微小RNA在胃癌中的研究

胃癌是世界最常见的恶性肿瘤之一，寻找理想的胃癌早期诊断的标记物和有效治疗靶点，对改善胃癌患者的预后有着重要的意义。     

克隆颜色鉴定结合5-氟乳清酸负筛提高三杂交系统筛库效率

酵母三杂交系统是新近发展起来的一个分析ＲＮＡ结合蛋白的有力工具，然而在利用该系统筛库过程中，常会遇到大量假阳克隆，将克隆颜色鉴定与５－氟乳清酸负性筛选相结合，运用到酵母杂交系统的筛库过程中，极大地提高了筛库的效率和对假阳性克隆的鉴别，并已实现了对重要的ＲＮＡ结合蛋白的筛选，这一改进将大大方便该系统在分析ＲＮＡ与蛋白的相互作用中的运用。     

Noncoding RNAs: Different roles in tumorigenesis

A major portion of the mammalian genome is transcribed to produce large numbers of noncoding RNAs(ncRNAs).During the past decade,the discovery of small RNAs,including the microRNAs(miRNA) and small interfering RNAs(siRNA),has led to important advances in biology.The breadth of the ncRNA field of study has substantially expanded and many recent results have revealed a range of functions that can be attributed to the miRNAs and other ncRNAs.For example,H19 RNA,HOTAIR RNA,transcribed ultraconserved regions(T-UCRs),natural antisense RNA,transfer RNA and mitochondrial noncoding RNA have been suggested to play important roles in cancers and other diseases as well as in diverse cellular processes.In this review,we focus on the current status of several classes of ncRNAs associated with cancer with the emphasis on those that are not microRNAs.     

mRNA二级结构对重组人白血病抑制因子（rhLIF）在大肠杆菌中表达 …

真细菌中翻译起始效率通常是由翻译起始位点两侧的ｍＲＮＡ区域二级结构的稳定性决定的。这种稳定性与该区域ＲＮＡ二级结构的发生自由能相对应。重组人白细胞病抑制因子为具有诱导白血病细胞分化，调节骨组织的生长代谢，维持胚胎干细胞的基本特征，促进神经元的分化等广泛生物学活性的细胞因子。     

MiR-205 inhibits the invasion and migration of esophageal squamous cell carcinoma by modulating SMAD1 expression

Esophageal squamous cell carcinoma （ESCC） is one of the most lethal cancers worldwide. In this study, we aimed to investigate the underlying mechanisms of metastasis inhibition by miR-205 in ESCC. In microRNA （miRNA） array and quantitative RT-PCR analyses, we found that the expression level of miR-205 was significantly lower in patients with lymph node metastasis compared with that in patients without lymph node metastasis. After transfection of miR-205 mimics or inhibitors into ESCC cell lines, a significant negative correlation was observed between the expression level of miR-205 and Smad 1. In luciferase reporter assays, we revealed that miR- 205 inhibited the expression of SMAD1 by targeting the 3＇ untranslated region （3＇-UTR） of SMAD1 mRNA in ESCC cells. Furthermore, our results showed that miR-205 sup- pressed the invasion and migration of ESCC cells, whereas Smadl increased their invasion and migration. Taken together, our study demonstrates that miR-205 functions as a suppressor of tumor metastasis by regulating SMAD1 expression through targeting the 3＇-UTR of SMAD1 mRNAin ESCC. Therefore, miR-205 may be a potential therapeutic target for miRNA-based therapy of ESCC.     

Z7 snoRNA：酿酒酵母中一种新的核仁小分子RNA

通过计算机分析国际分子生物学数据库和分子杂交等方法，在酿酒酵母中发现了一种新的核仁小分子ＲＮＡ：Ｚ７ ｓｎｏＲＮＡ。该ｓｎｏＲＮＡ具有ｂｏｘ Ｃ和ｂｏｘ Ｄ等结构元素，并有１４个核苷酸与１８Ｓ ｒＲＮＡ中的一段保守序列互补，属于典型的以核酸序列指导大分子ｒＲＮＡ甲基化的ｓｎｏＲＮＡ类型。Ｚ７ ｓｎｏＲＮＡ指导酿酒酵母１Ｓ ｒＲＮＡ中第５７８位的尿嘧啶核苷酸的核糖甲基化。Ｚ７ ｓｎｏＲＮＡ长８８个核     

多个发夹RNA的混合使用抑制O型和AsiaⅠ型口蹄疫病毒的复制

通过对国内流行的口蹄疫病毒(FMDV)毒株的序列分析,锁定RNA干扰的3个目标基因即3D,VP4和2B,分别编码聚合酶POL,病毒结构蛋白VP4和非结构蛋白2B,这3个靶基因序列在不同流行毒株之间相对保守.分别设计合成靶向这些基因序列的发夹RNA(short-hairpin RNA,shRNA)表达模板,构建了5个shRNA表达质粒p3D-NT56,p3D-NT19,pVP4-NT65,pVP4-NT19和2B-NT25.进行单独应用或混合应用,于细胞水平和乳鼠水平检测其抗病毒活性.结果显示,3D-NT56/19,VP4-NT65/19和2B-NT25shRNA对O型FMDV均有抑制作用,但是对AsiaⅠ型FMDV,仅2B-NT25shRNA具有较显著的抑制作用.3个shRNA表达质粒(p3D-NT56 pVP4-NT65 p2B-NT25,p3D-NT19 pVP4-NT19 p2B-NT25)的混合使用,不仅能够交叉抑制不同血清型FMDV的复制,而且这种抑制作用较单一shRNA延续更长的时间.     

人垂体嫌色性腺瘤细胞ConA受体和 RNA分布的研究

应用荧光标记的ConA和RNase结合半薄切片技术对人垂体嫌色性腺瘤细胞ConA受体和RNA的分布进行了观察。结果表明,ConA受体主要分布在腺瘤细胞的核膜上,细胞质和质膜上ConA受体较少。RNA在一些细胞中主要分布在核中,一些细胞的细胞质中也有RNA分布。总体而言RNA的合成水平较高。这些结果对于探讨垂体嫌色性腺瘤细胞的特性及病理发生具有一定的意义,同时可为临床诊断及临床检验提供一些依据。