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1.
Food Funct ; 12(20): 9719-9738, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34664590

RESUMO

Obesity is a global chronic disease epidemic that is attributed to the abnormal accumulation of lipids in adipose tissue. Astaxanthin (AST) from Haematococcus pluvialis, a natural carotenoid, exhibits antioxidant, anti-lipogenic, anti-diabetic and other potent effects. Herein, we evaluated the effect of AST to illuminate its efficacy and mechanisms in high-fat diet-fed mice. AST supplementation not only significantly decreased body weight and lipid droplet accumulation in the liver but also modulated liver function and serum lipid levels. Lipidomic analysis revealed that 13 lipids might be potential biomarkers responsible for the effects of AST in lipid reduction, such as total free fatty acids (FFAs), triacylglycerols (TGs) and cholesterol esters (CEs). The gut microbiota sequencing results indicated that AST alleviated HFD-induced gut microbiota dysbiosis by optimizing the ratio of Firmicutes to Bacteroides and inhibiting the abundance of obesity-related pathogenic microbiota while promoting the abundance of probiotics related to glucose and lipid metabolism. In addition, qRT-PCR demonstrated that AST could regulate the gene expressions of the AMPK/SREBP1c pathway by downregulating lipogenesis correlated-genes and upregulating the lipid oxidant related-gene. The present study revealed the new function of AST in regulating lipid metabolism, which provided a theoretical basis for the development of high-quality AST functional food and the application of diet active substances in obesity, as demonstrated in mice.

2.
Sheng Wu Gong Cheng Xue Bao ; 37(8): 2845-2855, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34472302

RESUMO

Production of biofuels such as ethanol from non-grain crops may contribute to alleviating the global energy crisis and reducing the potential threat to food security. Tobacco (Nicotiana tabacum) is a commercial crop with high biomass yield. Breeding of starch-rich tobacco plants may provide alternative raw materials for the production of fuel ethanol. We cloned the small subunit gene NtSSU of ADP-glucose pyrophosphorylase (NtAGPase), which controls starch biosynthesis in tobacco, and constructed a plant expression vector pCAMBIA1303-NtSSU. The NtSSU gene was overexpressed in tobacco upon Agrobacterium-mediated leaf disc transformation. Phenotypic analysis showed that overexpression of NtSSU gene promoted the accumulation of starch in tobacco leaves, and the content of starch in tobacco leaves increased from 17.5% to 41.7%. The growth rate and biomass yield of the transgenic tobacco with NtSSU gene were also significantly increased. The results revealed that overexpression of NtSSU gene could effectively redirect more photosynthesis carbon flux into starch biosynthesis pathway, which led to an increased biomass yield but did not generate negative effects on other agronomic traits. Therefore, NtSSU gene can be used as an excellent target gene in plant breeding to enrich starch accumulation in vegetative organs to develop new germplasm dedicated to fuel ethanol production.


Assuntos
Amido , Tabaco , Biomassa , Regulação da Expressão Gênica de Plantas , Melhoramento Vegetal , Folhas de Planta/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tabaco/genética , Tabaco/metabolismo
3.
J Environ Manage ; 298: 113543, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392095

RESUMO

Algae based wastewater treatment has been considered as the most promising win-win strategy for nutrients removal and biomass accumulation. However, the poor linking between traditional wastewater treatment and algal cultivation limits the achievement of this goal. In this study, a novel combination of Fenton oxidation and algal cultivation (CFOAC) system was investigated for the treatment of chicken farm flushing wastewater (CFFW). Fenton oxidation (FO) was adopted to reduce the excessive ammonia nitrogen, which might inhibit the algal growth. The results showed that single FO pretreatment removed 70.5 %, 96.7 %, 86.1 %, and 96.2 % of TN, TAN, TP, and COD, respectively. The highest biomass (235.8 mg/L/d) and lipid (77.3 mg/L/d) productivities were achieved on optimized CFOAC system after 7 days batch cultivation. Accordingly, the nutrients removal efficiencies increased to almost 100 %. Further fatty acid profile analysis showed that algae grown on optimal CFOAC system accumulated a high level of total lipids (32.8 %) with C16-C18 fatty acid as the most abundant compositions (accounting for over 60.6 %), which were propitious to biodiesel production. In addition, this CFOAC system was magnified from 1 L flask to 50 L horizontal pipe photobioreactor (HPPB) in semi-continuously culture under optimal conditions. The average biomass and lipid productivities were 995.7 mg/L/d and 320.6 mg/L/d, respectively, when cultured at 6 days hydraulic retention time with 1/3 substitution every two days. These findings proved that the novel CFOAC system is efficient in nutrients removal, algal cultivation, and biomass production for advanced treatment of CFFW.


Assuntos
Microalgas , Águas Residuárias , Animais , Biocombustíveis , Biomassa , Galinhas , Fazendas , Nitrogênio/análise , Nutrientes
4.
J Environ Manage ; 297: 113273, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311253

RESUMO

A palmitoleic acid-rich Scenedesmus obliquus strain SXND-02 was isolated from ammonium-containing wastewater. Biomass and lipid production were examined for this microalgal strain in photoautotrophic, heterotrophic, and mixotrophic cultivations, respectively, in order to extend its application in wastewater purification coupled with production of valued bio-products. Among the tested conditions, the microalga had better growth and higher lipid accumulation in mixotrophy. NH4Cl inhibited the microalgal growth in photoautotrophic cultivation. However, NaAc alleviated this inhibition in both heterotrophy and mixotrophy. Using 7 g L-1 NaAc and 0.5 g L-1 NH4Cl as carbon and nitrogen sources significantly increased the algal biomass and lipid yields under mixotrophic cultivation, with the highest levels up to 1.0 g L-1 and 59.88%, respectively. Fatty acid profiling indicated that palmitoleic acid was 23% in the S. obliquus SXND-02 under mixotrophic condition, which was about 21-fold higher than that in the control S. obliquus. Furthermore, this microalgal strain was tested in the chicken farm wastewater (CFW) containing high ammonium. Compared with other treatments, the S. obliquus SXND-02 cultivated in the 1/2 CFW + NaAc medium produced larger amounts of biomass (2.18 g L-1) and lipids (50.22%), and simultaneously higher removal rates of total nitrogen (TN) (80%), total ammonium nitrogen (TAN) (68%), total phosphate (TP) (82%), biological oxygen demand (BOD) (86%) and chemical oxygen demand (COD) (89%) from wastewater. The present data indicate that this excellent microalga can be used in mixotrophic cultivation for wastewater purification coupled with commercial production of valued biomass and high-quality algal oils.


Assuntos
Compostos de Amônio , Microalgas , Scenedesmus , Purificação da Água , Acetatos , Biocombustíveis , Biomassa , Ácidos Graxos Monoinsaturados , Óleos , Águas Residuárias
5.
Biomed Res Int ; 2021: 5585206, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34124248

RESUMO

Background: We aimed to examine the differences of clinical characteristics between patients with ischemic stroke with active cancer and those without cancer to develop a clinical score for predicting the presence of occult cancer in patients with ischemic stroke. Methods: This retrospective study enrolled consecutive adult patients with acute ischemic stroke who were admitted to our department between December 2017 and January 2019. The demographic, clinical, laboratory, and neuroimaging characteristics were compared between patients with ischemic stroke with active cancer and those without cancer. Multivariate analysis was performed to identify independent factors associated with active cancer. Subsequently, a predictive score was developed using the areas under the receiver operating characteristic curves based on these independent factors. Finally, Bayesian decision theory was applied to calculate the posterior probability of active cancer for finding the best scoring system. Results: Fifty-three (6.63%) of 799 patients with ischemic stroke had active cancer. The absence of a history of hyperlipidemia (odds ratio (OR) = 0.17, 95% confidence interval (CI): 0.06-0.48, P < 0.01), elevated serum fibrinogen (OR = 1.72, 95% CI: 1.33-2.22, P < 0.01) and D-dimer levels (OR = 1.43, 95% CI: 1.24-1.64, P <0.01), and stroke of undetermined etiology (OR = 22.87, 95% CI: 9.91-52.78, P < 0.01) were independently associated with active cancer. A clinical score based on the absence of hyperlipidemia, serum fibrinogen level of ≥4.00 g/L, and D-dimer level of ≥2.00 µg/mL predicted active cancer with an area under the curve of 0.83 (95% CI: 0.77-0.89, P < 0.01). The probability of active cancer was 59% at a supposed prevalence of 6.63%, if all three independent factors were present in a patient with ischemic stroke. Conclusions: We devised a clinical score to predict active cancer in patients with ischemic stroke based on the absence of a history of hyperlipidemia and elevated serum D-dimer and fibrinogen levels. The use of this score may allow for early intervention. Further research is needed to confirm the implementation of this score in clinical settings.


Assuntos
Biomarcadores Tumorais/sangue , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , AVC Isquêmico , Neoplasias , Idoso , Feminino , Humanos , AVC Isquêmico/sangue , AVC Isquêmico/diagnóstico , AVC Isquêmico/etiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/complicações , Neoplasias/diagnóstico , Estudos Retrospectivos
6.
Sheng Wu Gong Cheng Xue Bao ; 37(4): 1260-1276, 2021 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-33973440

RESUMO

The unicellular green alga Haematococcus pluvialis is the best source of natural astaxanthin (AST) in the world due to its high content under stress conditions. Although high light (HL) can effectively induce AST biosynthesis, the specific mechanisms of light signal perception and transduction are unclear. In the current study, we used transcriptomic data of normal (N), high white light (W), and high blue light (B) to study the mechanisms of light inducing AST accumulation from the point of photoreceptors. The original data of 4.0 G, 3.8 G, and 3.6 G for N, W, and B were obtained, respectively, by the Illumina Hi-seq 2000 sequencing technology. Totally, 51 954 unigenes (at least 200 bp in length) were generated, of which, 20 537 unigenes were annotated into at least one database (NR, NT, KO, SwissProt, Pfam, GO, or KOG). There were 1 255 DEGs in the W vs N, 1 494 DEGs in the B vs N, and 1 008 DEGs in the both W vs N and B vs N. KEGG enrichment analysis revealed that photosynthesis, oxidative phosphorylation, carotenoid biosynthesis, fatty acids biosynthesis, DNA replication, nitrogen metabolism, and carbon metabolism were the significantly enriched pathways. Moreover, a large number of genes encoding photoreceptors and predicted interacting proteins were predicted in Haematococcus transcriptome data. These genes showed significant differences at transcriptional expression levels. In addition, 15 related DEGs were selected and tested by qRT-PCR and the results were significantly correlated with the transcriptome data. The above results indicate that the signal transduction pathway of "light signal - photoreceptors - interaction proteins - (interaction proteins - transcription factor/transcriptional regulator) - gene expression - AST accumulation" might play important roles in the regulation process, and provide reference for further understanding the transcriptional regulation mechanisms of AST accumulation under HL stress.


Assuntos
Clorófitas , Clorófitas/genética , Perfilação da Expressão Gênica , Transdução de Sinais/genética , Transcriptoma/genética , Xantofilas
7.
BMC Plant Biol ; 21(1): 20, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407140

RESUMO

BACKGROUND: Haematococcus lacustris is an ideal source of astaxanthin (AST), which is stored in oil bodies containing esterified AST (EAST) and triacylglycerol (TAG). Diacylglycerol acyltransferases (DGATs) catalyze the last step of acyl-CoA-dependent TAG biosynthesis and are also considered as crucial enzymes involved in EAST biosynthesis in H. lacustris. Previous studies have identified four putative DGAT2-encoding genes in H. lacustris, and only HpDGAT2D allowed the recovery of TAG biosynthesis, but the engineering potential of HpDGAT2s in TAG biosynthesis remains ambiguous. RESULTS: Five putative DGAT2 genes (HpDGAT2A, HpDGAT2B, HpDGAT2C, HpDGAT2D, and HpDGAT2E) were identified in H. lacustris. Transcription analysis showed that the expression levels of the HpDGAT2A, HpDGAT2D, and HpDGAT2E genes markedly increased under high light and nitrogen deficient conditions with distinct patterns, which led to significant TAG and EAST accumulation. Functional complementation demonstrated that HpDGAT2A, HpDGAT2B, HpDGAT2D, and HpDGAT2E had the capacity to restore TAG synthesis in a TAG-deficient yeast strain (H1246) showing a large difference in enzymatic activity. Fatty acid (FA) profile assays revealed that HpDGAT2A, HpDGAT2D, and HpDGAT2E, but not HpDGAT2B, preferred monounsaturated fatty acyl-CoAs (MUFAs) for TAG synthesis in yeast cells, and showed a preference for polyunsaturated fatty acyl-CoAs (PUFAs) based on their feeding strategy. The heterologous expression of HpDGAT2D in Arabidopsis thaliana and Chlamydomonas reinhardtii significantly increased the TAG content and obviously promoted the MUFAs and PUFAs contents. CONCLUSIONS: Our study represents systematic work on the characterization of HpDGAT2s by integrating expression patterns, AST/TAG accumulation, functional complementation, and heterologous expression in yeast, plants, and algae. These results (1) update the gene models of HpDGAT2s, (2) prove the TAG biosynthesis capacity of HpDGAT2s, (3) show the strong preference for MUFAs and PUFAs, and (4) offer target genes to modulate TAG biosynthesis by using genetic engineering methods.


Assuntos
Clorofíceas/enzimologia , Clorofíceas/genética , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Genes de Plantas , Triglicerídeos/biossíntese , Triglicerídeos/genética , Regulação da Expressão Gênica de Plantas
8.
Plant Sci ; 303: 110752, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33487340

RESUMO

Diacylglycerol acyltransferases (DGAT) catalyze the final committed step of de novo biosynthesis of triacylglycerol (TAG) in plant seeds. This study was to functionally characterize DGAT3 genes in Camelina sativa, an important oil crops accumulating high levels of unsaturated fatty acids (UFAs) in seeds. Three camelina DGAT3 genes (CsDGAT3-1, CsDGAT3-2 and CsDGAT3-3) were identified, and the encoded proteins were predicted to be cytosolic-soluble proteins present as a homodimer containing the 2Fe-2S domain. They had divergent expression patterns in various tissues, suggesting that they may function in tissue-specific manner with CsDGAT3-1 in roots, CsDGAT3-2 in flowers and young seedlings, and CsDGAT3-3 in developing seeds. Functional complementation assay in yeast demonstrated that CsDGAT3-3 restored TAG synthesis. TAG content and UFAs, particularly eicosenoic acid (EA, 20:1n-9) were largely increased by adding exogenous UFAs in the yeast medium. Further heterogeneously transient expression in N. benthamiana leaves and seed-specific expression in tobacco seeds indicated that CsDGAT3-3 significantly enhanced oil and UFA accumulation with much higher level of EA. Overall, CsDGAT3-3 exhibited a strong abilty catalyzing TAG synthesis and high substrate preference for UFAs, especially for 20:1n-9. The present data provide new insights for further understanding oil biosynthesis mechanism in camelina seeds, indicating that CsDGAT3-3 may have practical applications for increasing both oil yield and quality.


Assuntos
Acil Coenzima A/metabolismo , Aciltransferases/genética , Camellia/genética , Genes de Plantas/genética , Proteínas de Plantas/genética , Aciltransferases/metabolismo , Aciltransferases/fisiologia , Camellia/enzimologia , Camellia/fisiologia , Clonagem Molecular , Ácidos Graxos Monoinsaturados/metabolismo , Genes de Plantas/fisiologia , Organismos Geneticamente Modificados , Proteínas de Plantas/metabolismo , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas , Saccharomyces cerevisiae , Análise de Sequência de DNA , Especificidade por Substrato , Tabaco , Transcriptoma
9.
BMC Genomics ; 21(1): 786, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33176698

RESUMO

BACKGROUND: WRKY transcription factors are a superfamily of regulators involved in diverse biological processes and stress responses in plants. However, there is limited knowledge about the WRKY family in camelina (Camelina sativa), an important Brassicaceae oil crop with strong tolerance for various stresses. Here, a genome-wide characterization of WRKY proteins is performed to examine their gene structures, phylogenetics, expression, conserved motif organizations, and functional annotation to identify candidate WRKYs that mediate stress resistance regulation in camelinas. RESULTS: A total of 242 CsWRKY proteins encoded by 224 gene loci distributed unevenly over the chromosomes were identified, and they were classified into three groups by phylogenetic analysis according to their WRKY domains and zinc finger motifs. The 15 CsWRKY gene loci generated 33 spliced variants. Orthologous WRKY gene pairs were identified, with 173 pairs in the C. sativa and Arabidopsis genomes as well as 282 pairs in the C. sativa and B. napus genomes, respectively. A total of 137 segmental duplication events were observed, but there was no tandem duplication in the camelina genome. Ten major conserved motifs were examined, with WRKYGQK being the most conserved, and several variants were present in many CsWRKYs. Expression analysis revealed that 50% more CsWRKY genes were expressed constitutively, and a set of them displayed tissue-specific expression. Notably, 11 CsWRKY genes exhibited significant expression changes in seedlings under cold, salt, and drought stresses, showing a preferentially inducible expression pattern in response to the stress. CONCLUSIONS: The present article describes a detailed analysis of the CsWRKY gene family and its expression profiles in 12 tissues and under several stress conditions. Segmental duplication is the major force underlying the broad expansion of this gene family, and a strong purifying pressure occurred for CsWRKY proteins during their evolution. CsWRKY proteins play important roles in plant development, with differential functions in different tissues. Exceptionally, eleven CsWRKYs, particularly five alternative spliced isoforms, were found to be the possible key players in mediating plant responses to various stresses. Overall, our results provide a foundation for understanding the roles of CsWRKYs and the precise mechanism through which CsWRKYs regulate high stress resistance as well as the development of stress tolerance cultivars among Cruciferae crops.


Assuntos
Genoma de Planta , Proteínas de Plantas , Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética
10.
Plant Physiol Biochem ; 156: 323-332, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32998099

RESUMO

Purple-fleshed sweetpotato (PFSP) accumulates high amounts of anthocyanins that are beneficial to human health. Although biosynthesis of such secondary metabolites has been well studied in aboveground organs of many plants, the mechanisms underlying anthocyanin accumulation in underground tuberous roots of sweetpotato are less understood. To identify genes and metabolites involved in anthocyanin accumulation in sweetpotato, we performed comparative transcriptomic and metabolomic analysis of (PFSP) and white-fleshed sweetpotato (WFSP). Anthocyanin-targeted metabolome analysis revealed that delphinidin, petunidin, and rosinidin were the key metabolites conferring purple pigmentation in PFSP as they were highly enriched in PFSP but absent in WFSP. Transcriptomic analysis identified 358 genes that were potentially implicated in multiple pathways for the biosynthesis of anthocyanins. Although most of the genes were previously known for their roles in anthocyanin biosynthesis, we identified 26 differentially expressed genes that are involved in Aux/IAA-ARF signaling. Gene-metabolite correlation analysis also revealed novel genes that are potentially involved in the anthocyanin accumulation in sweetpotato. Taken together, this study provides insights into the genes and metabolites underlying anthocyanin enrichment in underground tuberous roots of sweetpotato.


Assuntos
Antocianinas/biossíntese , Ipomoea batatas , Metaboloma , Raízes de Plantas/metabolismo , Transcriptoma , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Pigmentação
11.
Comput Intell Neurosci ; 2020: 1242781, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32831817

RESUMO

Ultrasonography is widely used in the clinical diagnosis of thyroid nodules. Ultrasound images of thyroid nodules have different appearances, interior features, and blurred borders that are difficult for a physician to diagnose into malignant or benign types merely through visual recognition. The development of artificial intelligence, especially deep learning, has led to great advances in the field of medical image diagnosis. However, there are some challenges to achieve precision and efficiency in the recognition of thyroid nodules. In this work, we propose a deep learning architecture, you only look once v3 dense multireceptive fields convolutional neural network (YOLOv3-DMRF), based on YOLOv3. It comprises a DMRF-CNN and multiscale detection layers. In DMRF-CNN, we integrate dilated convolution with different dilation rates to continue passing the edge and the texture features to deeper layers. Two different scale detection layers are deployed to recognize the different sizes of the thyroid nodules. We used two datasets to train and evaluate the YOLOv3-DMRF during the experiments. One dataset includes 699 original ultrasound images of thyroid nodules collected from a local health physical center. We obtained 10,485 images after data augmentation. Another dataset is an open-access dataset that includes ultrasound images of 111 malignant and 41 benign thyroid nodules. Average precision (AP) and mean average precision (mAP) are used as the metrics for quantitative and qualitative evaluations. We compared the proposed YOLOv3-DMRF with some state-of-the-art deep learning networks. The experimental results show that YOLOv3-DMRF outperforms others on mAP and detection time on both the datasets. Specifically, the values of mAP and detection time were 90.05 and 95.23% and 3.7 and 2.2 s, respectively, on the two test datasets. Experimental results demonstrate that the proposed YOLOv3-DMRF is efficient for detection and recognition of thyroid nodules for ultrasound images.

12.
Sensors (Basel) ; 20(13)2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635280

RESUMO

With the increasing adoption of the Internet-of-Things (IoT), the wireless sensors network (WSN), as an underlying application of IoT, has attracted increasing attention. Topology, the working structure used to observe WSN, is the most instinctive form in troubleshooting and has great significance to WSN management and safety. To this end, it is imperative to recover WSN topology for the purpose of network management and non-cooperative network detection. Traditional network topology recovery mainly relies on the monitoring modules installed in nodes, or an extra network attached. However, these two approaches have several limitations, such as high energy consumption for monitoring nodes, time synchronization problems, reuse failure, limitation to specific targeted networks and high cost. In this paper, we present a new approach to recover the topology of WSN that adopts location-based routing protocols, based on movable platforms. Our observation is that the network topology is consistent with the node routing, as the nodes choose the next hop according to the geological position of neighbor nodes. Hence, we calculate the cost parameters of choosing routing nodes for the targeted network according to the partial connection of the nodes. Based on those cost parameters, we can determine the topology of the whole network. More specifically, by collecting the geological position and data packets of the nodes from movable platforms, we are able to infer the topology of the WSN according to the recovered partial connection of nodes. Our approach can be easily adopted to many scenarios, especially for non-cooperative large-scale networks. The evaluation of 30 simulations shows that the accuracy of recovery is above 90%.

13.
Plant Physiol Biochem ; 154: 379-386, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32623093

RESUMO

Sweetpotato (Ipomoea batatas. L) is an important food crop, harvested for its nutrient-rich tuberous roots. Drought and salt stresses are two major factors limiting the sweetpotato production. Since microRNAs (miRNAs) are well known to play crucial roles in regulation of plant stress responses, quantitative profiling of miRNA expression under stress conditions will facilitate identification and genetic manipulation of novel miRNAs to improve stress tolerance. Real-time quantitative reverse transcription PCR (qRT-PCR) is a commonly used tool for this purpose, but not without challenges. Although stem-loop and poly(A)-tail modified qRT-PCR methods were developed for characterizing miRNA expression, accurate profiling of miRNAs is still difficult in many plant species because of a lack of reliable reference genes for normalizing miRNA transcripts. To identify reference genes that are suitable for normalizing miRNA expression in sweetpotato, the expression stability of eight candidate miRNAs and two commonly used reference genes were tested in 96 samples involving four tissues and two cultivars under drought and salt stress treatments. Data analysis using the geNorm, NormFinder and Bestkeeper algorithms demonstrated that miRn60, miR482, and their combination were reliable references. We further validated the reference genes by expression analysis of the well-characterized miR319 and miR156 that regulate drought and salt stress responses, respectively. The reference genes identified in this study will facilitate future miRNA analysis under abiotic stress conditions in sweetpotato.


Assuntos
Regulação da Expressão Gênica de Plantas , Ipomoea batatas , MicroRNAs/genética , Estresse Fisiológico , Perfilação da Expressão Gênica , Ipomoea batatas/genética , RNA de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Padrões de Referência , Transcrição Reversa
14.
Ying Yong Sheng Tai Xue Bao ; 31(2): 625-633, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32476357

RESUMO

We isolated bacteria from the phycosphere of Scenedesmus obliques and sequenced 16S rDNAs to establish algae-bacterial co-culture systems. Further, we examined effects of the bacteria on algal growth, and parameters associated with physio-biochemical and oil-producing characteristics of S. obliquus. Seven bacterial strains were isolated, including Micrococcus (strains 1-1, 1-2 and 1-3), Pseudomonas sp. (strains 2-1 and 2-2), Exiguobacterium (strain-3) and Staphylococcus sp. (strain-4). Among them, two bacteria (strain 1-2 and strain 2-1) were characterized as the dominant growth-promoting bacterial strains, which significantly increased algal growth, pigment production, and oil enrichment. After eight days cultivation under microalgal-bacterial (strain 1-2) symbiotic systemat at an initial ratio of 1:10, biomass of S. obliquus was 4.27 g·L-1, about 46.0% higher than that of the control. The contents of chlorophyll a, chlorophyll b and carotenoids were increased by 12.1%, 16.7% and 25.0%, respectively. Oil content was increased by 14.0% and reached to 25.7%, and the oleic acid content was significantly higher than that of the control and up to 16.4%. When co-cultured with Pseudomonas sp. (strain 2-1) for eight days at an initial ratio of 1:5, algal biomass, chlorophyll a, chlorophyll b and carotenoids contents were higher than that of the control by 47.9%, 16.0%, 17.5% and 19.9%, respectively. The total oil (27.1%) and oleic acid (18.2%) contents were increased by 20.4% and 64.0%, respectively. We concluded that Micrococcus (strain 1-2) and Pseudomonas sp. (strain 2-1) could significantly promote algal growth and increase oil production by their beneficial interaction with S. obliques, which could be potentially used in commercial production of S. obliques.


Assuntos
Microalgas , Scenedesmus , Bactérias , Biomassa , Clorofila A
15.
BMC Plant Biol ; 20(1): 275, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539793

RESUMO

BACKGROUND: Human demand for wheat will continue to increase together with the continuous global population growth. Agronomic traits in wheat are susceptible to environmental conditions. Therefore, in breeding practice, priority is given to QTLs of agronomic traits that can be stably detected across multiple environments and over many years. RESULTS: In this study, QTL analysis was conducted for eight agronomic traits using an introgression line population across eight environments (drought stressed and well-watered) for 5 years. In total, 44 additive QTLs for the above agronomic traits were detected on 15 chromosomes. Among these, qPH-6A, qHD-1A, qSL-2A, qHD-2D and qSL-6A were detected across seven, six, five, five and four environments, respectively. The means in the phenotypic variation explained by these five QTLs were 12.26, 9.51, 7.77, 7.23, and 8.49%, respectively. CONCLUSIONS: We identified five stable QTLs, which includes qPH-6A, qHD-1A, qSL-2A, qHD-2D and qSL-6A. They play a critical role in wheat agronomic traits. One of the dwarf genes Rht14, Rht16, Rht18 and Rht25 on chromosome 6A might be the candidate gene for qPH-6A. The qHD-1A and qHD-2D were novel stable QTLs for heading date and they differed from known vernalization genes, photoperiod genes and earliness per se genes.


Assuntos
Introgressão Genética , Traços de História de Vida , Fenótipo , Melhoramento Vegetal , Locos de Características Quantitativas , Triticum/genética , Meio Ambiente , Triticum/metabolismo
16.
Food Funct ; 11(5): 4659-4671, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32405635

RESUMO

The aim of this study is to probe a new function of astaxanthin (AST) from Haematococcus pluvialis on chemotherapeutic drug induced liver injury in mice. Doxorubicin-induced liver injury was treated with different doses of AST, and the body weight, food intake, urinalysis, liver function, and oxidative stress indexes were examined. The hepatocyte apoptosis level, pathological sections of liver tissue and the expression of antioxidant related genes were also determined. This study found that DOX could induce serious liver injury through cytotoxicity. AST treatment could decrease the level of liver function indexes (ALT, GOT, ALP and TBil), reduce the concentration of MDA and ROS, and increase the activities of SOD, CAT and GPX in the liver. AST could also repair the damaged hepatocyte in mice with liver injury and reduce the degree of the cellular apoptosis. In addition, AST could interfere with the expression of some related genes in the Keap1/Nrf2 signaling pathway by downregulating the expression of Keap1 and activating the transcription factor Nrf2 via enhancing the level of ERK, which upregulates downstream peroxiredoxins. The present research found and illustrated a new food function of AST, indicating that AST could be used in the therapy of chemotherapy induced side effects.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Clorófitas , Cirrose Hepática/prevenção & controle , Substâncias Protetoras/uso terapêutico , Animais , Antineoplásicos/efeitos adversos , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Doxorrubicina/efeitos adversos , Hepatócitos/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fator 2 Relacionado a NF-E2/metabolismo , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/farmacologia , Xantofilas/administração & dosagem , Xantofilas/farmacologia , Xantofilas/uso terapêutico
17.
Mol Aspects Med ; 76: 100859, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32386845

RESUMO

NOD-like receptor family pyrin domain containing 6 (NLRP6) is a novel NLR family member, that shows high expression in the intestine and liver (in contrast to NLRP3 in myeloid cells), to regulate inflammation and host defense against microbes. NLRP6 is reported to involved in inflammasome activation, regulation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling, antiviral interferon (IFN) signaling, mucus secretion, and antimicrobial peptide (AMP) production. Here, we discuss the recent findings as well as debates regarding: how NLRP6 is induced ("signal I″) and activated ("signal II"); its roles in intestinal cells and immune cells; how NLRP6 and NLRP9 coordinate to regulate the anti-viral immune response in the intestine; potential targeting of NLRP6 in human diseases.

18.
Protein Expr Purif ; 172: 105633, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32259580

RESUMO

A full-length cDNA sequence of plant type CRY (designated Hae-P-CRY) was cloned from the green alga Haematococcus pluvialis. The cDNA sequence was 3608 base pairs (bp) in length, which contained a 2988-bp open reading frame encoding 995 amino acids with molecular mass of 107.7 kDa and isoelectric point of 6.19. Multiple alignment analysis revealed that the deduced amino acid sequence of Hae-P-CRY shared high identity of 47-66% with corresponding plant type CRYs from other eukaryotes. The catalytic motifs of plant type CRYs were detected in the amino acid sequence of Hae-P-CRY including the typical PHR and CTE domains. Phylogenetic analysis showed that the Hae-P-CRY was grouped together with other plant type CRYs from green algae and higher plants, which distinguished from other distinct groups. The transcriptional level of Hae-P-CRY was strongly decreased after 0-4 h under HL stress. In addition, the Hae-P-CRY gene was heterologously expressed in Escherichia coli BL21 (DE3) and successfully purified. The typical spectroscopic characteristics of plant type CRYs were present in Hae-P-CRY indicated that it may be an active enzyme, which provided valuable clue for further functional investigation in the green alga H. pluvialis. These results lay the foundation for further function and interaction protein identification involved in CRYs mediated signal pathway under HL stress in H. pluvialis.


Assuntos
Clorófitas/genética , Clonagem Molecular , Criptocromos , Expressão Gênica , Criptocromos/biossíntese , Criptocromos/química , Criptocromos/genética , Criptocromos/isolamento & purificação , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
19.
Sheng Wu Gong Cheng Xue Bao ; 36(4): 716-731, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32347066

RESUMO

Stearoyl-ACP Δ9 desaturase (SAD) catalyzes the synthesis of monounsaturated oleic acid or palmitoleic acid in plastids. SAD is the key enzyme to control the ratio of saturated fatty acids to unsaturated fatty acids in plant cells. In order to analyze the regulation mechanism of soybean oleic acid synthesis, soybean (Glycine max) GmSAD family members were genome-wide identified, and their conserved functional domains and physicochemical properties were also analyzed by bioinformatics tools. The spatiotemporal expression profile of each member of GmSADs was detected by qRT-PCR. The expression vectors of GmSAD5 were constructed. The enzyme activity and biological function of GmSAD5 were examined by Agrobacterium-mediated transient expression in Nicotiana tabacum leaves and genetic transformation of oleic acid-deficient yeast (Saccharomyces cerevisiae) mutant BY4389. Results show that the soybean genome contains five GmSAD family members, all encoding an enzyme protein with diiron center and two conservative histidine enrichment motifs (EENRHG and DEKRHE) specific to SAD enzymes. The active enzyme protein was predicted as a homodimer. Phylogenetic analysis indicated that five GmSADs were divided into two subgroups, which were closely related to AtSSI2 and AtSAD6, respectively. The expression profiles of GmSAD members were significantly different in soybean roots, stems, leaves, flowers, and seeds at different developmental stages. Among them, GmSAD5 expressed highly in the middle and late stages of developmental seeds, which coincided with the oil accumulation period. Transient expression of GmSAD5 in tobacco leaves increased the oleic acid and total oil content in leaf tissue by 5.56% and 2.73%, respectively, while stearic acid content was reduced by 2.46%. Functional complementation assay in defective yeast strain BY4389 demonstrated that overexpression of GmSAD5 was able to restore the synthesis of monounsaturated oleic acid, resulting in high oil accumulation. Taken together, soybean GmSAD5 has strong selectivity to stearic acid substrates and can efficiently catalyze the biosynthesis of monounsaturated oleic acid. It lays the foundation for the study of soybean seed oleic acid and total oil accumulation mechanism, providing an excellent target for genetic improvement of oil quality in soybean.


Assuntos
Ácidos Graxos Dessaturases , Proteínas de Plantas , Soja , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Perfilação da Expressão Gênica , Ácido Oleico/biossíntese , Filogenia , Proteínas de Plantas/genética , Sementes/química , Soja/classificação , Soja/enzimologia , Soja/genética
20.
Front Plant Sci ; 11: 11, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117362

RESUMO

Camelina sativa (L.) Crantz is an important Brassicaceae oil crop with a number of excellent agronomic traits including low water and fertilizer input, strong adaptation and resistance. Furthermore, its short life cycle and easy genetic transformation, combined with available data of genome and other "-omics" have enabled camelina as a model oil plant to study lipid metabolism regulation and genetic improvement. Particularly, camelina is capable of rapid metabolic engineering to synthesize and accumulate high levels of unusual fatty acids and modified oils in seeds, which are more stable and environmentally friendly. Such engineered camelina oils have been increasingly used as the super resource for edible oil, health-promoting food and medicine, biofuel oil and high-valued chemical production. In this review, we mainly highlight the latest advance in metabolic engineering towards the predictive manipulation of metabolism for commercial production of desirable bio-based products using camelina as an ideal platform. Moreover, we deeply analysis camelina seed metabolic engineering strategy and its promising achievements by describing the metabolic assembly of biosynthesis pathways for acetyl glycerides, hydroxylated fatty acids, medium-chain fatty acids, ω-3 long-chain polyunsaturated fatty acids, palmitoleic acid (ω-7) and other high-value oils. Future prospects are discussed, with a focus on the cutting-edge techniques in camelina such as genome editing application, fine directed manipulation of metabolism and future outlook for camelina industry development.

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