/metabolismo , Cádmio/toxicidade , MicroRNAs/genética , RNA de Plantas/metabolismo , Sulfatos/metabolismo , Brassica napus/efeitos dos fármacos , RNA de Plantas/genética , RNA de Plantas/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Poluentes do Solo/toxicidade , Estresse Fisiológico/efeitos dos fármacos
14.
J Inorg Biochem ; 103(2): 282-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19081140

RESUMO

MicroRNAs (miRNAs) are a novel class of short, endogenous non-coding small RNAs that have the ability to base pair with their target mRNAs to repress their translation or induce their degradation in both plants and animals. To identify heavy metal stress-regulated novel miRNAs, we constructed a library of small RNAs from rice seedlings that were exposed to toxic levels of cadmium (Cd(2+)). Sequencing of the library and subsequent analysis revealed 19 new miRNAs representing six families. These cloned new rice miRNAs have sequence conservation neither in Arabidopsis nor in any other species. Most of the new rice miRNAs were up- or down-regulated in response to the metal exposure. On the base of sequence complementarity, a total of 34 miRNA targets were predicted, of which 23 targets are functionally annotated and the other 11 records belong to unknown proteins. Some predicted targets of miRNAs are associated with the regulation of the response to heavy metal-induced stresses. In addition to the new miRNAs, we detected nine previously reported miRNAs and 56 other novel endogenous small RNAs in rice. These findings suggest that the number of new miRNAs in rice is unsaturated and some of them may play critical roles in plant responses to environmental stresses.


Assuntos
Cádmio/metabolismo , MicroRNAs/química , Oryza/metabolismo , Clonagem Molecular , Sequência Conservada , Regulação da Expressão Gênica de Plantas , Genes de Plantas , MicroRNAs/genética , MicroRNAs/metabolismo , Oryza/genética
15.
Biochem Biophys Res Commun ; 374(3): 538-42, 2008 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-18662674

RESUMO

MicroRNAs (miRNAs) are a class of non-protein coding small RNAs that regulate gene post-transcriptional expression in plants and animals. Although more than 1280 miRNAs in plant kingdom have been discovered thus far, only a handful of plant miRNAs has been intensively identified. The legume Medicago truncatula is a model system widely used to investigate gene transcription or post-transcriptional processes for arbuscular mycorrhiza development. In this study, we used a bioinformatics approach for ESTs (Expressed Sequence Tags)- and GSS (Genomic Survey Sequences)-wide prediction of novel miRNAs in M. truncatula. A total of 38 potential miRNAs were detected following a range of filtering criteria. After removal of 12 overlapping miRNAs that have already been deposited in miRNA Registry (Release 11.0), 26 miRNAs belonging to 15 families were found to be new. Using the newly identified miRNA sequences, we were able to further blast the M. truncatula mRNA database and detected 16 potential targets of miRNAs. Many miRNA targeted genes were predicted to encode transcription factors that regulate plant development, signaling, and metabolism. To verify the prediction of the miRNAs in M. truncatula, the qRT-PCR-based assay was performed. Our results showed that eight of the miRNA families displayed different patterns of expression in tissues. Additionally, expression of these miRNAs was up- or down-regulated by heavy metals (Hg, Cd, and Al). The above results implied that some of the miRNAs are involved in the regulation of development and plant response to heavy metal stress.


Assuntos
Regulação da Expressão Gênica de Plantas , Medicago truncatula/genética , MicroRNAs/genética , RNA de Plantas/genética , Biologia Computacional , Regulação para Baixo , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Variação Genética , Medicago truncatula/efeitos dos fármacos , Metais Pesados/farmacologia , MicroRNAs/classificação , RNA de Plantas/classificação
16.
Gene ; 395(1-2): 49-61, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17408884

RESUMO

MicroRNAs (miRNAs) are a class of non-coding RNAs that regulate gene post-transcriptional expression in animals and plants. Comparatively genomic computational methods have been developed to predict new miRNAs in worms, humans, and Arabidopsis. Here we present an EST (Expressed Sequence Tags)--and GSS (Genomic Survey Sequences)-based combined approach for the detection of novel miRNAs in Gossypium hirsutum. This was initiated by using previously known miRNA sequences from Arabidopsis, rice and other plant species and an algorithm called miRNAassist to blast the databases of G. hirsutum EST and GSS. A total of 37 potential miRNAs were detected following a range of filtering criteria. Using these potential miRNAs sequences, we further blasted the publicly available mRNA database and detected 96 potential targets in G. hirsutum. According to the mRNA information provided by the National Center for Biotechnology Information (NCBI) (http://www.ncbi.nlm.nih.gov/), most of the miRNA targeted genes were predicted to encode transcription factors that regulate cell growth and development, signaling, and metabolism. So far, little is known about experimental or computational identification of miRNA in G. hirsutum species. These new miRNAs and their targets in G. hirsutum have been run through miRNAassist to yield data that may help us better understanding of the possible role of miRNAs in regulating the growth and development of G. hirsutum.


Assuntos
Gossypium/genética , MicroRNAs/genética , RNA de Plantas/genética , Algoritmos , Sequência de Bases , Etiquetas de Sequências Expressas , Genômica/métodos , Genômica/estatística & dados numéricos , Gossypium/crescimento & desenvolvimento , MicroRNAs/química , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA de Plantas/química
17.
FEBS Lett ; 581(7): 1464-74, 2007 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-17367786

RESUMO

MicroRNAs (miRNAs) are a newly discovered class of non-protein-coding small RNAs with roughly 22 nucleotide-long. Increasing evidence has shown that miRNAs play multiple roles in biological processes, including development, cell proliferation and apoptosis and stress responses. In this research, several approaches were combined to make computational prediction of potential miRNAs and their targets in Brassica napus. We used previously known miRNAs from Arabidopsis, rice and other plant species against both expressed sequence tags (EST) and genomic survey sequence (GSS) databases to search for potential miRNAs in B. napus. A total of 21 potential miRNAs were detected following a range of strict filtering criteria. Using these potential miRNA sequences, we could further blast the mRNA database and found 67 potential targets in this species. According to the mRNA target information provided by NCBI (http://www.ncbi.nlm.nih.gov/), most of the target mRNAs appeared to be involved in plant growth, development and stress responses. To validate the prediction of miRNAs in B. napus, we performed a RT-PCR based assay of mature miRNA expression. Five miRNAs were identified in response to auxin, cadmium stress and phosphate starvation. So far, little is known about experimental or computational identification of miRNA in B. napus species. To improve efficiency for blast search, we developed an implementation (miRNAassist) that can identify homologs of miRNAs and their targets, with high sensitivity and specificity. The program is allowed to be run on Windows Operation System platform. miRNAassist is freely available if required.


Assuntos
Brassica napus/genética , Biologia Computacional/métodos , MicroRNAs/genética , RNA de Plantas/genética , Software , Sequência de Bases , Brassica napus/metabolismo , Bases de Dados de Ácidos Nucleicos , Etiquetas de Sequências Expressas , Regulação da Expressão Gênica de Plantas , MicroRNAs/isolamento & purificação , MicroRNAs/metabolismo , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA de Plantas/isolamento & purificação , RNA de Plantas/metabolismo , Análise de Sequência de RNA/métodos
18.
J Inorg Biochem ; 101(1): 1-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17084899

RESUMO

Alfalfa (Medicago sativa) roots were treated with mercuric ions in a concentration- and time-dependent manner, and lipid peroxidation was studied biochemically as well as histochemically along with other physiological responses. Histochemical staining with Schiff's reagent and Evans blue revealed that the peroxidation of membrane lipids and loss of plasma membrane integrity in Hg-treated roots occurred in the meristem and the elongation zone. The histochemical observations were supported by the quantitative determinations of thiobarbituric acid reactive substances (TBARS). However, under the mercuric ions stress, the alfalfa plants showed no significant alteration of hydrogen peroxide in roots. Analysis of lipoxygenase activity by non-denaturing polyacrylamide gel electrophoresis (PAGE) showed that there were two isoforms in the root of alfalfa plants, but they showed quite different patterns under the Hg exposure. Also, using non-denaturing PAGE, activities of superoxide dismutase (SOD) and peroxidase (POD) were determined in roots after treatment with Hg ions. The total activities of SOD and POD increased in roots after Hg treatment of roots. Activity of ascorbate peroxides (APX) was stimulated at relatively high concentration of Hg (40microM), and after prolonged Hg exposure (20microM, 24h). In contrast, glutathione reductase activity was depressed at higher concentrations of Hg (10-20microM). Treatments of seedlings with 10-40microM Hg decreased the ascorbate and glutathione amounts but increased total non-protein thiols. The above results indicated that Hg exerted its toxic effect on the root growth of alfalfa by induction of oxidative stress.


Assuntos
Medicago sativa/efeitos dos fármacos , Mercúrio/farmacologia , Estresse Oxidativo , Raízes de Plantas/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Peroxidação de Lipídeos , Medicago sativa/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
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