通过RNA介导的RNA降解和甲基甲酸盐合成酶A在花中沉默
M Metzlaff1, M O'Dell, P D Cluster
1John Innes Centre, Norwich Research Park, Colney, United Kingdom.
Cell
|March 21, 1997
概括
转录后RNA降解导致转基因花中合酶 (CHS) 基因沉默,导致白色的花朵. 这涉及RNA配对和分裂,影响内源性和转基因CHSRNA.
科学领域:
- 植物分子生物学 植物分子生物学
- 基因规则 基因规则
- 在RNA生物学,RNA生物学.
背景情况:
- 基合成酶 (CHS) 对于植物中黄色素生物合成至关重要.
- 转录后基因沉默 (PTGS) 可以通过RNA降解途径发生.
- 表达chsA基因的转基因花有时会表现出CHS活性和色素的丧失.
研究的目的:
- 为了研究转基因Petunia中转录后chsARNA降解的机制.
- 为了确定参与CHS基因沉默的RNA区域和结构.
- 阐明影响CHS表达的PTGS的分子基础.
主要方法:
- 对多基化 (多基A) +) 和非多基化 (多基A) - - chsA RNA 的分析.
- 使用3'末端特定RNA片段进行RNA降解试验.
- 序列分析以确定chsARNA中互补的区域.
主要成果:
- 转基因小花显示出由于chsARNA降解而减少的CHS活性和紫色素.
- 在沉默植物中检测到较短的多A) +和多A) - chsARNA.
- 内源性chsA的3'端特异性RNA片段对降解具有抗性,映射到一个互补区域.
结论:
- 一个涉及RNA-RNA配对和内核分裂的模型解释了CHSRNA降解.
- 这种机制有助于Petunia中 chalcone合成酶基因的PTGS.
- 了解这些RNA降解途径是控制植物基因表达的关键.
相关概念视频
Chromatin Structure Regulates pre-mRNA Processing
6.6K
In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
The chromatin structure, especially...
6.6K
Nonsense-mediated mRNA Decay
9.4K
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
9.4K
Riboswitches
8.0K
Riboswitches are non-coding mRNA domains that regulate the transcription and translation of downstream genes without the help of proteins. Riboswitches bind directly to a metabolite and can form unique stem-loop or hairpin structures in response to the amount of the metabolite present. They have two distinct regions – a metabolite-binding aptamer and an expression platform.
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
8.0K
mRNA Stability and Gene Expression
5.0K
The structure and stability of mRNA molecules regulates gene expression, as mRNAs are a key step in the pathway from gene to protein. In eukaryotes, the half-life of mRNA varies from a few minutes up to several days. mRNA stability is essential in growth and development. The absence of the proteins regulating its stability, such as tristetraprolin in mice, can cause systemic issues, including bone marrow overgrowth, inflammation, and autoimmunity.
Cis-acting Elements involved in mRNA stability
Cis-acting Elements involved in mRNA stability
5.0K
siRNA - Small Interfering RNAs
13.4K
Small interfering RNAs, or siRNAs, are short regulatory RNA molecules that can silence genes post-transcriptionally, as well as the transcriptional level in some cases. siRNAs are important for protecting cells against viral infections and silencing transposable genetic elements.
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the...
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the...
13.4K
Experimental RNAi
6.5K
RNA interference (RNAi) is a cellular mechanism that inhibits gene expression by suppressing its transcription or activating the RNA degradation process. The mechanism was discovered by Andrew Fire and Craig Mello in 1998 in plants. Today, it is observed in almost all eukaryotes, including protozoa, flies, nematodes, insects, parasites, and mammals. This precise cellular mechanism of gene silencing has been developed into a technique that provides an efficient way to identify and determine the...
6.5K


