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101.
YAN Jin-hai WANG Zhi-qiang HAN Xi-qun CHEN Shao-hong ZHOU Xin-hua JIAN Wen-jing GE Juan ZHAO Tong 《园艺学报》2014,30(2):226-232
AIM:To investigate the mechanism that over-expression of hsa-miR-150 induces the re-differentiation of diffuse large B-cell lymphoma cell line OCI-Ly10. METHODS:The expression level of hsa-miR-150 in CD19+B and OCI-Ly10 cell lines was detected by real-time PCR. The expression level of c-Myb was detected by Western blotting and immunofluorescence cytochemistry methods. Lentiviral supernatant containing recombinant plasmids was transfected into OCI-Ly10 cells by LipofectamineTM 2000 and named Ly10-control and Ly10-miR-150. The biological functions of the 2 cell sublines were identified by MTT assay. The cell cycle and apoptotic rates were detected by flow cytometry. The expression levels of B-lymphocyte differentiation-related genes and c-myb in Ly10-control and Ly10-miR-150 cells were detected by real-time PCR and Western blotting. When c-myb was interfered in by interference fragment in OCI-Ly10 cells, the interference efficiency and the expression levels of BCL6 and PRDM1 were detected by real-time PCR and Western blotting. RESULTS:The expression level of hsa-miR-150 in CD19+ B cells was significantly higher than that in OCI-Ly10 cells. The expression level of c-Myb in OCI-Ly10 cells was higher than that in CD19+ B cells. The expression levels of B-lymphocyte differentiation-related genes were changed significantly in OCI-Ly10 cells after transfected with hsa-miR-150. The expression levels of PAX5, BCL6 and c-Myb in Ly10-miR-150 cells were lower than those in Ly10-control cells, but the expression levels of IRF4, PRDM1 and XBP1 were higher than those in Ly10-control cells. The expression level of BCL6 was lower and PRDM1 was higher after interference. CONCLUSION:Hsa-miR-150 plays a significant role in inhibiting proliferation and inducing apoptosis of OCI-Ly10 cells. The mechanism that over-expression of hsa-miR-150 induces OCI-Ly10 cell differentiation toward terminal B cells may be related to the down-regulation of c-myb. 相似文献
102.
AIM: To observe the effects of Arid2gene on cell proliferation and cell cycle by interference of endogenous Arid2 expression in hepatoma cells. METHODS: Three pairs of shRNA targeting Arid2gene were cloned into a shuttle vector to construct recombinant adenovirus plasmids. HEK293 cells were transfected with the recombinant adenovirus plasmids. After several rounds of the package and amplification, the high-titer adenoviruses AdsiArid2-1~3 were obtained. To verify the inhibitory effects of AdsiArid2 adenoviruses, Western blotting was used to detect the endogenous Arid2 protien expression in SMMC-7721 cells. Cell growth and cell cycle analysis were carried out by MTS assay and flow cytometry. RESULTS: High- titer recombinant adenovirus of siArid2 were successfully obtained, and named AdsiArid2-1~3, among which the AdsiArid2-3 had the best inhibitory effects. MTS assay showed that the absorbance values at 490 nm were increased at 72 h and 96 h after transduction compared with the mock and Adsicontrol groups. These data indicated that knockdown of Arid2 promoted the proliferation rate of SMMC-7721 cells(P<0.05). Moreover, the flow cytometry analysis revealed that the G1-phase distribution at 72 h in AdsiArid2 group was lower than that in mock group and Adsicontrol group. In contrast, the S-phase distribution in AdsiArid2 group was much higher than that in mock group and Adsicontrol group. CONCLUSION: The recombinant plasmids and recombinant adenovirus were successfully constructed. shRNA-mediated knockdown of Arid2 promotes the proliferation and the transition from G1 phase to S phase of hepatoma cells. 相似文献
103.
104.
黑龙江大豆栽培品种和新品系对疫霉病抗性评价及抗病基因分析 总被引:1,自引:1,他引:0
由Phytophthora sojae引致的大豆疫霉病是黑龙江大豆产区的重要病害之一。该病已在我国大豆一些主要栽培区发生,并引起较大危害。培育和种植抗疫霉病品种是控制该病最有效的方法。本研究旨在筛选黑龙江地区的大豆疫霉病抗病品种和品系,为病害的防治和抗病品种的合理布局提供参考。在大豆苗期用下胚轴伤口接种方法对126个栽培大豆品种和135份大豆品系进行接种,鉴定其对黑龙江大豆主要疫霉病菌株(8个)的抗性。鉴定结果表明:有72个品种抗4个以上菌株,占鉴定品种的57.1%;84份品系抗4个以上菌株,占鉴定品系的62.2%。对品种的基因分析表明,有30个大豆品种含有抗病基因,其中有10个品种分别含有Rps1k、 Rps3a、Rps1c三个主要基因。 相似文献
105.
106.
Uterine biology in pigs and sheep 总被引:2,自引:0,他引:2
FW Bazer G Song J Kim KA Dunlap MC Satterfield GA Johnson RC Burghardt G Wu 《畜牧与生物技术杂志(英文版)》2012,3(1):23-21
ABSTRACT: There is a dialogue between the developing conceptus (embryo-fetus and associated placental membranes) and maternal uterus which must be established during the peri-implantation period for pregnancy recognition signaling, implantation, regulation of gene expression by uterine epithelial and stromal cells, placentation and exchange of nutrients and gases. The uterus provide a microenvironment in which molecules secreted by uterine epithelia or transported into the uterine lumen represent histotroph required for growth and development of the conceptus and receptivity of the uterus to implantation. Pregnancy recognition signaling mechanisms sustain the functional lifespan of the corpora lutea (CL) which produce progesterone, the hormone of pregnancy essential for uterine functions that support implantation and placentation required for a successful outcome of pregnancy. It is within the peri-implantation period that most embryonic deaths occur due to deficiencies attributed to uterine functions or failure of the conceptus to develop appropriately, signal pregnancy recognition and/or undergo implantation and placentation. With proper placentation, the fetal fluids and fetal membranes each have unique functions to ensure hematotrophic and histotrophic nutrition in support of growth and development of the fetus. The endocrine status of the pregnant female and her nutritional status are critical for successful establishment and maintenance of pregnancy. This review addresses the complexity of key mechanisms that are characteristic of successful reproduction in sheep and pigs and gaps in knowledge that must be the subject of research in order to enhance fertility and reproductive health of livestock species. 相似文献
107.
23个小麦抗叶锈病近等基因系SRAP多态性 总被引:6,自引:0,他引:6
【目的】分析以Thatcher为遗传背景的小麦抗叶锈病近等基因系的遗传多样性,探讨SRAP技术在小麦抗叶锈病基因标记及基因克隆研究中应用的可行性。【方法】采用SRAP(sequence-related amplified polymorphism)技术对23个以Thatcher为遗传背景的小麦抗叶锈病近等基因系和感病对照Thatcher进行分析。【结果】从128对引物中筛选得到41对具有多态性引物,每个引物组合产生6~41个多态性条带,共产生537个多态性条带,多态性条带率达49.5%,平均每个引物组合产生13.1个多态性条带;每个引物组合产生1~13个特异性条带,共产生115个特异性条带,特异性条带率为10.6%,平均每个引物组合产生2.8个特异性条带。聚类分析将23个小麦抗叶锈病近等基因系和Thatcher在相似系数0.72处分为A、B两大类,其中96%的个体归入B类。B类又分为Ⅰ、Ⅱ两个亚类,95%的个体聚在第Ⅱ亚类。第Ⅱ亚类在相似系数为0.785附近分为4小类。【结论】23个小麦抗叶锈病近等基因系间存在一定的差异。SRAP技术是一种简单有效的分子标记系统,可在小麦叶锈病抗病基因的研究中应用。 相似文献
108.
PTEN gene, identified in 1997 and named after the separation, was a new candidate tumor suppressor gene. The mutations of PTEN gene, loss of heterozygosity in human tumors are prevalent, such as malignant glioma, endometrial cancer, prostate cancer, breast cancer, etc. The mutation frequency of PTEN is equivalent to p53. As an important functional element and a tumor suppressor gene, most scholars agree that PTEN gene is as important as p53. At present, studies on the PTEN gene mainly concentrated in the tumor area, its functions in the cardiovascular system are few reports. This article reviews the investigation of PTEN gene in the cardiovascular system. 相似文献
109.
本文简要概述了主要经济双壳贝类性别分化分子机制研究进展,介绍国内外研究性别分化和性别决定的代表性双壳贝类物种及主要研究成果,主要涉及牡蛎科(Ostreidae)、扇贝科(Pectinidae)、珍珠贝科(Pteriidae)等常见的经济物种,分子层面涵盖了核酸、蛋白质和激素等,通过综述这些物种相关研究的现状,展望双壳贝类性别分化研究的发展趋势,以期加深对双壳贝类性别分化和性腺发育的认识,为解析虾夷扇贝(Patinopecten yessoensis)及其他双壳贝类性别分化分子机制研究理清思路。 相似文献
110.
研究了外源基因对小单孢菌40027菌株产生抗生素水平的影响。结果表明:整合了质粒pSET152和质粒pHZ1904的小单孢菌40027菌株比原始菌株产生福堤霉素A的产量低,在产素时间上缩短;整合了质粒pSET152和pHZ1904小单孢菌40027菌株之间在产素水平和产素时间上没有显著差异。表明整合了质粒pSET152和pHZ1904的小单孢菌40027菌株与原始菌株在产素水平和产素时间上的差异是由质粒pSET152造成的,dnd基因簇对小单孢菌40027菌株的产素水平和产素时间没有影响。 相似文献