RAS基因在K562细胞凋亡中的作用研究

发布时间：2018-05-27 18:12

本文选题：N-RAS基因 + 二级结构　；参考：《第一军医大学》2005年硕士论文

【摘要】：RAS基因是最容易被激活的人类原癌基因之一,在一个庞大的信号传递网络中起着着分子开关的作用,这个网络主要控制细胞的增殖和分化。RAS基因突变后被激活,成为具有致癌作用的癌基因,编码具有持续活性的蛋白,持续激活下游通路,可使细胞发生不依赖于生长因子的生存和增殖,导致肿瘤的形成。就目前所知,点突变是RAS基因激活的主要方式。在已发现多种不同的肿瘤(大部分为上皮细胞衍生而来)中,物理或化学致癌因素均可引起RAS基因突变。由于其在肿瘤发生发展中的重要作用,RAS基因已成为基础及临床研究的重要对象。K-RAS突变常见于胰、结肠及肺部腺癌,泌尿系统肿瘤则以H-RAS突变为主,而在急性淋巴细胞白血病,慢性淋巴细胞白血病等血液系统肿瘤中以N-RAS突变为主。研究RAS的信号转导通路有助于寻找新的抗癌药物治疗作用靶点。但是,越来越多的证据显示,信号转导通路中,各信号通路是个复杂的网络结构,各通路是互相影响、互相交叉的。由于这种复杂的网络结构的存在,对RAS基因在各个控制细胞表型的信号通路中的位置与作用的研究存在着一定的困难。 RNA干扰(RNA interference,RNAi)是近几年内迅速发展起来的基因沉默方法,用于特异性去除或降低某个或某些基因在细胞或机体中的表达,研究正常基因的结构、功能、信号传导通路机制。研究发现,体外合成的21～23nt的siRNA
[Abstract]:The RAS gene is one of the most easily activated human proto-oncogenes, acting as a molecular switch in a large signaling network that controls cell proliferation and differentiation. Ras gene mutations are then activated. As a carcinogenic oncogene, which encodes a protein with sustained activity and continuously activates downstream pathways, cell survival and proliferation are independent of growth factors, leading to tumor formation. As far as known, point mutation is the main mode of RAS gene activation. In many different tumors, most of which are derived from epithelial cells, both physical and chemical carcinogenic factors can cause mutations in the RAS gene. Because of its important role in tumorigenesis and development, Ras gene has become an important object of basic and clinical research. K-RAS mutation is common in pancreatic, colon and lung adenocarcinoma, and urinary system tumors are mainly H-RAS mutation, but in acute lymphoblastic leukemia. N-RAS mutation was dominant in hematological tumors such as chronic lymphoblastic leukemia. To study the signal transduction pathway of RAS is helpful to find new targets of anticancer drug therapy. However, more and more evidence shows that, in signal transduction pathways, each signal pathway is a complex network structure, and each pathway interacts with each other. Due to the existence of this complex network structure, it is difficult to study the position and role of RAS gene in various signal pathways that control cell phenotype. RNA interference RNAi is a rapidly developed gene silencing method in recent years. It is used to specifically remove or decrease the expression of one or some genes in cells or organisms, and to study the structure, function and signal transduction pathway mechanism of normal genes. It was found that siRNA of 21~23nt was synthesized in vitro.
【学位授予单位】：第一军医大学
【学位级别】：硕士
【学位授予年份】：2005
【分类号】：R346

【引证文献】