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1.
Cancer Causes Control ; 35(3): 417-427, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37812336

RESUMO

PURPOSE: While community engagement has been a longstanding aspect of cancer-relevant research in social and behavioral sciences, it is far less common in basic/translational/clinical research. With the National Cancer Institute's incorporation of Community Outreach and Engagement into the Cancer Center Support Grant guidelines, successful models are desirable. We report on a pilot study supported by the University of Maryland Greenebaum Comprehensive Cancer Center (UMGCCC), that used a community-engaged, data-driven process to inform a pre-clinical study of the impact of antioxidants on the efficacy of platinum-based chemotherapeutics. METHODS: We conducted a survey of UMGCCC catchment area residents (n = 120) to identify commonly used antioxidants. We then evaluated the effect of individually combining commonly used antioxidants from the survey (vitamin C, green tea, and melatonin) with platinum agents in models of non-small cell lung cancer (A549), colon adenocarcinoma (SW620) and head and neck squamous cell carcinoma (FaDu). RESULTS: In vitro, the anti-neoplastic activity of each chemotherapy was not potentiated by any of the antioxidants. Instead, when combined at fixed ratios, most antioxidant-chemotherapy combinations were antagonistic. In vivo, addition of antioxidants did not improve chemotherapeutic efficacy and in a FaDu-tumor bearing model, cisplatin-mediated tumor growth inhibition was significantly impeded by the addition of epigallocatechin gallate, the main antioxidant in green tea. CONCLUSION: These initial findings do not support addition of antioxidant supplementation to improve platinum-based chemotherapeutic efficacy. This study's approach can serve as a model of how to bring together the two seemingly discordant areas of basic research and community engagement.


Assuntos
Adenocarcinoma , Carcinoma Pulmonar de Células não Pequenas , Neoplasias do Colo , Neoplasias Pulmonares , Humanos , Antioxidantes/farmacologia , Projetos Piloto , Neoplasias do Colo/tratamento farmacológico , Chá
2.
Oral Dis ; 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36989132

RESUMO

OBJECTIVES: Gnathodiaphyseal dysplasia (GDD; OMIM#166260) is a rare skeletal genetic disorder characterized by sclerosis of tubular bones and cemento-osseous lesions in mandibles. TMEM16E/ANO5 gene mutations have been identified in patients with GDD. Here, Ano5 knockout (Ano5-/- ) mice with enhanced osteoblastogenesis were used to investigate whether Ano5 disruption affects osteoclastogenesis. SUBJECTS AND METHODS: The maturation of osteoclasts, formation of F-actin ring and bone resorption were detected by immunohistochemistry, TRAP, phalloidin staining and Coming Osteo assays. The expression of osteoclast-related factors was measured by qRT-PCR. Early signaling pathways were verified by western blot. RESULTS: Ano5-/- mice exhibited inhibitory formation of multinucleated osteoclasts with a reduction of TRAP activity. The expression of Nfatc1, c-Fos, Trap, Ctsk, Mmp9, Rank and Dc-stamp was significantly decreased in bone tissues and bone marrow-derived macrophages (BMMs) of Ano5-/- mice. Ano5-/- osteoclasts manifested disrupted actin ring and less mineral resorption. RANKL-induced early signaling pathways were suppressed in Ano5-/- osteoclasts and Ano5 knockdown RAW264.7 cells. Moreover, the inhibitory effects of NF-κB signalling pathway on osteoclastogenesis were partially attenuated with NF-κB signalling activator. CONCLUSIONS: Ano5 deficiency impairs osteoclastogenesis, which leads to enhanced osteogenic phenotypes mediated by bone homeostasis dysregulation.

3.
Proc Natl Acad Sci U S A ; 117(1): 761-770, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31871206

RESUMO

Small RNAs (sRNAs) associate with Argonaute (AGO) proteins in effector complexes, termed RNA-induced silencing complexes (RISCs), which regulate complementary transcripts by translation inhibition and/or RNA degradation. In the unicellular alga Chlamydomonas, several metazoans, and land plants, emerging evidence indicates that polyribosome-associated transcripts can be translationally repressed by RISCs without substantial messenger RNA (mRNA) destabilization. However, the mechanism of translation inhibition in a polyribosomal context is not understood. Here we show that Chlamydomonas VIG1, an ortholog of the Drosophila melanogaster Vasa intronic gene (VIG), is required for this process. VIG1 localizes predominantly in the cytosol and comigrates with monoribosomes and polyribosomes by sucrose density gradient sedimentation. A VIG1-deleted mutant shows hypersensitivity to the translation elongation inhibitor cycloheximide, suggesting that VIG1 may have a nonessential role in ribosome function/structure. Additionally, FLAG-tagged VIG1 copurifies with AGO3 and Dicer-like 3 (DCL3), consistent with it also being a component of the RISC. Indeed, VIG1 is necessary for the repression of sRNA-targeted transcripts at the translational level but is dispensable for cleavage-mediated RNA interference and for the association of the AGO3 effector with polyribosomes or target transcripts. Our results suggest that VIG1 is an ancillary ribosomal component and plays a role in sRNA-mediated translation repression of polyribosomal transcripts.


Assuntos
Chlamydomonas reinhardtii/fisiologia , Proteínas de Plantas/metabolismo , Biossíntese de Proteínas/fisiologia , RNA Interferente Pequeno/metabolismo , Complexo de Inativação Induzido por RNA/metabolismo , Proteínas Argonautas/metabolismo , Cicloeximida/farmacologia , Citosol/metabolismo , Regulação da Expressão Gênica de Plantas , Íntrons/genética , Mutação , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Polirribossomos/genética , Polirribossomos/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Ribossomos/efeitos dos fármacos , Ribossomos/metabolismo
4.
Int J Mol Sci ; 24(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37175747

RESUMO

OsMADS1 plays a vital role in regulating floret development and grain shape, but whether it regulates rice grain quality still remains largely unknown. Therefore, we used comprehensive molecular genetics, plant biotechnology, and functional omics approaches, including phenotyping, mapping-by-sequencing, target gene seed-specific RNAi, transgenic experiments, and transcriptomic profiling to answer this biological and molecular question. Here, we report the characterization of the 'Oat-like rice' mutant, with poor grain quality, including chalky endosperms, abnormal morphology and loose arrangement of starch granules, and lower starch content but higher protein content in grains. The poor grain quality of Oat-like rice was found to be caused by the mutated OsMADS1Olr allele through mapping-by-sequencing analysis and transgenic experiments. OsMADS1 protein is highly expressed in florets and developing seeds. Both OsMADS1-eGFP and OsMADS1Olr-eGFP fusion proteins are localized in the nucleus. Moreover, seed-specific RNAi of OsMADS1 also caused decreased grain quality in transgenic lines, such as the Oat-like rice. Further transcriptomic profiling between Oat-like rice and Nipponbare grains revealed that OsMADS1 regulates gene expressions and regulatory networks of starch and storage protein metabolisms in rice grains, hereafter regulating rice quality. In conclusion, our results not only reveal the crucial role and preliminary mechanism of OsMADS1 in regulating rice grain quality but also highlight the application potentials of OsMADS1 and the target gene seed-specific RNAi system in improving rice grain quality by molecular breeding.


Assuntos
Oryza , Amido , Amido/genética , Amido/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Endosperma/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas
5.
Zhongguo Zhong Yao Za Zhi ; 48(21): 5701-5706, 2023 Nov.
Artigo em Zh | MEDLINE | ID: mdl-38114166

RESUMO

The application of new-generation information technologies such as big data, the internet of things(IoT), and cloud computing in the traditional Chinese medicine(TCM)manufacturing industry is gradually deepening, driving the intelligent transformation and upgrading of the TCM industry. At the current stage, there are challenges in understanding the extraction process and its mechanisms in TCM. Online detection technology faces difficulties in making breakthroughs, and data throughout the entire production process is scattered, lacking valuable mining and utilization, which significantly hinders the intelligent upgrading of the TCM industry. Applying data-driven technologies in the process of TCM extraction can enhance the understanding of the extraction process, achieve precise control, and effectively improve the quality of TCM products. This article analyzed the technological bottlenecks in the production process of TCM extraction, summarized commonly used data-driven algorithms in the research and production control of extraction processes, and reviewed the progress in the application of data-driven technologies in the following five aspects: mechanism analysis of the extraction process, process development and optimization, online detection, process control, and production management. This article is expected to provide references for optimizing the extraction process and intelligent production of TCM.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Controle de Qualidade , Big Data , Algoritmos
6.
Plant Physiol ; 187(4): 2637-2655, 2021 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-34618092

RESUMO

Programmable site-specific nucleases, such as the clustered regularly interspaced short palindromic repeat (CRISPR)/ CRISPR-associated protein 9 (Cas9) ribonucleoproteins (RNPs), have allowed creation of valuable knockout mutations and targeted gene modifications in Chlamydomonas (Chlamydomonas reinhardtii). However, in walled strains, present methods for editing genes lacking a selectable phenotype involve co-transfection of RNPs and exogenous double-stranded DNA (dsDNA) encoding a selectable marker gene. Repair of the dsDNA breaks induced by the RNPs is usually accompanied by genomic insertion of exogenous dsDNA fragments, hindering the recovery of precise, scarless mutations in target genes of interest. Here, we tested whether co-targeting two genes by electroporation of pairs of CRISPR/Cas9 RNPs and single-stranded oligodeoxynucleotides (ssODNs) would facilitate the recovery of precise edits in a gene of interest (lacking a selectable phenotype) by selection for precise editing of another gene (creating a selectable marker)-in a process completely lacking exogenous dsDNA. We used PPX1 (encoding protoporphyrinogen IX oxidase) as the generated selectable marker, conferring resistance to oxyfluorfen, and identified precise edits in the homolog of bacterial ftsY or the WD and TetratriCopeptide repeats protein 1 genes in ∼1% of the oxyfluorfen resistant colonies. Analysis of the target site sequences in edited mutants suggested that ssODNs were used as templates for DNA synthesis during homology directed repair, a process prone to replicative errors. The Chlamydomonas acetolactate synthase gene could also be efficiently edited to serve as an alternative selectable marker. This transgene-free strategy may allow creation of individual strains containing precise mutations in multiple target genes, to study complex cellular processes, pathways, or structures.


Assuntos
Proteínas de Algas/genética , Sistemas CRISPR-Cas , Chlamydomonas/genética , Edição de Genes/métodos , Ribonucleoproteínas/genética
7.
Sensors (Basel) ; 22(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36015773

RESUMO

Because of the problem of low recognition accuracy in the recognition of intrusion vibration events by the distributed Sagnac type optical fiber sensing system, this paper combines the traditional optical fiber vibration signal recognition idea and the characteristics of automatic feature extraction by a convolutional neural network (CNN) to construct a new endpoint detection algorithm and a method of fusing multiple-scale features CNN to recognize fiber vibration signals. Firstly, a new endpoint detection algorithm combining spectral centroid and energy spectral entropy product is used to detect the vibration part of the original signal, which is used to improve the detection effect of endpoint detection. Then, CNNs of different scales are used to extract the multi-level and multi-scale features of the signal. Aiming at the problem of information loss in the pooling process, a new method of combining differential pooling features is used. Finally, a multi-layer perceptron (MLP) is used to recognize the extracted features. Experiments show that the method has an average recognition accuracy rate of 98.75% for the four types of vibration signals. Compared with traditional EMD and VMD pattern recognition and 1D-CNN methods, the accuracy of the optical fiber vibration signal recognition is higher.


Assuntos
Fibras Ópticas , Vibração , Algoritmos , Redes Neurais de Computação
8.
Sensors (Basel) ; 22(23)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36501965

RESUMO

In the traditional peripheral-security-early-warning system, the endpoint detection and pattern recognition of the signals generated by the distributed optical fiber vibration sensors is completed step-by-step and in an orderly manner. The method by which these two processes may be placed end-to-end in a network model and processed simultaneously to improve work efficiency has increasingly become the focus of research. In this paper, the target detection algorithm combines the endpoint-detection and pattern-recognition processes of the vibration signal, which can not only quickly locate the start and end vibration positions of the signal but also accurately identify a certain type of signal. You Only Look Once v4 (YOLOv4) is one of the most advanced target detection algorithms, achieving the optimal balance of speed and accuracy. To reduce the complexity of the YOLOv4 model and solve the dataset's unbalanced sample classification problem, we use a deep separable convolution (DSC) network and a focal loss function to improve the YOLOv4 model. In this paper, the five kinds of signals collected in real-time are visualized as two different datasets in oscillograph and time-frequency diagrams as detection objects. According to the experimental results, we obtained 98.50% and 93.48% mean Average Precision (mAP) and 84.8 and 69.9 frames per second (FPS), respectively, which are improved compared to YOLOv4. Comparing the improved algorithm with other optical fiber vibration signal recognition algorithms, the mAP and FPS values were improved, and the detection speed was about 20 times faster than that of other algorithms. The improved algorithm in this paper can quickly and accurately identify the vibration signal of external intrusion, reduce the false-alarm rate of the early-warning system, and improve the real-time detection rate of the system while ensuring high recognition accuracy.


Assuntos
Fibras Ópticas , Vibração , Modalidades de Fisioterapia , Oscilometria , Algoritmos
9.
Int J Mol Sci ; 23(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36499349

RESUMO

Salt-alkali stress threatens the resilience to variable environments and thus the grain yield of rice. However, how rice responds to salt-alkali stress at the molecular level is poorly understood. Here, we report isolation of a novel salt-alkali-tolerant rice (SATR) by screening more than 700 germplasm accessions. Using 93-11, a widely grown cultivar, as a control, we characterized SATR in response to strong salt-alkali stress (SSAS). SATR exhibited SSAS tolerance higher than 93-11, as indicated by a higher survival rate, associated with higher peroxidase activity and total soluble sugar content but lower malonaldehyde accumulation. A transcriptome study showed that cell wall biogenesis-related pathways were most significantly enriched in SATR relative to 93-11 upon SSAS. Furthermore, higher induction of gene expression in the cell wall matrix polysaccharide biosynthesis pathway, coupled with higher accumulations of hemicellulose and pectin as well as measurable physio-biochemical adaptive responses, may explain the strong SSAS tolerance in SATR. We mapped SSAS tolerance to five genomic regions in which 35 genes were candidates potentially governing SSAS tolerance. The 1,4-ß-D-xylan synthase gene OsCSLD4 in hemicellulose biosynthesis pathway was investigated in details. The OsCSLD4 function-disrupted mutant displayed reduced SSAS tolerance, biomass and grain yield, whereas the OsCSLD4 overexpression lines exhibited increased SSAS tolerance. Collectively, this study not only reveals the potential role of cell wall matrix polysaccharides in mediating SSAS tolerance, but also highlights applicable value of OsCSLD4 and the large-scale screening system in developing SSAS-tolerant rice.


Assuntos
Oryza , Oryza/metabolismo , Álcalis/metabolismo , Tolerância ao Sal/genética , Parede Celular/metabolismo , Polissacarídeos/metabolismo , Cloreto de Sódio/metabolismo
10.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806336

RESUMO

1',4'-trans-diol-ABA is a key precursor of the biosynthesis of abscisic acid (ABA) biosynthesis in fungi. We successfully obtained the pure compound from a mutant of Botrytis cinerea and explored its function and possible mechanism on plants by spraying 2 mg/L 1',4'-trans-diol-ABA on tobacco leaves. Our results showed that this compound enhanced the drought tolerance of tobacco seedlings. A comparative transcriptome analysis showed that a large number of genes responded to the compound, exhibiting 1523 genes that were differentially expressed at 12 h, which increased to 1993 at 24 h and 3074 at 48 h, respectively. The enrichment analysis demonstrated that the differentially expressed genes (DEGs) were primarily enriched in pathways related to hormones and resistance. The DEGs of transcription factors were generally up-regulated and included the bHLH, bZIP, ERF, MYB, NAC, WRKY and HSF families. Moreover, the levels of expression of PYL/PYR, PP2C, SnRK2, and ABF at the ABA signaling pathway responded positively to exogenous 1',4'-trans-diol-ABA. Among them, seven ABF transcripts that were detected were significantly up-regulated. In addition, the genes involved in salicylic acid, ethylene and jasmonic acid pathways, reactive oxygen species scavenging system, and other resistance related genes were primarily induced by 1',4'-trans-diol-ABA. These findings indicated that treatment with 1',4'-trans-diol-ABA could improve tolerance to plant abiotic stress and potential biotic resistance by regulating gene expression, similar to the effects of exogenous ABA.


Assuntos
Ácido Abscísico/análogos & derivados , Nicotiana/efeitos dos fármacos , Nicotiana/genética , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Ácido Abscísico/farmacologia , Botrytis/química , Secas , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ontologia Genética , Redes Reguladoras de Genes , Genes de Plantas , Modelos Biológicos , Reguladores de Crescimento de Plantas/genética , Proteínas de Plantas/genética , Estômatos de Plantas/anatomia & histologia , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Nicotiana/fisiologia , Fatores de Transcrição/genética
11.
BMC Plant Biol ; 20(1): 320, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32635887

RESUMO

BACKGROUND: The non-coding small RNA tRFs (tRNA-derived fragments) and phasiRNAs (plant-specific) exert important roles in plant growth, development and stress resistances. However, whether the tRFs and phasiRNAs respond to the plant important stress hormone abscisic acid (ABA) remain enigma. RESULTS: Here, the RNA-sequencing was implemented to decipher the landscape of tRFs and phasiRNAs in tomato (Solanum lycopersicum) leaves and their responses when foliar spraying exogenous ABA after 24 h. In total, 733 tRFs and 137 phasiRNAs were detected. The tRFs were mainly derived from the tRNAAla transporting alanine, which tended to be cleaved at the 5'terminal guanine site and D loop uracil site to produce tRFAla with length of 20 nt. Most of phasiRNAs originated from NBS-LRR resistance genes. Expression analysis revealed that 156 tRFs and 68 phasiRNAs expressed differentially, respectively. Generally, exogenous ABA mainly inhibited the expression of tRFs and phasiRNAs. Furthermore, integrating analysis of target gene prediction and transcriptome data presented that ABA significantly downregulated the abundance of phsaiRNAs associated with biological and abiotic resistances. Correspondingly, their target genes such as AP2/ERF, WRKY and NBS-LRR, STK and RLK, were mainly up-regulated. CONCLUSIONS: Combined with the previous analysis of ABA-response miRNAs, it was speculated that ABA can improve the plant resistances to various stresses by regulating the expression and interaction of small RNAs (such as miRNAs, tRFs, phasiRNAs) and their target genes. This study enriches the plant tRFs and phasiRNAs, providing a vital basis for further investigating ABA response-tRFs and phasiRNAs and their functions in biotic and abiotic stresses.


Assuntos
Ácido Abscísico/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , RNA de Plantas/efeitos dos fármacos , Solanum lycopersicum/genética , Transcriptoma/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/fisiologia , MicroRNAs/efeitos dos fármacos , MicroRNAs/genética , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/fisiologia , RNA de Plantas/genética , Pequeno RNA não Traduzido/efeitos dos fármacos , Pequeno RNA não Traduzido/genética , RNA de Transferência/genética , Análise de Sequência de RNA , Estresse Fisiológico/genética
13.
Microb Ecol ; 77(4): 967-979, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30357425

RESUMO

Titanium ions significantly promote plant growth, but the mechanism is still unclear. Cut flowers are ideal materials for the study of plant growth and senescence. In this study, freshly cut Gerbera jamesonii were used to study the effects of titanium ions (8 mg/L) on the flower longevity. Flowering observation showed that the gerbera vase life was significantly prolonged in the presence of titanium ions. Plate colony counts showed that the amounts of bacteria in the vase solution of the control group were approximately 1700 times more than that of titanium ion treatment group. High-throughput sequencing was used to determine the sequences of 16S rRNA gene V3-V4 variable regions of the vase solutions to analyze bacterial species, their average proportions, and absolute abundance. The results showed that the titanium ions reduced the entire bacterial counts as well as altered the absolute abundance of different bacterial species in the vase solution. The most prevalent bacteria were mainly Enterobacteriaceae, Pseudomonas veronii, Pseudomonas sp., Delftia sp., Agrobacterium sp., Sphingobacterium multivorum, Acinetobacter johnsonii, and Clostridiaceae. In combination with plate colony counts, we demonstrated that all the bacterial growths were significantly inhibited by titanium ions, regardless of their average proportions increased or decreased. These results showed that titanium ions could extend effectively the longevity of gerberas and possess the broad-spectrum antibacterial properties. This study provides a basis for further mechanism exploration of titanium ions action and its applications in cut flower preservation and agricultural production.


Assuntos
Bactérias/metabolismo , Titânio/metabolismo , Microbiologia da Água , Asteraceae/crescimento & desenvolvimento , Bactérias/classificação , Bactérias/efeitos dos fármacos , Flores/crescimento & desenvolvimento , Íons/metabolismo , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
14.
Plant Mol Biol ; 98(4-5): 319-331, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30298427

RESUMO

The Lemnaceae, known as duckweed, the smallest flowering aquatic plant, shows promise as a plant bioreactor. For applying this potential plant bioreactor, establishing a stable and efficient genetic transformation system is necessary. The currently favored callus-based method for duckweed transformation is time consuming and genotype limited, as it requires callus culture and regeneration, which is inapplicable to many elite duckweed strains suitable for bioreactor exploitation. In this study, we attempted to establish a simple frond transformation system mediated by Agrobacterium tumefaciens for Lemna minor, one of the most widespread duckweed species in the world. To evaluate the feasibility of the new transformation system, the gene CYP710A11 was overexpressed to improve the yield of stigmasterol, which has multiple medicinal purposes. Three L. minor strains, ZH0055, D0158 and M0165, were transformed by both a conventional callus transformation system (CTS) and the simple frond transformation system (FTS). GUS staining, PCR, quantitative PCR and stigmasterol content detection showed that FTS can produce stable transgenic lines as well as CTS. Moreover, compared to CTS, FTS can avoid the genotype constraints of callus induction, thus saving at least half of the required processing time (CTS took 8-9 months while FTS took approximately 3 months in this study). Therefore, this transformation system is feasible in producing stable transgenic lines for a wide range of L. minor genotypes.


Assuntos
Agrobacterium tumefaciens/genética , Alismatales/genética , Engenharia Genética/métodos , Alismatales/metabolismo , Reatores Biológicos , Sistema Enzimático do Citocromo P-450/genética , Vetores Genéticos/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Reação em Cadeia da Polimerase , Estigmasterol/metabolismo , Transformação Genética/genética
15.
BMC Genomics ; 18(1): 166, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28201992

RESUMO

BACKGROUND: As the fastest growing plant, duckweed can thrive on anthropogenic wastewater. The purple-backed duckweed, Landoltia punctata, is rich in starch and flavonoids. However, the molecular biological basis of high flavonoid and low lignin content remains largely unknown, as does the best method to combine nutrients removed from sewage and the utilization value improvement of duckweed biomass. RESULTS: A combined omics study was performed to investigate the biosynthesis of flavonoid and the metabolic flux changes in L. punctata grown in different culture medium. Phenylalanine metabolism related transcripts were identified and carefully analyzed. Expression quantification results showed that most of the flavonoid biosynthetic transcripts were relatively highly expressed, while most lignin-related transcripts were poorly expressed or failed to be detected by iTRAQ based proteomic analyses. This explains why duckweed has a much lower lignin percentage and higher flavonoid content than most other plants. Growing in distilled water, expression of most flavonoid-related transcripts were increased, while most were decreased in uniconazole treated L. punctata (1/6 × Hoagland + 800 mg•L-1 uniconazole). When L. punctata was cultivated in full nutrient medium (1/6 × Hoagland), more than half of these transcripts were increased, however others were suppressed. Metabolome results showed that a total of 20 flavonoid compounds were separated by HPLC in L. punctata grown in uniconazole and full nutrient medium. The quantities of all 20 compounds were decreased by uniconazole, while 11 were increased and 6 decreased when grown in full nutrient medium. Nutrient starvation resulted in an obvious purple accumulation on the underside of each frond. CONCLUSIONS: The high flavonoid and low lignin content of L. punctata appears to be predominantly caused by the flavonoid-directed metabolic flux. Nutrient starvation is the best option to obtain high starch and flavonoid accumulation simultaneously in a short time for biofuels fermentation and natural products isolation.


Assuntos
Araceae/metabolismo , Flavonoides/metabolismo , Amido/metabolismo , Araceae/genética , Regulação da Expressão Gênica de Plantas , Lignina/biossíntese , Fenilalanina/biossíntese , Proteômica , Análise de Sequência de RNA
16.
BMC Genomics ; 17: 423, 2016 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-27260799

RESUMO

BACKGROUND: Plant microRNAs (miRNAs) are involved in various biological pathways and stress responses as negative regulators at the posttranscriptional level. Abscisic acid (ABA) is a key signaling molecule that mediates plant stress response by activating many stress-related genes. Although some miRNAs in plants are previously identified to respond to ABA, a comprehensive profile of ABA-responsive miRNAs has not yet been elucidated. RESULTS: Here, we identified miRNAs responding to exogenous application of ABA, and their predicted target genes in the model plant organism tomato (Solanum lycopersicum). Deep sequencing of small RNAs from ABA-treated and untreated tomatoes revealed that miRNAs can be up- or down-regulated upon treatment with ABA. A total of 1067 miRNAs were detected (including 365 known and 702 candidate novel miRNAs), of those, 416 miRNAs which had an abundance over two TPM (transcripts per million) were selected for differential expression analysis. We identified 269 (180 known and 89 novel) miRNAs that respond to exogenous ABA treatment with a change in expression level of |log2FC|≥0.25. 136 of these miRNAs (90 known and 46 novel) were expressed at significantly different levels |log2FC|≥1 between treatments. Furthermore, stem-loop RT-PCR was applied to validate the RNA-seq data. Target prediction and analysis of the corresponding ABA-responsive transcriptome data uncovered that differentially expressed miRNAs are involved in condition stress and pathogen resistance, growth and development. Among them, approximately 90 miRNAs were predicted to target transcription factors and pathogen resistance genes. Some miRNAs had functional overlap in biotic and abiotic stress. Most of these miRNAs were down-regulated following exposure to exogenous ABA, while their related target genes were inversely up-regulated, which is consistent with their negative regulatory role in gene expression. CONCLUSIONS: Exogenous ABA application influences the composition and expression level of tomato miRNAs. ABA mainly down-regulates miRNAs that their target genes involve in abiotic stress adaption and disease resistance. ABA might increase expression of stress-related genes via miRNA-mediated posttranscriptional regulation, and our results indicate that ABA treatment has the potential to improve both abiotic stress tolerance and pathogen resistance. This study presents a comprehensive profile of ABA-regulated miRNAs in the tomato, and provides a robust database for further investigation of ABA regulatory mechanisms.


Assuntos
Ácido Abscísico/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genoma de Planta , Genômica , MicroRNAs/genética , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/genética , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Interferência de RNA , RNA Mensageiro/genética , Reprodutibilidade dos Testes , Transcriptoma
17.
Plant Cell ; 25(3): 985-98, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23512853

RESUMO

Small RNAs (sRNAs; ∼20 to 30 nucleotides in length) play important roles in gene regulation as well as in defense responses against transposons and viruses in eukaryotes. Their biogenesis and modes of action have attracted great attention in recent years. However, many aspects of sRNA function, such as the mechanism(s) of translation repression at postinitiation steps, remain poorly characterized. In the unicellular green alga Chlamydomonas reinhardtii, sRNAs derived from genome-integrated inverted repeat transgenes, perfectly complementary to the 3' untranslated region of a target transcript, can inhibit protein synthesis without or with only minimal mRNA destabilization. Here, we report that the sRNA-repressed transcripts are not altered in their polyadenylation status and they remain associated with polyribosomes, indicating inhibition at a postinitiation step of translation. Interestingly, ribosomes associated with sRNA-repressed transcripts show reduced sensitivity to translation inhibition by some antibiotics, such as cycloheximide, both in ribosome run-off assays and in in vivo experiments. Our results suggest that sRNA-mediated repression of protein synthesis in C. reinhardtii may involve alterations to the function/structural conformation of translating ribosomes. Additionally, sRNA-mediated translation inhibition is now known to occur in a number of phylogenetically diverse eukaryotes, suggesting that this mechanism may have been a feature of an ancestral RNA interference machinery.


Assuntos
Chlamydomonas reinhardtii/efeitos dos fármacos , Cicloeximida/farmacologia , Polirribossomos/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , RNA de Plantas/metabolismo , RNA Interferente Pequeno/metabolismo , Chlamydomonas reinhardtii/classificação , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo , Meios de Cultura/metabolismo , Genes de Plantas , Higromicina B/farmacologia , Organismos Geneticamente Modificados/genética , Organismos Geneticamente Modificados/metabolismo , Filogenia , Polirribossomos/genética , Polirribossomos/metabolismo , Estabilidade de RNA , RNA de Plantas/genética , RNA Interferente Pequeno/genética , Relação Estrutura-Atividade
18.
Int J Clin Pharmacol Ther ; 54(1): 36-42, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26521927

RESUMO

OBJECTIVE: In China, maintenance treatment for clinically stable patients with schizophrenia is usually provided by primary care physicians, but their prescribing patterns have not been studied. This study examined the frequency as well as demographic and clinical correlates of antipsychotic polypharmacy (APP) and its impact on quality of life (QOL) in patients with schizophrenia treated in primary care in China. METHOD: A total of 623 community-dwelling patients from 18 randomly selected primary care services were interviewed. Patients' socio-demographic and clinical characteristics, including number of hospitalizations, antipsychotic drug-induced side effects, and QOL were recorded using a standardized protocol and data collection procedure. RESULTS: The rate of APP prescription was 31% (193/623). Of the patients on APP, 89.6% received 2 antipsychotics, 10.4% received 3 or more antipsychotics. Clozapine (35.6%) was the most commonly prescribed second generation antipsychotic (SGA), while perphenazine (17.8%) was the most commonly prescribed first generation antipsychotic (FGA). Multiple logistic regression analyses revealed that patients on APP were more likely to receive SGAs and anticholinergics, had fewer hospitalizations, younger age of onset, and higher doses of antipsychotics. There were no significant differences between the two groups in any of the QOL domains. CONCLUSIONS: Approximately a third of Chinese patients with schizophrenia in primary care receive APP. Further examination of the rationale and appropriateness of APP and its alternatives is warranted.


Assuntos
Antipsicóticos/uso terapêutico , Polimedicação , Atenção Primária à Saúde , Qualidade de Vida , Esquizofrenia/tratamento farmacológico , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Community Ment Health J ; 52(8): 921-926, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27306990

RESUMO

This study described the prevalence and correlates of comorbid moderate-severe depressive symptoms (comorbid depression thereafter) and their association with quality of life (QOL) in schizophrenia patients treated in primary care. 623 schizophrenia patients were enrolled. Patients' socio-demographic and clinical characteristics including comorbid depression [defined as a total score of 18 or above on the Montgomery-Asberg Depression Rating Scale (MADRS)] were recorded. Depressive symptoms (defined as a total score of 9 or above on the MADRS) were present in 54.1 % of patients, while 17.7 % had comorbid depression. Analysis of covariance revealed that comorbid depression was significantly associated with lower mental QOL. Multiple logistic regression analysis revealed that more severe positive and negative symptoms, anxiety symptoms, use of first-generation antipsychotics and antidepressants, were independently associated with comorbid depression. Given the negative association between comorbid depression and QOL, attempts to address comorbid depression in schizophrenia patients treated in primary care should be made.


Assuntos
Povo Asiático/psicologia , Comorbidade , Transtorno Depressivo/epidemiologia , Atenção Primária à Saúde , Qualidade de Vida , Esquizofrenia/epidemiologia , Adulto , Antidepressivos/uso terapêutico , Antipsicóticos/uso terapêutico , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
20.
BMC Biotechnol ; 15: 81, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26369558

RESUMO

BACKGROUND: Duckweed (Landoltia punctata) has the potential to remediate wastewater and accumulate enormous amounts of starch for bioethanol production. Using systematical screening, we determined that the highest biomass and starch percentage of duckweed was obtained after uniconazole application. Uniconazole contributes to starch accumulation of duckweed, but the molecular mechanism is still unclear. RESULTS: To elucidate the mechanisms of high starch accumulation, in the study, the responses of L. punctata to uniconazole were investigated using a quantitative proteomic approach combined with physiological and biochemical analysis. A total of 3327 proteins were identified. Among these identified proteins, a large number of enzymes involved in endogenous hormone synthetic and starch metabolic pathways were affected. Notably, most of the enzymes involved in abscisic acid (ABA) biosynthesis showed up-regulated expression, which was consistent with the content variation. The increased endogenous ABA may up-regulate expression of ADP-glucose pyrophosphorylase to promote starch biosynthesis. Importantly, the expression levels of several key enzymes in the starch biosynthetic pathway were up-regulated, which supported the enzymatic assay results and may explain why there is increased starch accumulation. CONCLUSIONS: These generated data linked uniconazole with changes in expression of enzymes involved in hormone biosynthesis and starch metabolic pathways and elucidated the effect of hormones on starch accumulation. Thus, this study not only provided insights into the molecular mechanisms of uniconazole-induced hormone variation and starch accumulation but also highlighted the potential for duckweed to be feedstock for biofuel as well as for sewage treatment.


Assuntos
Araceae/efeitos dos fármacos , Reguladores de Crescimento de Plantas/análise , Proteínas de Plantas/análise , Amido/análise , Triazóis/farmacologia , Araceae/enzimologia , Araceae/metabolismo , Cromatografia Líquida , Marcação por Isótopo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/análise , Proteoma/metabolismo , Proteômica , Amido/metabolismo , Espectrometria de Massas em Tandem
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