共查询到20条相似文献,搜索用时 93 毫秒
1.
RNA干涉 (RNAi)是将双链RNA(dsRNA)导入细胞引起特异基因mRNA降解的一种细胞反应过程 .它是转录后基因沉默 (PTGS)的一种 .RNAi在生物界中广泛存在 .RNAi发生过程主要分为 3个阶段 :起始阶段 ,扩增阶段 ,效应阶段 .RNAi在维持基因组稳定、保护基因组免受外源核酸侵入、基因表达调控等方面发挥重要生物学作用 .RNAi作为基因沉默的一个工具 ,已被广泛用于基因功能研究、基因治疗和新药研究与开发等方面 . 相似文献
2.
RNAi在药物研究中的应用 总被引:2,自引:0,他引:2
RNA干扰是双链RNA分子在mRNA水平上诱发的序列特异性的转录后基因表达沉默。在哺乳动物细胞里,RNAi可以由21-25个核苷酸长度的小干扰RNA(siRNA)触发,在后基因组时代的基因功能研究和药物开发中具有广阔的应用前景。现针对近年RNAi在药物研究中的应用包括应用RNAi发现新药靶、辅助确认药靶、RNAi药物、RNAi与耐药性等方面作一综述。 相似文献
3.
4.
RNA干扰(RNA interference,RNAi)是一种由双链RNA诱发的转录后水平的基因沉默现象,是近几年发展起来的基因表达调节新机制。RNAi广泛存在于真菌、植物和动物中,这种调控可以由siRNA、shRNA及miRNA等小分子RNA参与。在此主要对RNAi的研究进展如背景、分子调控机制、存在的问题和应用前景等进行了综述。 相似文献
5.
RNA干扰(RNAi)是由小干扰RNA(siRNA)引发的生物细胞内同源基因的转录后基因沉默(PTGS)现象,是一种古老的生物抵抗外在感染的防御机制。RNAi因其在维持基因组稳定、调控基因表达和保护基因组免受外源核酸侵入等方面发挥的重要作用,已被广泛用于探索基因功能、基因治疗和新药的研发。外源导入siRNA引发的RNAi可以特异性抑制病毒的复制与感染,为抗病毒感染治疗开辟了一条新的途径。 相似文献
6.
7.
RNA干扰(RNA interference,RNAi)是指双链RNA诱导同源mRNA降解从而导致基因表达抑制的现象,其效应分子是一种短片段双链RNA分子,被称为小分子干扰RNA。RNAi技术作为新兴的基因表达抑制方法,在功能基因组学、基因表达调控、基因治疗等领域得到了广泛应用。并将极大促进当前生物科学研究的发展。 相似文献
8.
9.
10.
RNA干扰技术在哺乳动物中的应用 总被引:12,自引:0,他引:12
RNA干扰(RNAi)是生物界普遍存在的一种抵御外来基因和病毒感染的进化保守机制.RNAi是由双链RNA触发的转录后基因沉默机制,具有序列特异性,在哺乳动物细胞中,RNAi由21~23个核苷酸组成的双链RNA引发.小干扰RNA(siRNA)可以在体外合成或通过表达载体在哺乳动物细胞内合成.由于RNAi技术具有快速、简单和特异性强等特点,在基因功能研究、抗病毒治疗和抗肿瘤治疗等方面有广泛的应用前景. 相似文献
11.
Jake Baum Anthony T. Papenfuss Gunnar R. Mair Chris J. Janse Dina Vlachou Andrew P. Waters Alan F. Cowman Brendan S. Crabb Tania F. de Koning-Ward 《Nucleic acids research》2009,37(11):3788-3798
Techniques for targeted genetic disruption in Plasmodium, the causative agent of malaria, are currently intractable for those genes that are essential for blood stage development. The ability to use RNA interference (RNAi) to silence gene expression would provide a powerful means to gain valuable insight into the pathogenic blood stages but its functionality in Plasmodium remains controversial. Here we have used various RNA-based gene silencing approaches to test the utility of RNAi in malaria parasites and have undertaken an extensive comparative genomics search using profile hidden Markov models to clarify whether RNAi machinery exists in malaria. These investigative approaches revealed that Plasmodium lacks the enzymology required for RNAi-based ablation of gene expression and indeed no experimental evidence for RNAi was observed. In its absence, the most likely explanations for previously reported RNAi-mediated knockdown are either the general toxicity of introduced RNA (with global down-regulation of gene expression) or a specific antisense effect mechanistically distinct from RNAi, which will need systematic analysis if it is to be of use as a molecular genetic tool for malaria parasites. 相似文献
12.
A heat shock inducible and inheritable RNA interference (RNAi) system was developed in the silkworm (Bombyx mori). RNAi transgenic silkworms were generated by injecting silkworm eggs with a piggyBac transposon plasmid carrying RNAi sequence against target gene driven by the Drosophila heat shock protein 70 (HSP70) promoter and the helper plasmid expressing piggyBac transposase. The transgenic EGFP gene and the endogenous eclosion hormone (EH) gene were chosen respectively as the target genes. In the RNAi transgenic silkworms, heat shock at 42 degrees C significantly and specifically reduced the expression of EGFP or EH gene in silkworms according to the corresponding RNAi targeting sequence but not in silkworms with the irrelevant RNAi sequence demonstrating the efficiency and specificity of the RNAi effect. Heat shock in the pupal stage hampered pupal-adult eclosion and reduced egg fertility in EH RNAi transgenic silkworms but not in the wild type or EGFP RNAi transgenic silkworms. The establishment of this heat inducible and inheritable conditional RNA interference system in silkworms provided an approach for the first time to dissect the functions of target genes in silkworms at different stages. 相似文献
13.
RNA interference in mammalian cells by chemically-modified RNA 总被引:24,自引:0,他引:24
RNA interference (RNAi) is proving to be a robust and versatile technique for controlling gene expression in mammalian cells. To fully realize its potential in vivo, however, it may be necessary to introduce chemical modifications to optimize potency, stability, and pharmacokinetic properties. Here, we test the effects of chemical modifications on RNA stability and inhibition of gene expression. We find that RNA duplexes containing either phosphodiester or varying numbers of phosphorothioate linkages are remarkably stable during prolonged incubations in serum. Treatment of cells with RNA duplexes containing phosphorothioate linkages leads to selective inhibition of gene expression. RNAi also tolerates the introduction of 2'-deoxy-2'-fluorouridine or locked nucleic acid (LNA) nucleotides. Introduction of LNA nucleotides also substantially increases the thermal stability of modified RNA duplexes without compromising the efficiency of RNAi. These results suggest that inhibition of gene expression by RNAi is compatible with a broad spectrum of chemical modifications to the duplex, affording a wide range of useful options for probing the mechanism of RNAi and for improving RNA interference in vivo. 相似文献
14.
HIV-1 TAR element is processed by Dicer to yield a viral micro-RNA involved in chromatin remodeling of the viral LTR 总被引:1,自引:0,他引:1
Zachary Klase Prachee Kale Rafael Winograd Madhur V Gupta Mohammad Heydarian Reem Berro Timothy McCaffrey Fatah Kashanchi 《BMC molecular biology》2007,8(1):63
Background
RNA interference (RNAi) is a regulatory mechanism conserved in higher eukaryotes. The RNAi pathway generates small interfering RNA (siRNA) or micro RNA (miRNA) from either long double stranded stretches of RNA or RNA hairpins, respectively. The siRNA or miRNA then guides an effector complex to a homologous sequence of mRNA and regulates suppression of gene expression through one of several mechanisms. The suppression of gene expression through these mechanisms serves to regulate endogenous gene expression and protect the cell from foreign nucleic acids. There is growing evidence that many viruses have developed in the context of RNAi and express either a suppressor of RNAi or their own viral miRNA. 相似文献15.
两种高效 RNA 干涉载体系统的构建及应用 总被引:1,自引:0,他引:1
在真核细胞基因功能研究中, RNA 干涉 (RNAi) 已成为一种强有力的选择性沉默基因表达的实验工具. 建立一套可在哺乳动物培养细胞中高效、经济地表达 siRNA 的载体系统是 RNA 干涉研究的必要前提之一. 从 HepG2 细胞基因组 DNA 中克隆得到 H1 全长启动子 (374 bp),以之为基础构建了两套 RNA 干涉载体系统, pSL 和带有绿色荧光蛋白 (EGFP) 标签的 pESL ,并对 p53 基因进行了相应的 RNA 干涉研究. 干涉质粒瞬时转染 HepG2 细胞后,分别利用半定量 RT-PCR 和蛋白质印迹检测 p53 表达水平. 与商品化载体 pSilencerTM 3.1-H1 hygro 相比, pSL 和 pESL 对 p53 基因表达具有更高的干涉效率. 结果显示:干涉载体 pSL 和 pESL 能高效特异地下调目的基因表达,可作为哺乳动物中基因功能分析的有效工具. 相似文献
16.
RNA干扰(RNA interference,RNAi)是指在生物体细胞内,外源性或内源性的双链RNA(double-stranded RNA,dsRNA)引起与其同源mRNA特异性的降解,因而抑制其相应的基因表达过程.由于它能够高度特异性、高效性地抑制基因的表达,因此在研究基因功能及表达调控、信号传导通路、药物靶点的鉴定和基因药物开发等方面具有良好的应用前景.主要介绍RNAi可能的分子机制、分子生物学特性、产生方法及其在肿瘤研究中的应用. 相似文献
17.
Short hairpin RNA and retroviral vector-mediated silencing of p53 in mammalian cells 总被引:6,自引:0,他引:6
Liu XD Ma SM Liu Y Liu SZ Sehon A 《Biochemical and biophysical research communications》2004,324(4):1173-1178
18.
19.
20.
RNA干扰是指dsRNA抑制细胞内同源基因表达的现象,RNA干扰现象自发现以来在短短的几年里,已成功地用于不同种属的生物研究。dsRNA不仅参与内源基因表达调控,而且能够抑制宿主内病原微生物基因的表达,参与构筑生物体的防御机制。近年来,运用RNAi技术在哺乳动物中的研究不断深入,尤其是抑制病毒复制的研究成果令人欣喜,这为人类动物抗病毒治疗提供了新的思路。 相似文献