RNA干扰及其机制(精)

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2006年的诺贝尔生理学奖获得者：
Andrew Z. Fire Craig C. Mello
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Fig 2. Analysis of RNA-interference effects in individual cells. Fluorescence micrographs show
progeny of injected animals from GFP-reporter strain PD4251 (a C. elegans strain expressing GFP fluorescence protein) (使用外源导入的报告基因). Control dsRNA ds-gfp RNA
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The heart of the RNAi mechanism
1. Dicer: an RNaseIII-like multidomain ribonuclease that first processes input dsRNA into small fragments called short interfering RNAs (siRNAs) or microRNAs (miRNA). Dicer then helps load its small RNA products into RISC. 2. RISC (RNA induced silencing complexes) (RNA诱导的沉默复合体): a large multiprotein complex that direct the bound siRNA or miRNA to its target and inhibit the target gene expression.
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2. Short interfering RNA (siRNAs) are produced from dsRNA and direct machinery that switch off genes in various way. [Mechanism-机制] 从双链RNA产生的小干扰RNA可以指 导用不同机制关闭基因的细胞机器
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The targets of the RNAi-directed gene silencing 1.Degradation of the target mRNA (引 起靶标mRNA的降解), 2.Inhibition of translation of the target mRNA (抑制靶标mRNA的翻译), 3.Silencing the gene transcription from the target promoter (引起靶标启 动子的转录沉默).
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•Molecular Biology Course
Chapter 8: RNA in regulation The mechanism of RNAi and the role of miRNA in development and cancer
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CHAPTER 18 RNAi and miRNA in development and cancergenesis
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The question to be addressed is “Why exogenous dsRNA can inhibit expression of genes homologous to that RNA?”
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Exogenous dsRNA 外源双链RNA
Figure 17-30 RNAi silencing
hybridization in embryos) (胚胎的原位杂交).
No hybridization and staining + hybridization (endogenous mex-3 RNA)
+antisense +hybridization
+ds mex-3 RNA +hybridization
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An plant immune system: Virus-induced gene silencing (植物病毒引起的基因沉默). Most plant viruses have single-stranded RNA genomes, which are released from the protein coat of their virus particles as they enter a cell.Their genomic RNA is then replicated by the virus encoded RNAdependent RNA polymerase to produce sense and antisense RNA, which can hybridize to form dsRNA and trigger an RNAi response against their own sequences.
一、RNA干扰及其机制
Topic 1: RNA interference and its mechanism
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1 Double-stranded RNA inhibits expression of genes homologous to that RNA. [phenomena-现象]
双链RNA抑制含其同源序列基因的表达
Welcome Each of You to My Molecular Biology Class
Molecular Biology of the Gene, 5/E --- Watson et al. (2004)
Part I: Chemistry and Genetics
Part II: Maintenance of the Genome
Part III: Expression of the Genome
Part IV: Regulation Part V: Methods
2005-5-10
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Chapter 16 Regulation principles and How genes are regulated in bacteria Chapter 17 Basic mechanism of gene expression in eukaryotes Chapter 18 The mechanism of RNAi and the role of miRNA in development and cancer
Young larva (幼虫)
Adultห้องสมุดไป่ตู้(成虫)
adult body wall at high magnification (高放大倍数的 成虫体壁)
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Fig 3. Effects of mex-3 RNA interference on levels of the endogenous mRNA (in situ