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We previously found by using yeast, Candida maltosa, that cycloheximide (CYH) sensitivity of ribosomes is dependent on the 56th amino acid residues of a ribosomal protein, L413 (proline in sensitive and glutamine in resistant ribosomes). We also revealed that in this yeast, which has both L41-P type and L41-Q type genes, the expression of the latter type genes is induced by the addition of CYH in the medium to make the cells inducibly resistant to CYH. In this paper, we analyzed the promoter region of L41-Q2a, one of the CYH-inducible L41-Q type genes and found two elements required for the induction of expression: one was a GCRE (Gcn4p-responsive element of Saccharomyces cerevisiae)-like element and the other was a GT-rich element. This promoter region was also required for its expression under some other growth inhibitory conditions. Furthermore, it was suggested that Q-type ribosomes synthesized under these conditions are more resistant to these inhibitory conditions.  相似文献   

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Aims: To degrade ether‐type polyurethane (ether‐PUR), ether‐PUR–degrading micro‐organism was isolated. Moreover, ether‐PUR–degrading mechanisms were analysed using model compounds of ether‐PUR. Methods and Results: A fungus designated as strain PURDK2, capable of changing the configuration of ether‐PUR, has been isolated. This isolated fungus was identified as Alternaria sp. Using a scanning electron microscope, the grid structure of ether‐PUR was shown to be melted and disrupted by the fungus. The degradation of ether‐PUR by the fungus was analysed, and the ether‐PUR was degraded by the fungus by about 27·5%. To analyse the urethane‐bond degradation by the fungus, a degraded product of ethylphenylcarbamate was analysed using GC/MS. Aniline and ethanol were detected by degradation with the supernatant, indicating that the fungus secreted urethane‐bond–degrading enzyme(s). PURDK2 also degraded urea bonds when diphenylmethane‐4,4′‐dibutylurea was used as a substrate. Conclusions: The enzyme(s) from PURDK2 degraded urethane and urea bonds to convert the high molecular weight structure of ether‐PUR to small molecules; and then the fungus seems to use the small molecules as an energy source. Significance and Impact of the Study: Ether‐PUR–degrading fungus, strain PURDK2, was isolated, and the urethane‐ and urea‐bonds–degrading enzymes from strain PURDK2 could contribute to the material recycling of ether‐PUR.  相似文献   

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This study aims to explore the predictive noninvasive biomarker for obstructive coronary artery disease (CAD). By using the data set GSE90074, weighted gene co-expression network analysis (WGCNA), and protein–protein interactive network, construction of differentially expressed genes in peripheral blood mononuclear cells was conducted to identify the most significant gene clusters associated with obstructive CAD. Univariate and multivariate stepwise logistic regression analyses and receiver operating characteristic analysis were used to predicate the diagnostic accuracy of biomarker candidates in the detection of obstructive CAD. Furthermore, functional prediction of candidate gene biomarkers was further confirmed in ST-segment elevation myocardial infarction (STEMI) patients or stable CAD patients by using the datasets of GSE62646 and GSE59867. We found that the blue module discriminated by WGCNA contained 13 hub-genes that could be independent risk factors for obstructive CAD (P < .05). Among these 13 hub-genes, a four-gene signature including neutrophil cytosol factor 2 (NCF2, P = .025), myosin-If (MYO1F, P = .001), sphingosine-1-phosphate receptor 4 (S1PR4, P = .015), and ficolin-1 (FCN1, P = .012) alone or combined with two risk factors (male sex and hyperlipidemia) may represent potential diagnostic biomarkers in obstructive CAD. Furthermore, the messenger RNA levels of NCF2, MYO1F, S1PR4, and FCN1 were higher in STEMI patients than that in stable CAD patients, although S1PR4 showed no statistical difference (P > .05). This four-gene signature could also act as a prognostic biomarker to discriminate STEMI patients from stable CAD patients. These findings suggest a four-gene signature (NCF2, MYO1F, S1PR4, and FCN1) alone or combined with two risk factors (male sex and hyperlipidemia) as a promising prognostic biomarker in the diagnosis of STEMI. Well-designed cohort studies should be implemented to warrant the diagnostic value of these genes in clinical purpose.  相似文献   

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The NeIF-4A10 gene belongs to a family of at least ten genes, all of which encode closely related isoforms of translation initiation factor 4A. The promoter region of NeIF-4A10 was sequenced, and four mRNA 5 ends were determined. Deletions containing 2750, 689 and 188 bp of untranscribed upstream DNA were fused to the GUS reporter gene and introduced into transgenic tobacco. The three constructs mediated GUS expression in all cells of the leaf, stem and shoot apical meristem. Control experiments using in situ hybridization and tissue printing indicated that the observed GUS expression matches the expression patterns of NeIF-4A mRNA and protein. This detailed analysis at the level of mRNA, protein and reporter gene expression shows that NeIF-4A10 is an ideal constitutively expressed control gene. We argue that inclusion of such a control gene in experiments dealing with specifically expressed genes is in many cases essential for the correct interpretation of observed expression patterns.  相似文献   

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Extracellular vesicles (EVs) have potential as minimally invasive biomarkers. However, the methods most commonly used for EV retrieval rely on ultracentrifugation, are time-consuming, and unrealistic to translate to standard-of-care. We sought a method suitable for EV separation from blood that could be used in patient care. Sera from breast cancer patients and age-matched controls (n = 27 patients; n = 36 controls) were analysed to compare 6 proposed EV separation methods. The EVs were then characterised on 8 parameters. The selected method was subsequently applied to independent cohorts of sera (n = 20 patients; n = 20 controls), as proof-of-principle, investigating EVs’ gremlin-1 cargo. Three independent runs with each method were very reproducible, within each given method. All isolates contained EVs, although they varied in quantity and purity. Methods that require ultracentrifugation were not superior for low volumes of sera typically available in routine standard-of-care. A CD63/CD81/CD9-coated immunobead-based method was most suitable based on EV markers'' detection and minimal albumin and lipoprotein contamination. Applying this method to independent sera cohorts, EVs and their gremlin-1 cargo were at significantly higher amounts for breast cancer patients compared to controls. In conclusion, CD63/CD81/CD9-coated immunobeads may enable clinical utility of blood-based EVs as biomarkers.  相似文献   

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Abstract

The Agrobacterium-mediated ability to transfer genes into organisms without sexual crossing provides breeders with new opportunities to improve the efficiency of plant production. Gene transfer offers advantages over classical genetic manipulation since plants are improved without disruption of the integrity of their genomes. Several useful genes isolated from microrganisms and affecting pest resistance, rooting ability, hormonal metabolism etc., are now available. These genes can be easily cloned into suitable Ti and Ri derived plasmid vectors and transferred into woody species. The scarce ability of most fruit trees to regenerate the whole plant from in vitro-cultured cells remains the main obstacle to a wider use of gene transfer technology.  相似文献   

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Potato tuber moth (PTM), Phthorimaea operculella, is a serious pest of stored potato in most countries where potatoes are grown. Entomopathogens offer promise as alternatives to broad spectrum insecticides for management of this pest. The fungus Muscodor albus, which produces a mixture of antimicrobial volatile organic chemicals, was tested for its insecticidal activity against PTM. Adults and neonate larvae were exposed to volatiles generated by 15 or 30 g of M. albus rye grain culture plus water for 72 h in hermetically sealed 28.3 L chambers at 24 degrees C. Mean percent mortalities in adult moths exposed to 0, 15, and 30 g of fungal formulation were 0.9, 84.6, and 90.6%, respectively. Development to the pupal stage of PTM that were exposed as neonate larvae to 15 or 30 of M. albus culture was reduced by 61.8 and 72.8%, respectively, relative to controls.  相似文献   

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The effect of nutritional conditions on spore qualities was investigated in order to select which propagules, conidia or chlamydospores, would be most suitable for mycoherbicide development. Plectosporium alismatis was grown in a liquid basal medium supplemented with glucose and a mineral nitrogen source (sodium nitrate) or an organic nitrogen source (casamino acids). Conidial and chlamydospore yields, germination rate and shelf-life were compared. Two growth models were developed: on one hand, sodium nitrate added as the sole nitrogen source was partially utilised (8%), resulting in poor growth (1.77±0.02 mg mL?1; 6±1.7×105 conidia mL?1). Under these conditions, P. alismatis produced dense, melanised-like aggregates that contained chlamydospores (12.4±0.7×104 chlamydospores mL?1). Germination rates of chlamydospores and conidia produced under these conditions was high (80%). Twenty percent of chlamydospores were able to germinate after 4 months storage at 25°C, while survival of conidia declined rapidly (<2%). When casamino acids were added to the liquid medium as the sole nitrogen source, P. alismatis produced sparser pellets resulting in high dry weights (5.37±0.09 mg mL?1 and high conidia numbers (9.6±1.5×106 conidia mL?1), while no chlamydospore were observed. The germination rate of conidia produced in casamino acids was low (33±13%) after 8 h incubation and microcycle conidiation occurred. Five percent of these conidia germinated after 4 months storage. These data indicate that chlamydospores may be suitable for mycoherbicide development, provided further optimisation of yields is achieved.  相似文献   

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H1-antihistamine has been shown to be effective in treating patients with allergic rhinitis (AR), but its mechanism is still uncertain. We investigated effects of histamine H1 receptor (HRH1) gene polymorphisms on the efficacy of oral H1-antihistamine in perennial patients with AR caused by mites in the Chinese Han population for the first time. A total of 224 Han Chinese patients with AR and 165 Han Chinese healthy volunteers were selected. Genotype and allele frequency distribution of −17C/T in HRH1 gene in patients with AR, serum levels of eosinophil cationic protein (ECP), total immunoglobulin E (IgE), and specific IgE were detected. The clinical symptoms of patients with AR were evaluated with visual analogue scale (VAS). Direct counting method was applied to calculate genotype and allele frequencies. Higher levels of serum ECP and total IgE were shown in the AR group. Moreover, patients with CT, TT, or CT+TT genotype increased the risk of AR incidence in the in the −17C/T site of HRH1, and CC genotype and CT+TT genotype were associated with gender, asthma, VAS score, total IgE level, and specific IgE level in patients with AR. In addition, oral administration of H1-antihistamines improves clinical symptoms of patients with AR. At last, patients with the CC genotype showed the increased efficacy of H1-antihistamines in patients with AR. Our study provides evidence that HRH1 gene polymorphisms may correlate with oral H1-antihistamine efficacy for the treatment of patients with AR, which can be used as a biological indicator of the prediction of therapeutic efficacy of patients with AR.  相似文献   

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 Seedlings of papaya (Carica papaya L. var. Solo) were transplanted to pots with or without an arbuscular mycorrhizal (AM) fungus (Gigaspora margarita Becker and Hall). After 3 months, half the plants were subjected to water stress by withdrawing irrigation. The leaf water potential (LWP) was measured during 20 days of water-stress treatment and then the plants were harvested. Root ethylene and 1-aminocyclopropane-1-carboxylic acid (ACC) concentrations were measured and plant fresh weight determined. The LWP decreased during the water-stress treatment and this decrease was more severe in the non-AM plants. Plant fresh weight was higher for AM than non-AM plants under both conditions. Under well-irrigated conditions, the ethylene concentration in the roots was increased by the presence of AM, although there was no significant difference between AM and non-AM roots in ACC levels. ACC increased in both AM and non-AM roots under water-stress conditions. The water-stress treatment resulted in a marked increase in ethylene concentration in non-AM roots but the concentration in AM roots was slightly lower than under normal conditions. Accepted: 7 July 2000  相似文献   

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