核RNase III Drosha启动了微RNA处理的过程
Yoontae Lee1, Chiyoung Ahn, Jinju Han
1Institute of Molecular Biology and Genetics and School of Biological Sciences, Seoul National University, Seoul 151-742, Korea.
Nature
|September 26, 2003
概括
研究人员确定了人类的Drosha,一种RNase III酶,对于处理初级microRNAs (pri-miRNAs) 到核中的前体microRNAs (pre-miRNAs) 至关重要. 这一发现揭示了微RNA生物发生和基因调节的关键步骤.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 微RNA (miRNA) 是参与基因表达的小调节性RNA.
- 微RNA的生物发生路径,特别是初始处理步骤,尚未完全理解.
- 已知Dicer在细胞质中处理前体miRNAs (预miRNAs).
研究的目的:
- 为了确定负责核处理初级miRNA转录 (pri-miRNAs) 转化为前-miRNAs的酶.
- 为了阐明miRNA生物发生的初始步骤.
主要方法:
- 在体外切割试验中,使用免疫净化的人类Drosha.
- 在体内进行RNA干扰 (RNAi) 实验,以评估Drosha枯竭的影响.
- 对pri-miRNA,pre-miRNA和成熟miRNA水平的分析.
主要成果:
- 人类Drosha是一种RNase III酶,被确定为用于primi-miRNA处理的核心核酶.
- 德罗莎直接切割了pri-miRNA以在体外产生pre-miRNA.
- 在体内Drosha的耗尽导致了primiRNA的积累,并降低了primiRNA和成熟miRNA水平.
结论:
- 德罗莎对于核中的miRNA生物发生的启动步骤至关重要.
- 德罗沙和迪克可能在miRNAs的顺序处理中进行合作.
- 这些发现凸显了Drosha和Dicer在发展和分化过程中的miRNA介导基因调节中的作用.
相关概念视频
01:22MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
01:23RNA Interference
RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
01:23RNA Interference
RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
01:22MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
02:30siRNA - Small Interfering RNAs
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 ATP-dependent...
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 ATP-dependent...
01:22MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...