相关实验视频
Updated: Jun 3, 2026
11:53
Substrate Generation for Endonucleases of CRISPR/Cas Systems
Published on: September 8, 2012
通过转编码小RNA和宿主因子RNase III的CRISPRRNA成熟
Elitza Deltcheva1, Krzysztof Chylinski, Cynthia M Sharma
1The Laboratory for Molecular Infection Medicine Sweden, Umeå, Sweden.
Nature
|April 2, 2011
概括
科学家们发现了一种新的RNA分子,tracRNA,它可以帮助像Streptococcus pyogenes这样的细菌成熟CRISPRRNAs. 这种tracRNA与RNase III和Csn1一起,对细菌对侵袭菌体的免疫力至关重要.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细菌学 细菌学是一门学科.
背景情况:
- 克里斯普尔/卡斯系统为细菌和古生物提供了对外来遗传元素的适应性免疫力.
- 对于CRISPR/Cas功能来说,crRNA成熟是必不可少的,但负责的酶在所有亚型中并不普遍.
- 在许多细菌物种中,crRNA成熟的特定机制仍然不完全理解.
研究的目的:
- 研究人类病原体Streptococcus pyogenes中crRNA成熟的机制.
- 确定参与S. pyogenes中CRISPR/Cas介导免疫的新型成分.
- 阐明小RNAs在细菌适应性免疫中的作用.
主要方法:
- Streptococcus pyogenes 的差异性RNA测序.
- 小RNA分子的识别和表征.
- 生物化学测试用于确定crRNA成熟过程中已识别的RNA和蛋白质的功能.
- 菌挑战测试用于评估细菌免疫力.
主要成果:
- 在S. pyogenes中发现了tracrRNA,一个转编码的小RNA.
- 证明tracrRNA引导RNase III和Csn1进行crRNA成熟.
- 确定RNase III作为这种新型成熟途径必不可少的宿主因子.
- 确认tracrRNA,RNase III和Csn1是S. pyogenes对传播DNA的防御所需的.
结论:
- 在细菌适应性免疫中发现了小导向RNA成熟的新途径.
- 内源RNase III作为CRISPR/Cas介导RNA沉默中的宿主因子.
- 这一发现扩大了我们对CRISPR/Cas系统多样性和调节的理解.
- 已识别的途径对于保护Streptococcus pyogenes免受菌体感染至关重要.
相关概念视频
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...
02:53CRISPR and crRNAs
Bacteria and archaea are susceptible to viral infections just like eukaryotes; therefore, they have developed a unique adaptive immune system to protect themselves. Clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins (CRISPR-Cas) are present in more than 45% of known bacteria and 90% of known archaea.
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
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...
01:59CRISPR
Genome editing technologies allow scientists to modify an organism’s DNA via the addition, removal, or rearrangement of genetic material at specific genomic locations. These types of techniques could potentially be used to cure genetic disorders such as hemophilia and sickle cell anemia. One popular and widely used DNA-editing research tool that could lead to safe and effective cures for genetic disorders is the CRISPR-Cas9 system. CRISPR-Cas9 stands for Clustered Regularly Interspaced Short...
01:59CRISPR
Genome editing technologies allow scientists to modify an organism’s DNA via the addition, removal, or rearrangement of genetic material at specific genomic locations. These types of techniques could potentially be used to cure genetic disorders such as hemophilia and sickle cell anemia. One popular and widely used DNA-editing research tool that could lead to safe and effective cures for genetic disorders is the CRISPR-Cas9 system. CRISPR-Cas9 stands for Clustered Regularly Interspaced Short...
02:41Chromatin Structure Regulates pre-mRNA Processing
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...