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991.
利用DAD1反义片段转化创建菜薹可调控雄性不育材料 总被引:1,自引:0,他引:1
菜薹因为没有好的雄性不育材料或自交不亲和系,至今尚无一代杂种用于生产,根据拟南芥及白菜型油菜的花药不开裂基因DAD1的保守序列设计引物,扩增菜薹的DAD1基因片段(DAD1F),构建反义DAD1F植物表达载体,用农杆菌介导法转化菜薹,对转基因植株进行分子检测,鉴定其雄性不育性并进行育性恢复试验.克隆得到的菜薹的DAD1基因片段大小为678 bp,命名为BrcpDAD1F,其序列与拟南芥和白菜型油菜的DAD1高度同源,同源率分别为88%和99%;共得到了12株转基因植株,有6株在转录水平上得到表达,表现为雄性不育,花器官畸形,花粉活力低,萌发率不到10%,且开花后不能结角果或结空角果,或者得到极少种子但种子不萌发;用对照的花粉给转基因植株授粉可使其正常结实.以500 μmol·L-1茉莉酸甲酯处理可使其雄性不育得到恢复,花粉可以在柱头和培养基上萌发,具有受精能力。T1代可育株与不育株的比例都呈1:3分离, T2代不同株系的育性分离比例不同,有些株系继续呈1:3的分离,有些株系全是可育株或全是不育株,说明反义抑制呈单基因稳定遗传。 相似文献
992.
月季RcHSP1718为编码小分子热激蛋白基因, Southern检测其在月季基因组中为多拷贝存在。38 ℃/3 h热激处理后, 该基因在耐热月季品种‘曼海姆宫殿’ ( Schloss Mannieim) 、‘彩虹’ (Radio) 、‘赌城’ (Las Vegas) 、‘梅郎随想曲’ (Caprice de Meiland) 、‘小女孩’ ( Girl) 中强表达, 而在不耐热品种‘新十全’ (Kordes’Perfecta) 、‘绯扇’ (Hiogi) 、‘莱茵黄金’ ( Pfalzer Gold) 中弱表达或不表达, 表明该基因与月季耐热性关系密切。为确定月季RcHSP1718基因功能, 将其转化E.coli BL21, 结果表明重组菌株能正常诱导表达包含RcHSP17.8的融合蛋白, 并因此提高了重组菌株对高温、低温、高盐、高pH、重金属、氧化等非生物胁迫的耐性, 表明RcHSP17.8参与了上述非生物胁迫的响应。 相似文献
993.
994.
AIM:To investigate the key molecular mechanism of inflammatory response in alveolar epithelial cells induced by nontypeable haemophilus influenzae (NTHi). METHODS: A549 cells were co-cultured with NTHi (multiplicity of infection, MOI: 10) and harvested 15 min and 30 min after stimulation. The phosphorylation of p38 mitogen activated protein kinase (p38 MAPK) in A549 cells was detected by Western blotting. The intracellular expression of nuclear factor-κB (NF-κB) p65 was examined by flow cytometry 4 h after stimulation. A549 cells were preincubated with p38 inhibitor (SB203580) or NF-κB inhibitor (PDTC) for 1 h and then stimulated with NTHi for 24 h. The level of interleukin 8 (IL-8) in the supernatants was determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: The phosphorylation of p38 MAPK was rapidly induced by NTHi stimulation. The expression of NF-κB p65 in A549 cells after NTHi stimulation was significantly up-regulated compared with control group (P<0.05). The level of IL-8 in the supernatants was increased 24 h after bacterial stimulation compared with control group (P<0.05). Blockage of p38 MAPK or NF-κB remarkably decreased IL-8 secretion in A549 cells (P<0.05). CONCLUSION:NTHi induces inflammatory response in alveolar epithelial cells in a p38 MAPK and NF-κB dependent manner. 相似文献
995.
AIM: To study the changes of zinc transporter gene expression in A-549 cell line exposed to ZnCl2 and N,N,N’,N’-tetrakis 2-pyridylmethyl ethylenediamine (TPEN).METHODS: Human lung cancer cell line A-549 was exposed to different concentrations of ZnCl2 (0, 50, 100, 150, 200 μmol/L) and TPEN (0, 5, 10, 15, 20 μmol/L), respectively. Twelve hours later, the cell viability was measured by MTT (methyl thiazolyl tetrazolium) and levels of zinc transporter mRNA was detected by RT-PCR. Zinquin was used to estimate the intracellular zinc concentrations.RESULTS: A-549 cell viability rate was significantly decreased when exposed to ZnCl2 at concentrations of 150 and 200 μmol/L, and to TPEN. The intracellular zinc concentration was significantly increased when exposed to ZnCl2 and decreased when exposed to TPEN. Zinc transporter (ZnT-1) mRNA level was increased along with the increase in the concentration of ZnCl2 but decreased when exposed to TPEN. The expressions of ZIP-1 and ZIP-10 (Zrt-and Irt-like protein) were increased along with the increase in the concentration of TPEN but decreased when exposed to ZnCl2.CONCLUSION: ZnT-1 expression is induced by zinc supplement. ZIP-1 and ZIP-10 expressions are induced by zinc deficiency and repressed by zinc supplement. 相似文献
996.
AIM: To investigate adrenomedullin gene transfection enhances the therapeutic effects of homogeneous transplantation of bone marrow mesenchymal stem cells (MSCs) on cardiac function and ventricle remodeling in acute myocardial infarction rats. METHODS: MSCs were isolated and expanded using the preplating method. The infection efficiency of adenovirus vector to MSCs was tested by X-gal staining. Ad-ADM expression in MSCs and its secretion in culture medium were measured by ELISA. The left anterior descending branch of rats was ligated to establish a myocardial infarction model. The MSCs were labeled by DAPI, and were directly implanted into the acute infarct site via focal injection. Four weeks later, cardiac function was evaluated using physiological recorder. Hearts were harvested and sliced to be analyzed by immunohistochemistry (factor Ⅷ and ADM) and the DAPI-labeled cells were identified. Sirius red staining was used to identify interstitial collagen on slides. Analysis of collagen type I and III was performed using a polarized filter on sections stained for collagen with Sirius red, and the ratio of collagen type I and III were detected. RESULTS: With X-gal staining, MSCs were effectively transfected by adenovirus in vitro. The transfection efficiency showed the dose-effect relationship with multiplicities of infection (MOI). When MOI was 150, the infection efficiency was 95.4%. The expression of ADM was traced in culture medium and expressed in the time-dependent manner. A maximum production of ADM was observed at 7 d after infection [(26.53±1.42) ng/L vs (1.34±0.08) ng/L, P<0.05], and ADM secretion reduced to normal level at 15 d [(2.20±1.44) ng/L vs (1.52±0.33) ng/L, P>0.05]. DAPI-labeled MSCs transplantation was found in the hearts of the recipients. Immunohistochemical studies demonstrated that intense immunostaining for ADM was higher in Ad-ADM plus MSCs group, compared to other groups. Compared with control, MSCs transplantation significantly increased capillary density in infarct area (P<0.01). A combination of Ad-ADM trensfection and MSCs transplantation demonstrated a further increase in capillary density compared with Ad-ADM or MSCs alone. MSCs transplantation decreased the ratio of collagen type I and III, obviously improved the left ventricular functions. Furthermore the combination treatment resulted in further decrease in the ratio of collagen type I and III, and significantly improved the left ventricular functions. CONCLUSION: Ad-ADM transfection enhances the angiogenic potency of MSCs transplantation and decreases the ratio of collagen type I and III through increasing ADM expression in infarct area, thus contributes to reverse the ventricular remodeling and improves the cardiac function. 相似文献
997.
998.
LIANG Jun-qing SUN Shi-ran WU Yi-ling GAO Wei-juan XU Hai-bo ZHANG Qiu-yan WANG Hai-rong WEI Cong CHEN Jian-xin CHEN Jing 《园艺学报》2009,25(6):1064-1069
AIM: To investigate the mechanisms and relationship among endothelial dysfunction, renin-angiotensin-aldosterone system (RAAS) and family of interleukins under the condition of excessive fatigue, by using the rats with fatigue stress. METHODS: Healthy male Wistar rats were randomly divided into control group, homocysteine (HCY) group, fatigue stress group, renshen group, shuangshen group and tongxinluo group. Radioimmunoassay was carried out to detect plasma renin activity (PRA), angiotensin II (AngⅡ), aldosterone (ALD), endothelin (ET), thromboxane-2 (TXA2), prostaglandin I2 (PGI2) in plasma and interleukin-1β, 2, 6, 10 (IL -1β, IL -2, IL -6) in sera. ELISA was used to detect NE and IL -10. The content of nitric oxide (NO) in sera was also detected. The bioinformatical analysis was used to determine the relationship between RAAS and endothelial dysfunction. RESULTS: Compared with control group, the levels of ET-1 and TXA2 in fatigue stress group were significantly increased (P<0.01, P<0.05), but the content of PGI2 and NO was significantly decreased (P<0.01, P<0.01). Compared with control group, the renin activity in plasma of animals in fatigue stress group was significantly decreased (P<0.01), the AngⅡ, IL -1β, IL -6 level was significantly increased compared with the control group (P<0.01, P<0.01), and was significantly increased compared with the HCY group (P<0.05, P<0.01, P<0.01). The NE level showed the tendency of decrease in different degree. After the intervention of three kinds of herbs to dredge collaterals, the ET-1, AngⅡ, IL -1β, IL-6 level in plasma was decreased in different degree (P<0.05, P<0.01, P<0.01), and at the same time, the contents of NO and NE level were significantly increased (P<0.05). The ALD level in tongxinluo groups was apparently higher than that in control group and the fatigue stress group (P<0.05). The bioinformatics analysis showed that Ang II and ET, IL-1; PGI2 and ALD; NO and ALD composed of three subsystems and interrelated according to the principle of optimality of complex system, and gradual change regulation was also observed in fatigue stress group. However, in control group, HCY group and tongxinluo group, the same interrelation among subsystems was not existed. CONCLUSION: In a state of long-term excessive fatigue, vascular endothelial dysfunction may be induced, and is related with renin-angiotensin-aldosterone system imbalance and serious turbulence of the autonomic dysfunction. Herbs to dredge collaterals could improve it significantly. The results suggest that bearing excessive fatigue and pressure in long-term may be the potential risk factors to induce vascular endothelial dysfunction and further result in cardio-cerebro vascular diseases, Tongluo therapy may be one of the useful ways to prevent such diseases. 相似文献
999.
1000.
XIAO Xiao-ping LI Yue-qin XU Bin LI Hong-jian ZHANG Xin ZHOU Tian-hong ZOU Yi 《园艺学报》2009,25(7):1254-1261
AIM: To study the anti-proliferation effect of overexpressed SSTR2 in experimental cancer with different profiles of endogenous SSTRs expressions and the possible signaling pathways involved. METHODS: In the first experiment, the growth of the tumor xenografts of the inoculated capan-2 cells and A549 cells overexpressing SSTR2 or LacZ was investigated in nude mice. In the second experiment, the adenoviral vector expressing SSTR2 were introduced into experimental capan-2 xenografts by intratumoral injection. The growth inhibition of these experiment tumors was observed and the potential influences on different signaling pathways were analyzed by immunoassays. RESULTS: Overexpression of SSTR2 inhibited the growth of tumors with different profiles of endogenous SSTRs, including experimental capan-2 xenografts that had endogenous SSTR2 expression. Overexpression significantly affected a number of components in apoptotic pathway, MAPK pathway and angiogenesis. CONCLUSION: SSTR2 is a promising candidate for gene therapy in a wide spectrum of cancers. 相似文献