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文章采用基因定点突变和报告基因技术作A/T富集区启动子鉴定和转录调控分析,研究鸡miR-17-92基因簇上游A/T富集区是否具有启动子活性。PromPredict预测分析提示miR-17-92基因簇上游-388~-444 bp处可能是启动子区域。转录因子结合位点分析发现,A/T富集区存在3个E2F1潜在结合位点,分别位于miR-17-92基因簇上游-1 273 bp(结合位点1)、-1 186 bp(结合位点2)和-753 bp(结合位点3)处。报告基因活性分析发现,鸡miR-17-92基因簇上游A/T富集区具有启动子活性,其中miR-17-92基因簇上游-440/-1区域启动子活性最强。共转染分析显示,转录因子E2F1极显著抑制该A/T富集区启动子活性(P<0.01);进一步定点突变分析表明E2F1通过E2F1结合位点1和2抑制A/T富集区启动子活性。报告基因分析发现,与对A/T富集区启动子作用不同,E2F1促进miR-17-92基因簇宿主基因(MIR17HG)启动子活性。文章首次发现鸡miR-17-92基因簇上游存在一个新的转录调控区,对揭示鸡miR-17-92基因簇转录调控具有重要意义。 相似文献
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QU Yi-ming SHAO Gao-hai ZHANG Ming-hua LI Bo ZHU Feng-chen HE Chao CAO Chun-feng ZHAO Bo 《园艺学报》2020,36(6):1089-1095
AIM To explore the effect of platelet-rich plasma (PRP) on rabbit osteoarthritis and its possible mechanism. METHODS The rabbits with knee osteoarthritis were prepared and then divided into model group, sodium hyaluronate (SH) group and PRP group, and another sham operation group was set up, with 6 rabbits in each group. The gross morphological changes of rabbit cartilage were observed. HE staining was used to evaluate the pathomorphological changes of the cartilage. TUNEL staining was used to detect the apoptosis of chondrocytes. The expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)/interleukin-1β (IL-1β) signaling pathway-related molecules was observed by immunohistochemical staining, and the protein levels of caspase-3, Bcl-2 and Bax were determined by Western blot. Chondrocytes were isolated and processed according to grouping, and the NLRP3 and IL-1β levels of the cells were measured by ELISA. RESULTS Compared with sham operation group, Pelletier score, Mankin score, chondrocyte apoptotic rate, the positive protein expression rates of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in model group were increased significantly (P <0.05), while the protein expression of Bcl-2 was decreased significantly (P <0.05). Compared with model group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in SH group and PRP group were decreased significantly (P <0.05), while the protein expression of Bcl-2 was increased significantly (P <0.05). In PRP group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax were lower than those in SH group, while the protein expression of Bcl-2 was higher than that in SH group (P <0.05). Compared with control group, the expression of NL?RP3 and IL-1β in MCC950 (NLRP3 ihibitor) group were significantly reduced (P <0.05), the expression of NLRP3 in eucalyptol (IL-1β inhibitor) group was not significantly changed (P >0.05), and the expression of IL-1β was significantly reduced (P <0.05). CONCLUSION Platelet-rich plasma promotes the repair of cartilage in osteoarthritis rabbits, which has better effect than SH. The mechanism may be related to the inhibition of NLRP3/IL-1β pathway and the reduction of chondrocyte apoptosis. 相似文献
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ZHAO Xue-rong WANG Jian-ping XIAO Li-jun XU Qian ZHAO En-hong ZHENG Xin ZHENG Hua-chuan ZHAO Shuang 《园艺学报》2015,31(1):98-103
AIM: To investigate the effects of 17-AAG on apoptosis and cell cycle of HCT-15 cells and to clarify the related mechanisms. METHODS: MTT method was employed to evaluate the inhibitory effects of 17-AAG with Aifferent time and different doses on the proliferation of HCT-15 cells. The cells were stained with Annexin V-FITC/propidiumiodide and measured by flow cytometry. The expression of STAT3, cyclin D1, Cyt C, caspase 9 and caspase 3 at mRNA and protein levels was determined by RT-PCR and Western blotting. RESULTS: Treatment with 17-AAG at concentration of 1.25~20 mg/L for 24 h and 48 h significantly inhibited the activity of HCT-15 cells at both time-and concentration-dependent manners. Treatment with 17-AAG at concentrations of 0.425, 0.85 and 1.7 mg/L for 48 h significantly induced apoptosis and cell cycle arrest of HCT-15 cells. The exposure of 17-AAG at concentrations of 0.425, 0.85 and 1.7 mg/L for 48 h to the HCT-15 cells significantly down-regulated the expression of STAT3 and cyclin D1 at mRNA and protein levels, but up-regulated Cyt C, caspase 9 and caspase 3 mRNA and protein in a concentration-dependent manner. CONCLUSION: 17-AAG inhibits the cell activity, induces apoptosis and G1 arrest by down-regulating the expression of cyclin D1, and promoting the mitochondria apoptosis through STAT3 pathway. 相似文献
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CUI Yu GUAN Li-bin LI Xiao-xu YANG Cheng-zhong TAN Xiao-ling GAO Yu-qi HUANG Jian 《园艺学报》2015,31(2):250-255
AIM: To investigate the changes of retinoid-related orphan receptor γt(RORγt) mRNA and interleukin-17(IL-17) protein in the lung tissue under hypobaric hypoxia, and the relationship between Th17 cells and hypoxic pulmonary vascular reconstruction. METHODS: Male BALB/c mice(n=50) were randomly divided into control group and 3 d, 7 d, 14 d and 28 d hypobaric hypoxia groups. The mice in hypobaric hypoxia groups were housed in a hypobaric hypoxia chamber(simulated altitude of 6 000 m) for 3 d, 7 d, 14 d or 28 d. The mice in control group were housed in normal pressure and oxygen environment. The hemodynamic data were recorded by cardiac catheterization. The hypertrophy of right ventricle was evaluated by the ratio of weight of the right ventricle to the weight of the left ventricle plus interventri-cular septum, and the right ventricular weight over body weight. The spleen was collected and the proportions of the Th17(CD4+IL-17+RORγt+) cells were detected by flow cytometry. The serum levels of IL-4, IL-6 and IL-17 and the change of IL-17 in the lung tissue were measured by ELISA. The mRNA expression of RORγt in the spleen and lung tissues was measured by RT-qPCR. RESULTS: Compared with control group, the mouse right ventricular systolic pressure, the hypertrophy index of right ventricle and the serum IL-17 level were significantly elevated in hypoxia groups, which was consistent with the results of flow cytometry. The mRNA expression of RORγt in the lung tissue was also significantly increased in 7 d, 14 d and 28 d hypoxia groups. The expression of IL-17 in the lung tissue was significantly increased in 14 d and 28 d hypoxia groups. CONCLUSION: Hypoxia promotes differentiation of Th0 cells to Th17 cells in the spleen. The Th17 cells infiltrated in the lung tissue under hypobarric hypoxia are involved in pulmonary vascular reconstruction. 相似文献
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以拟南芥去甲基化转移酶基因DME1为目的基因,采用酶切、连接和重组反应的方法构建了以17-β-雌二醇为诱导剂的植物表达载体p ER8-DME1。将其转入农杆菌LBA4404菌株中,通过烟草瞬时表达技术,对该载体的诱导表达特性进行了研究。q PCR结果表明,较低浓度的17-β-雌二醇处理能够有效调控p ER8-DME1中目的基因的表达,诱导处理后目的基因表达量逐渐升高,在12 h后达到最高,之后缓慢下降。该载体的成功构建为深入研究DNA去甲基化与植物的生殖发育调控奠定了基础。 相似文献
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Efficacy of 17 α‐methyl testosterone and letrozole on sex reversal of protogynous grouper,Epinephelus tauvina (Forskal, 1775) and spawning performance of sex‐reversed males 下载免费PDF全文
Ritesh Ranjan Biji Xavier Biswajit Dash Loveson L Edward Relangi D Suresh Pilli Suresh Kumar 《Aquaculture Research》2015,46(9):2065-2072
This study aimed to test the efficacy of 17 α‐methyl testosterone (17 α‐MT) alone and in combination with letrozole, an aromatase inhibitor, for the induction of sex reversal in protogynous greasy grouper, Epinephelus tauvina. Further, the long‐lasting effects of these treatments and spawning performance of sex‐reversed males were also investigated. Greasy grouper with oocytes in the perinucleolus stage were implanted with 5 mg 17 α‐MT kg?1 body weight (T1), 5 mg 17 α‐MT and 0.2 mg letrozole kg?1 body weight (T2) and 5 mg 17 α‐MT with 0.4 mg letrozole kg?1 body weight (T3) and no androgens/enzyme inhibitor implanted (C). The 17 α‐MT alone and in combination of letrozole‐induced sex reversal in greasy grouper, whereas untreated control fish (C) showed normal ovarian development. However, T2 and T3 group showed 100% sex reversal and completion of spermatogenesis up to functional male phase in 2 and 3 months, respectively, whereas T1 group resulted in only 66.67% functional male with motile spermatozoa after 4 months. Sex‐reversed males successfully fertilized the eggs during induced spawning. There were significant differences on fertilization and hatching rates between T2 group (79.00 ± 4.36%; 77.67 ± 2.87%, respectively) and T1 group (57.67 ± 3.17%; 63.87 ± 2.91%, respectively). The result suggested that 17 α‐MT (5.0 mg kg?1 BW) in combination with letrozole (0.2 mg kg?1 BW) has the potential to produce 100% sex‐reversed male in short period in greasy grouper, which might greatly help in seed production of greasy grouper. 相似文献
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为揭示类固醇生成相关基因CYP11A1、CYP17A1、CYP19A1在绵羊多羔繁殖中的作用,以不同繁殖力小尾寒羊为研究对象,采用实时荧光定量PCR技术检测CYP11A1、CYP17A1、CYP19A1基因在小尾寒羊大脑、小脑、下丘脑、垂体、子宫、卵巢、输卵管中的表达。结果表明:CYP11A1基因主要在小尾寒羊卵巢、输卵管、子宫内表达;CYP11A1基因在单羔小尾寒羊卵巢的表达极显著低于多羔群体(P0.01),在子宫的表达量极显著高于多羔群体(P0.01);CYP17A1基因主要在小尾寒羊卵巢、输卵管、下丘脑表达;CYP17A1基因在多羔小尾寒羊群体下丘脑、子宫的表达量显著低于单羔群体(P0.05)。CYP19A1基因主要在小尾寒羊卵巢、下丘脑表达。本究结果提示CYP11A1、CYP17A1基因可能参与小尾寒羊多羔性状的调控。 相似文献
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