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991.
Qingxia Fang Ting Liu Chenhuan Yu Xiuli Yang Yanfei Shao Jiana Shi Xiaolan Ye Xiaochun Zheng Jieping Yan Danfeng Xu Xiaozhou Zou 《Journal of cellular and molecular medicine》2020,24(6):3678-3691
The current study was designed to explore the role and underlying mechanism of lncRNA taurine up-regulated gene 1 (TUG1) in cardiac hypertrophy. Mice were treated by transverse aortic constriction (TAC) surgery to induce cardiac hypertrophy, and cardiomyocytes were treated by phenylephrine (PE) to induce hypertrophic phenotype. Haematoxylin-eosin (HE), wheat germ agglutinin (WGA) and immunofluorescence (IF) were used to examine morphological alterations. Real-time PCR, Western blots and IF staining were used to detect the expression of RNAs and proteins. Luciferase assay and RNA pull-down assay were used to verify the interaction. It is revealed that TUG1 was up-regulated in the hearts of mice treated by TAC surgery and in PE-induced cardiomyocytes. Functionally, overexpression of TUG1 alleviated cardiac hypertrophy both in vivo and in vitro. Mechanically, TUG1 sponged and sequestered miR-34a to increase the Dickkopf 1 (DKK1) level, which eventually inhibited the activation of Wnt/β-catenin signalling. In conclusion, the current study reported the protective role and regulatory mechanism of TUG1 in cardiac hypertrophy and suggested that TUG1 may serve as a novel molecular target for treating cardiac hypertrophy. 相似文献
992.
用于寡核苷酸芯片制备载体的醛基载玻片的制备方法优化及性质研究 总被引:11,自引:1,他引:11
优化了醛基载玻片的制备方法 ,探讨了醛基修饰载玻片固定寡核苷酸探针的性质。研究发现氨基硅烷试剂的浓度是影响载玻片荧光背景的主要因素 ;2 %氨基化试剂处理 16min、戊二醛处理 30min可以得到荧光背景较低、固定效果较好的醛基载玻片。寡核苷酸固定过程中 ,末端氨基修饰没有明显的特异性 ,但是可以提高被固定探针的杂交容量。在较低的浓度 (小于 10 μmol L)时 ,探针的浓度与杂交信号趋近线性关系 ,浓度为 2 0 μmol L时杂交信号达到饱和 相似文献
993.
Intersubgenomic heterosis in seed yield potential observed in a new type of Brassica napus introgressed with partial Brassica
rapa genome 总被引:2,自引:0,他引:2
Qian W Chen X Fu D Zou J Meng J 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,110(7):1187-1194
This paper reports the observation on the intersubgenomic heterosis for seed yield among hybrids between natural Brassica napus (AnAnCnCn) and a new type of B. napus with introgressions of genomic components of Brassica rapa (ArAr). This B. napus was selected from the progeny of B. napus × B. rapa and (B. napus × B. rapa) × B. rapa based on extensive phenotypic and cytological observation. Among the 129 studied partial intersubgenomic hybrids, which were obtained by randomly crossing 13 lines of the new type of B. napus in F3 or BC1F3 to 27 cultivars of B. napus from different regions as tester lines, about 90% of combinations exceeded the yield of their respective tester lines, whereas about 75% and 25% of combinations surpassed two elite Chinese cultivars, respectively. This strong heterosis was further confirmed by reevaluating 2 out of the 129 combinations in a successive year and by surveying hybrids between 20 lines of the new type of B. napus in BC1F5 and its parental B. napus in two locations. Some DNA segments from B. rapa were identified with significant effects on seed yield and yield components of the new type of B. napus in BC1F5 and intersubgenomic hybrids in positive or negative direction. It seems that the genomic components introgressed from B. rapa contributed to improvement of seed yield of rapeseed. 相似文献
994.
Shuli Liang Chengjuan Zou Ying Lin Xuanwei Zhang Yanrui Ye 《Biotechnology letters》2013,35(11):1865-1871
The available promoters in the Pichia pastoris expression platform are still limited. We selected and identified a novel strong constitutive promoter, P GCW14 , and tested its promoter activity using enhanced green fluorescent protein (EGFP) as a reporter. Potential promoter regions of P GCW14 were cloned upstream of the EGFP gene and promoter activity was analyzed by measuring fluorescence intensity. P GCW14 exhibited significantly stronger promoter activity than the classic strong constitutive promoters P TEF1 and P GAP under various carbon sources, suggesting that P GCW14 is a strong and constitutive promoter. Hence, P GCW14 can be used as a promoter for high-level expression of heterologous proteins. 相似文献
995.
Journal of Applied Phycology - Atmospheric CO2 concentration is predicted to nearly double by the end of this century. There are a large number of reports on the effects of elevated atmospheric CO2... 相似文献
996.
MICA polymorphism in South American Indians 总被引:3,自引:0,他引:3
Zhang Y Lazaro AM Zou Y Lavingia B Moraes EM Moraes RJ Stastny P 《Immunogenetics》2002,53(10-11):900-906
We have studied the MICA alleles of 196 unrelated subjects from three South American Indian tribes (Toba, Wichi and Terena). They are members of isolated tribes located in the Gran Chaco area in northeastern Argentina and in Mato Grosso do Sul in South Central Brazil. Of 55 previously known alleles, nine were observed in South American Indians, compared with 16 that were found in North American Caucasians, suggesting a more restricted allelic distribution of MICA in these tribes. In South American Indians, MICA*00201 was the most frequent allele, with a gene frequency of 33% in Toba, 47% in Wichi and 44% in Terena. MICA*00201, MICA*027 (external domain sequence like MICA*008/TM allele A5) and MICA*010 accounted for more than 90% of all the MICA genes in South American Indians. In North American Caucasians, MICA*00801 (*008/A5.1) accounted for 42% of the genes and was the most common allele. We observed a high degree of linkage disequilibrium between certain alleles of MICA and of HLA-B in the South American Indian populations. Phylogenetic trees constructed using gene frequencies of the transmembrane short tandem repeats in the populations reported here, and in other populations taken from published reports, suggest that South American Indians are more closely related to Asians than to Europeans. 相似文献
997.
Jia Chunhua Yu Xiaojing Zhang Min Liu Zhiguang Zou Peng Ma Jun Xu Yachun 《Journal of Plant Growth Regulation》2020,39(2):631-640
Journal of Plant Growth Regulation - The growth and development of cold-season plants are susceptible to high temperature. Melatonin is a plant growth regulator with potential to improve plant... 相似文献
998.
Zeng L Ji X Zhang Y Miao X Zou C Lang H Zhang J Li Y Wang X Qi H Ren D Guo G 《Electromagnetic biology and medicine》2011,30(4):205-218
Male Sprague Dawley rats were exposed to EMP irradiation of 100?kV/m peak-to-peak e-field intensity and different numbers of pulses. Rat sperm samples were prepared for analysis of sperm qualities; Testes were assessed by transmission electron microscopy and serum hormone concentrations were examined by radioimmunoassay; Enzymatic activities of Total-superoxide dismutase(T-SOD) and manganese-superoxide dismutase (MnSOD), the mRNA levels of MnSOD and cuprozinc-superoxide dismutase (CuZnSOD), and the density of malondialdehyde (MDA) were also determined. EMP irradiation did not affect spermatozoon morphology, micronucleus formation rate, sperm number or viability, but the acrosin reaction rate decreased at 24?h and 48?h and recovered by 72?h after irradiation as compared to the controls. The ultrastructure of rat testis displayed more serious damage at 24?h than at other time points (6?h, 12?h, 48?h). Serum levels of luteotrophic hormone (LH) and testosterone (T) were elevated in irradiated rats as compared to controls. After irradiation, enzymatic activities of T-SOD and MnSOD were reduced by 24?h, consistent with the changes observed in MnSOD mRNA expression; MDA content increased at 6?h in turn. These studies have quantified the morphological damage and dysfunction in the rat reproductive system induced by EMP. The mechanism of EMP induced damage may be associated with the inhibition of MnSOD expression. 相似文献
999.
采用酶抑制剂法和前体喂养试验法初步研究了结构新颖的活性蒽醌化合物1403C的合成途径.研究表明,甲羟戊酸合成途径的关键酶抑制剂邻氨基苯甲酸、柠檬酸三钠对单位菌体1403C产量影响比较小;莽草酸途径关键酶氨基苯甲酸合成酶的抑制剂三甲胺在低浓度时(3、6 mmol/L)对单位菌体1403C产量没有影响,而高浓度(12 mmol/L)时由于较大程度改变发酵液pH而降低了单位菌体1403C产量;莽草酸途径中间产物莽草酸的添加对单位菌体1403C产量没有明显的影响;添加聚酮合成途径聚酮合酶的专一性抑制剂碘乙酰胺对1403C的合成产生强烈的抑制,抑制程度达94.2%;添加丙二酸对1403C的合成有较大的促进作用,单位菌体1403C产量最大增加了59.2%.乙酸钠和丙二酸混合比例为1∶ 4时对单位菌体1403C产量具有最大促进作用,最大提高量为102.7%.由此推断Halorosellinia sp.(No.1403)可能通过聚酮途径合成1403C. 相似文献
1000.
Lianzheng Yu Chao Jiang Jun Na Ning Li Wenli Diao Yuan Gu Li Zhao Yan Zou Ying Chen Li Liu Huijuan Mu Yunyong Liu Liya Yu Xiaoli Yang Guowei Pan 《PloS one》2013,8(4)