非模板的橄基化促进了RISC分裂的转录的降解
Fadia Ibrahim1, Jennifer Rohr, Won-Joong Jeong
1Biological Sciences and Plant Science Initiative, University of Nebraska, Lincoln, NE 68588, USA.
概括
研究人员发现了MUT68,该基因对于在小干扰RNA (siRNA) 沉默后降解RNA片段至关重要. 该基因编码了一种酶,该酶有助于分解目标转录,澄清了RNA干扰的关键步骤.
科学领域:
- 分子生物学分子生物学
- 在RNA生物学,RNA生物学.
- 基因规则 基因规则
背景情况:
- 双链RNA被Dicer加工成小干扰RNA (siRNA) 并集成到RNA诱导沉默复合体 (RISC) 中,可以调解真核生物中的基因沉默.
- RNA干扰 (RNAi) 是一种主要的基因沉默途径,主要以同源转录的降解为特征.
- 在siRNA介导的裂变后产生的RNA片段的命运在很大程度上是未知的.
研究的目的:
- 研究调控siRNA向转录的衰变的分子机制.
- 在RNA干扰中识别参与RNA碎片分离后处理的基因.
- 阐明特定酶在分裂RNA碎片的降解途径中的作用.
主要方法:
- 使用遗传选器在Chllamydomonas reinhardtii中进行基因鉴定.
- 分子克隆和鉴定基因的特征 (MUT68).
- 生物化学测试以确定MUT68蛋白的酶活性.
主要成果:
- 鉴定MUT68基因,这对于siRNA向转录的高效衰变至关重要.
- MUT68编码了一个非正规的多基酸聚合酶.
- MUT68酶在siRNA裂变后的5'RNA片段中添加未模拟的腺因,促进它们的外体依赖性降解.
结论:
- MUT68在RNA干扰途径中发挥着关键作用,通过促进分裂的RNA片段的降解.
- MUT68的多基化活性是针对这些碎片进行外体介导衰变的关键步骤.
- 这一发现为RNAi介导的基因沉默过程中RNA分子的完整生命周期提供了新的见解.
相关概念视频
Transcription
Overview
Transcription is the process of synthesizing RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. Additionally, many other proteins and regulatory sequences are involved in the proper synthesis of messenger RNA (mRNA). Regulation of transcription is responsible for the differentiation of all the different types of cells and often for the proper cellular response to environmental signals.
Transcription Can Produce Different Kinds...
Transcription is the process of synthesizing RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. Additionally, many other proteins and regulatory sequences are involved in the proper synthesis of messenger RNA (mRNA). Regulation of transcription is responsible for the differentiation of all the different types of cells and often for the proper cellular response to environmental signals.
Transcription Can Produce Different Kinds...
Riboswitches
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...
RACE - Rapid Amplification of cDNA Ends
Rapid Amplification of cDNA Ends, or RACE, is one of the most effective methods to obtain a full-length cDNA from an mRNA sequence between a known internal region to the unknown sequence at the 5’ or 3’ end. The unknown region is cloned in the cDNA by a gene-specific primer that binds the known end, and a hybrid primer that attaches a predefined anchor sequence to the unknown end of the cDNA. The sequence in between is amplified by PCR with an anchor primer and a gene-specific primer.
Since the...
Since the...
Bacterial Transcription
RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription
Transcription is the synthesis of RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. Additionally, many other proteins and regulatory sequences are involved in correctly synthesizing messenger RNA (mRNA). Transcriptional regulation is responsible for the differentiation of different types of cells and often for the proper cellular response to environmental signals.
Transcription Can Produce Different Kinds of RNA Molecules
In eukaryotes,...
Transcription Can Produce Different Kinds of RNA Molecules
In eukaryotes,...
Transcriptional Regulation: Riboswitches
Riboswitches are RNA elements that regulate gene expression by altering their secondary structures in response to specific effector molecules. These elements, located in the leader regions of certain mRNAs, act as transcriptional regulators by toggling between alternative conformations to control downstream gene expression. Riboswitch-mediated regulation is a precise mechanism for modulating biosynthetic pathways, as exemplified by the riboflavin biosynthesis pathway in Bacillus...


