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911.
Laleh Shariati Mehran Modaress Hossein Khanahmad Zahra Hejazi Mohammad Amin Tabatabaiefar Mansoor Salehi Mohammad Hossein Modarressi 《Biotechnology letters》2016,38(8):1243-1250
Objective
To compare methods for erythroid differentiation of K562 cells that will be promising in the treatment of beta-thalassemia by inducing γ-globin synthesis.Results
Cells were treated separately with: RPMI 1640 medium without glutamine, RPMI 1640 medium without glutamine supplemented with 1 mM sodium butyrate, RPMI 1640 medium supplemented with 1 mM sodium butyrate, 25 µg cisplatin/ml, 0.1 µg cytosine arabinoside/ml. The highest differentiation (84 %) with minimum toxicity was obtained with cisplatin at 15 µg /ml. Real-time RT-PCR showed that expression of the γ-globin gene was significantly higher in the cells differentiated with cisplatin compared to undifferentiated cells (P < 0.001).Conclusions
Cisplatin is useful in the experimental therapy of ß-globin gene defects and can be considered for examining the basic mechanism of γ-reactivation.912.
Diego Lucero Ozan Dikilitas Michael M. Mendelson Zahra Aligabi Promotto Islam Edward B. Neufeld Aruna T. Bansal Lita A. Freeman Boris Vaisman Jingrong Tang Christian A. Combs Yuesheng Li Szilard Voros Iftikhar J. Kullo Alan T. Remaley 《Journal of lipid research》2022,63(1):100160
A significant proportion of patients with elevated LDL and a clinical presentation of familial hypercholesterolemia do not carry known genetic mutations associated with hypercholesterolemia, such as defects in the LDL receptor. To identify new genes involved in the cellular uptake of LDL, we developed a novel whole-genome clustered regularly interspaced short palindromic repeat-Cas9 KO screen in HepG2 cells. We identified transgelin (TAGLN), an actin-binding protein, as a potentially new gene involved in LDL endocytosis. In silico validation demonstrated that genetically predicted differences in expression of TAGLN in human populations were significantly associated with elevated plasma lipids (triglycerides, total cholesterol, and LDL-C) in the Global Lipids Genetics Consortium and lipid-related phenotypes in the UK Biobank. In biochemical studies, TAGLN-KO HepG2 cells showed a reduction in cellular LDL uptake, as measured by flow cytometry. In confocal microscopy imaging, TAGLN-KO cells had disrupted actin filaments as well as an accumulation of LDL receptor on their surface because of decreased receptor internalization. Furthermore, TAGLN-KO cells exhibited a reduction in total and free cholesterol content, activation of SREBP2, and a compensatory increase in cholesterol biosynthesis. TAGLN deficiency also disrupted the uptake of VLDL and transferrin, other known cargoes for receptors that depend upon clathrin-mediated endocytosis. Our data suggest that TAGLN is a novel factor involved in the actin-dependent phase of clathrin-mediated endocytosis of LDL. The identification of novel genes involved in the endocytic uptake of LDL may improve the diagnosis of hypercholesterolemia and provide future therapeutic targets for the prevention of cardiovascular disease. 相似文献
913.
Sepideh Khazeni Fatemeh Yazdian Zahra Beagom Mokhtari-Hosseini Bahman Ebrahimi-Hosseinzadeh Behnam Noorani 《Preparative biochemistry & biotechnology》2017,47(4):371-378
Bacterial cellulose (BC) is a very fascinating microbial biopolymer which is mainly produced by Gluconacetobacter xylinum. Optimization of BC production by G. xylinum was performed based on scale-down studies in miniature-bioreactor and response surface methodology in which the optimum pH value (6.5) and shaking rate (50?rpm) were obtained. The static culture condition for BC production has newly been defined. Nanostructure of BC includes nanofibers up to (60?nm) and nanoporosity up to (265?nm) was observed by scanning electron microscopy. By Fourier transform infrared spectroscopy study, the most expected BC interaction is nucleophilic interaction. MTT assay showed high biocompatibility. Appropriate mechanical strength (0.37?MPa) and Young’s modulus (3.36?MPa) evinced BC scaffold utilization for skin tissue. The results indicate that BC sheets can be utilized in biomedical application and nanotechnology approaches. 相似文献
914.
The vernalization gene 2 (VRN2), is a major flowering repressor in temperate cereals that is regulated by low temperature and photoperiod. Here we show that the gene from Triticum aestivum (TaVRN2) is also regulated by salt, heat shock, dehydration, wounding and abscissic acid. Promoter analysis indicates that TaVRN2 regulatory region possesses all the specific responsive elements to these stresses. This suggests pleiotropic effects of TaVRN2 in wheat development and adaptability to the environment. To test if TaVRN2 can act as a flowering repressor in species different from the temperate cereals, the gene was ectopically expressed in the model plant Arabidopsis. Transgenic plants showed no alteration in morphology, but their flowering time was significantly delayed compared to controls plants, indicating that TaVRN2, although having no ortholog in Brassicaceae, can act as a flowering repressor in these species. To identify the possible mechanism by which TaVRN2 gene delays flowering in Arabidopsis, the expression level of several genes involved in flowering time regulation was determined. The analysis indicates that the late flowering of the 35S::TaVRN2 plants was associated with a complex pattern of expression of the major flowering control genes, FCA, FLC, FT, FVE and SOC1. This suggests that heterologous expression of TaVRN2 in Arabidopsis can delay flowering by modulating several floral inductive pathways. Furthermore, transgenic plants showed higher freezing tolerance, likely due to the accumulation of CBF2, CBF3 and the COR genes. Overall, our data suggests that TaVRN2 gene could modulate a common regulator of the two interacting pathways that regulate flowering time and the induction of cold tolerance. The results also demonstrate that TaVRN2 could be used to manipulate flowering time and improve cold tolerance in other species. 相似文献
915.
Omid Panahi Shadi Delkhoon Zahra Lak 《Archives Of Phytopathology And Plant Protection》2013,46(17):2009-2013
Lecanicillium longisporum is one of the facultative insect pathogens with significant host range and host specificity. The conidia survival may be affected by environmental factors or by bio-pesticides and chemical products used to protect crop plants. In this research, the compatibility of the mentioned fungi with acetamipride and imidaclopride and the effect of these insecticides on conidial germination and vegetative growth were studied. The formulations of insecticides were tested in three concentrations (mean concentration (MC), half MC and twice the MC). The study was conducted in completely randomised design (CRD) with four replications. The results indicated that acetamipride and imidaclopride in half MC were compatible with L. longisporum (isolate LRC195). However, based on the results, imidacloprid compared to acetamipride is adaptable with L. longisporum. These insecticides could be used simultaneously in low concentration with this entomopathogenic fungus in integrated pest management. 相似文献
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920.
Greice Krautz-Peterson Mariana Simoes Zahra Faghiri David Ndegwa Guilherme Oliveira Charles B. Shoemaker Patrick J. Skelly 《PLoS pathogens》2010,6(6)
Adult schistosomes live in the host''s bloodstream where they import nutrients such as glucose across their body surface (the tegument). The parasite tegument is an unusual structure since it is enclosed not by the typical one but by two closely apposed lipid bilayers. Within the tegument two glucose importing proteins have been identified; these are schistosome glucose transporter (SGTP) 1 and 4. SGTP4 is present in the host interactive, apical tegumental membranes, while SGTP1 is found in the tegumental basal membrane (as well as in internal tissues). The SGTPs act by facilitated diffusion. To examine the importance of these proteins for the parasites, RNAi was employed to knock down expression of both SGTP genes in the schistosomula and adult worm life stages. Both qRT-PCR and western blotting analysis confirmed successful gene suppression. It was found that SGTP1 or SGTP4-suppressed parasites exhibit an impaired ability to import glucose compared to control worms. In addition, parasites with both SGTP1 and SGTP4 simultaneously suppressed showed a further reduction in capacity to import glucose compared to parasites with a single suppressed SGTP gene. Despite this debility, all suppressed parasites exhibited no phenotypic distinction compared to controls when cultured in rich medium. Following prolonged incubation in glucose-depleted medium however, significantly fewer SGTP-suppressed parasites survived. Finally, SGTP-suppressed parasites showed decreased viability in vivo following infection of experimental animals. These findings provide direct evidence for the importance of SGTP1 and SGTP4 for schistosomes in importing exogenous glucose and show that these proteins are important for normal parasite development in the mammalian host. 相似文献