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111.
An autophagy-related gene Atg8 was cloned for the first time from wild emmer wheat, named as TdAtg8, and its role on autophagy under abiotic stress conditions was investigated. Examination of TdAtg8 expression patterns indicated that Atg8 expression was strongly upregulated under drought stress, especially in the roots when compared to leaves. LysoTracker(?) red marker, utilized to observe autophagosomes, revealed that autophagy is constitutively active in Triticum dicoccoides. Moreover, autophagy was determined to be induced in plants exposed to osmotic stress when compared to plants grown under normal conditions. Functional studies were executed in yeast to confirm that the TdATG8 protein is functional, and showed that the TdAtg8 gene complements the atg8?::kan MX yeast mutant strain grown under nitrogen deficiency. For further functional analysis, TdATG8 protein was expressed in yeast and analyzed using Western immunoblotting. Atg8-silenced plants were exposed to drought stress and chlorophyll and malondialdehyde (MDA) content measurements demonstrated that Atg8 plays a key role on drought stress tolerance. In addition, Atg8-silenced plants exposed to osmotic stress were found to have decreased Atg8 expression level in comparison to controls. Hence, Atg8 is a positive regulator in osmotic and drought stress response.  相似文献   
112.
Duabanga grandiflora (DC.) Walp. is an ethnomedicinally significant plant used to treat various illnesses, but there is little scientific evidence to support its use. This study explored the pharmacological activities of methanol extract of D. grandiflora stem barks (MEDG) through in vivo approaches in Swiss albino mice and a computer-aided molecular approach. The forced swimming test (FST), tail suspension test (TST), elevated plus maze (EPM), and hole board test (HBT) were used to determine anti-depressant and anxiolytic activity in experimental mice. In addition, anti-diarrheal studies were performed using castor oil-induced diarrhea, castor oil-induced enter pooling, and the charcoal-induced gastrointestinal motility test. MEDG showed substantial depletions in the immobility times in both FST and TST after treatment with the MEDG extract, whereas moderate anxiolytic activity was manifested at a higher dose (400 mg/kg) compared with the control. Correspondingly, MEDG extract revealed a significant reduction in wet feces and decreased the small intestinal transit of charcoal meal in castor oil-induced diarrhea and charcoal-induced gastrointestinal motility test. In the computer-aided molecular approaches, vanillin displayed a promising binding score for both anxiolytic and anti-diarrheal activities, while duabanganal C showed a promising score for the anti-depressant activity. The present experimental findings along with a computer-aided model conclude that MEDG could be a possible Phyto therapeutic agent with potential anti-depressant, anxiolytic and anti-diarrheal activity.  相似文献   
113.
Genome‐scale metabolic models are valuable tools for the design of novel strains of industrial microorganisms, such as Komagataella phaffii (syn. Pichia pastoris). However, as is the case for many industrial microbes, there is no executable metabolic model for K. phaffiii that confirms to current standards by providing the metabolite and reactions IDs, to facilitate model extension and reuse, and gene‐reaction associations to enable identification of targets for genetic manipulation. In order to remedy this deficiency, we decided to reconstruct the genome‐scale metabolic model of K. phaffii by reconciling the extant models and performing extensive manual curation in order to construct an executable model (Kp.1.0) that conforms to current standards. We then used this model to study the effect of biomass composition on the predictive success of the model. Twelve different biomass compositions obtained from published empirical data obtained under a range of growth conditions were employed in this investigation. We found that the success of Kp1.0 in predicting both gene essentiality and growth characteristics was relatively unaffected by biomass composition. However, we found that biomass composition had a profound effect on the distribution of the fluxes involved in lipid, DNA, and steroid biosynthetic processes, cellular alcohol metabolic process, and oxidation‐reduction process. Furthermore, we investigated the effect of biomass composition on the identification of suitable target genes for strain development. The analyses revealed that around 40% of the predictions of the effect of gene overexpression or deletion changed depending on the representation of biomass composition in the model. Considering the robustness of the in silico flux distributions to the changing biomass representations enables better interpretation of experimental results, reduces the risk of wrong target identification, and so both speeds and improves the process of directed strain development.  相似文献   
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115.
A new chiral perylene monoanhydride monoimide (1) with a sterically hindered chiral amine was successfully synthesized for further selective functionalization at terminal positions. At the same time, the chiral perylene diimide (2) with the same amine has been synthesized. The synthesized products were characterized using the data from NMR, IR, MS, UV-vis, DSC, TGA, elemental analysis and cyclic and square wave voltammetry. Compound 2 shows an excellent solubility of 200 mg mL(-1) in chloroform. The band gap energy (Eg), LUMO and HOMO energy values were 2.28, -3.77 and -6.05 eV for 2, respectively in chloroform. In solid state, the band gap energy (Eg), LUMO and HOMO energy values were 1.96, -4.22 and -6.18 eV for 1 and 1.92, -4.13 and -6.05 eV for 2, respectively. Whereas 1 (solid state: -0.58 and -0.69 V vs. ferrocene/ferrocenium couple) and 2 (in chloroform: -1.03 and -1.22 V vs. ferrocene/ferrocenium couple) show two reversible reduction steps, 2 exhibits only one reversible wave (solid state: -0.67 V vs. ferrocene/ferrocenium couple). The diffusion coefficients were determined as 1.91 x 10(-7) and 8.47 x 10(-7) cm2 s(-1) for 1 and 2 in solid state, respectively, and 1.27 x 10(-5) cm2 s(-1) for 2 in solution. The solid state emission ability of the chiral products ( is much more emissive than ) remains a challenge for photonic, electronic and sensor applications. 1 and 2 showed high thermal stability. Efficient prevention of intermolecular pi-pi contacts of fluorophores results in an excellent fluorescence emission in solid state and solubility for 2.  相似文献   
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Lentil (Lens culinaris Medik.) is an excellent source of protein and carbohydrates and is also rich in essential trace elements for the human diet. Selenium (Se) is an essential micronutrient for human health and nutrition, providing protection against several diseases and regulating important biological systems. Dietary intake of 55 μg of Se per day is recommended for adults, with inadequate Se intake causing significant health problems. The objective of this study was to identify and map quantitative trait loci (QTL) of genes controlling Se accumulation in lentil seeds using a population of 96 recombinant inbred lines (RILs) developed from the cross “PI 320937” × “Eston” grown in three different environments for two years (2012 and 2013). Se concentration in seed varied between 119 and 883 μg/kg. A linkage map consisting of 1,784 markers (4 SSRs, and 1,780 SNPs) was developed. The map spanned a total length of 4,060.6 cM, consisting of 7 linkage groups (LGs) with an average distance of 2.3 cM between adjacent markers. Four QTL regions and 36 putative QTL markers, with LOD scores ranging from 3.00 to 4.97, distributed across two linkage groups (LG2 and LG5) were associated with seed Se concentration, explaining 6.3–16.9% of the phenotypic variation.  相似文献   
118.
AIM:To study the effect of both acute and chronic alcohol exposure on heme oxygenases(HOs) in the brain,liver and duodenum.METHODS:Wild-type C57BL/6 mice,heterozygous Sod2 knockout mice,which exhibit attenuated manganese superoxide dismutase activity,and liver-specific ARNT knockout mice were used to investigate the role of alcohol-induced oxidative stress and hypoxia.For acute alcohol exposure,ethanol was administered in the drinking water for 1 wk.Mice were pair-fed with regular or ethanol-containing Lieber De Carli liquid diets for 4 wk for chronic alcohol studies.HO expression was analyzed by real-time quantitative polymerase chain reaction and Western blotting.RESULTS:Chronic alcohol exposure downregulated HO-1 expression in the brain but upregulated it in the duodenum of wild-type mice.It did not alter liver HO-1 expression,nor HO-2 expression in the brain,liver or duodenum.In contrast,acute alcohol exposure decreased both liver HO-1 and HO-2 expression,and HO-2 expression in the duodenum of wild-type mice.The decrease in liver HO-1 expression was abolished in ARNT+/-mice.Sod2+/-mice with acute alcohol exposure did not exhibit any changes in liver HO-1 and HO-2 expression or in brain HO-2 expression.However,alcohol inhibited brain HO-1 and duodenal HO-2 but increased duodenal HO-1 expression in Sod2+/-mice.Collectively,these findings indicate that acute and chronic alcohol exposure regulates HO expression in a tissue-specific manner.Chronic alcohol exposure alters brain and duodenal,but not liver HO expression.However,acute alcohol exposure inhibits liver HO-1 and HO-2,and also duodenal HO-2 expression.CONCLUSION:The inhibition of liver HO expression by acute alcohol-induced hypoxia may play a role in the early phases of alcoholic liver disease progression.  相似文献   
119.
Regenerative ability varies tremendously across species. A common feature of regeneration of appendages such as limbs, fins, antlers, and tails is the formation of a blastema—a transient structure that houses a pool of progenitor cells that can regenerate the missing tissue. We have identified the expression of von Willebrand factor D and EGF domains (vwde) as a common feature of blastemas capable of regenerating limbs and fins in a variety of highly regenerative species, including axolotl (Ambystoma mexicanum), lungfish (Lepidosiren paradoxa), and Polpyterus (Polypterus senegalus). Further, vwde expression is tightly linked to the ability to regenerate appendages in Xenopus laevis. Functional experiments demonstrate a requirement for vwde in regeneration and indicate that Vwde is a potent growth factor in the blastema. These data identify a key role for vwde in regenerating blastemas and underscore the power of an evolutionarily informed approach for identifying conserved genetic components of regeneration.  相似文献   
120.
Radiotherapy (RT) has been used to control tumors by physically damaging DNA and inducing apoptosis; it also promotes antitumor immune responses via neoantigens release and augmenting immune-oncology agents to elicit systemic response. Tumor regression after RT can recruit inflammatory cells, such as tumor-associated macrophages and CD11b+ myeloid cell populations, a major subset of which may actually be immunosuppressive. However, these inflammatory cells also express Toll-like receptors (TLRs) that can be stimulated to reverse suppressive characteristics and promote systemic antitumor outcomes. Here, we investigated the effects of adding CMP-001, a CpG-A oligodeoxynucleotide TLR9 agonist delivered in a virus-like particle (VLP), to RT in two murine models (344SQ metastatic lung adenocarcinoma and CT26 colon carcinoma). High-dose RT (12Gy x 3 fractions) significantly increased the percentages of plasmacytoid dendritic cells within the tumor islets 3- and 5-days post-RT; adding CMP-001 after RT also enhanced adaptive immunity by increasing the proportion of CD4+ and CD8+ T cells. RT plus CMP-001-mediated activation of the immune system led to significant inhibition of tumor growth at both primary and abscopal tumor sites, thereby suggesting a new combinatorial treatment strategy for systemic disease.  相似文献   
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