相关实验视频
Updated: Jul 20, 2026

06:59
Nanomanipulation of Single RNA Molecules by Optical Tweezers
Published on: August 20, 2014
概括
这项研究揭示了对S-adenosylmethionine (SAM) 响应的 рибо开关的3D结构. 这一发现增强了对细菌中RNA分子对基因调节的理解.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 遗传学 是一个遗传学.
背景情况:
- рибо开关是RNA调节元件,通过代谢物结合控制基因表达.
- 它们由体和表达平台领域组成,对于感知细胞内代谢物水平至关重要.
- 在格拉姆阳性细菌中, рибо开关调节了超过2%的基因,对各种小分子作出反应.
研究的目的:
- 为了确定一个特定的S-adenosylmethionine (SAM) 响应的核开关的高分辨率晶体结构.
- 阐明SAM识别和下游基因调节的分子机制.
主要方法:
- 采用X射线晶体学,获得了2.9安格斯特罗姆的分辨率结构.
- 这项研究涉及将 рибо开关与其连接体S-adenosylmethionine复杂化.
主要成果:
- 晶体结构揭示了SAM-riboswitch复合体的复杂3D架构.
- RNA通过直接和间接的读取机制来识别SAM,几乎涉及所有功能组.
- 干结合触发了三级相互作用,将体和表达平台连接起来.
结论:
- 确定的结构为SAM-riboswitch功能提供了原子层面的洞察力.
- 这种连接体识别和信号传导的机制对于细菌的基因表达控制至关重要.
- 这些发现有助于理解基于RNA的调节和潜在的治疗点.
相关概念视频
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...
Regulated mRNA Transport
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...
Regulated mRNA Transport
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...
Nucleic Acid Structure
The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group on the ribose's second carbon and a hydrogen on the deoxyribose's second carbon. The phosphate residue attaches to the hydroxyl group of the 5′ carbon of one sugar and the hydroxyl group of the 3′ carbon of the sugar of the next nucleotide, which forms a 5′ to 3′ phosphodiester linkage.
DNA Structure
DNA has a double-helix structure. The...
DNA Structure
DNA has a double-helix structure. The...
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...
Translational Regulation
Translational regulation in prokaryotes ensures efficient protein synthesis by controlling ribosome access to mRNA. This regulation is mediated by secondary RNA structures, including translational riboswitches, RNA thermometers, and small RNAs (sRNAs), which respond to intracellular and environmental signals to modulate gene expression.Translational RiboswitchesRiboswitches in the leader region of mRNAs can regulate translation by altering the accessibility of the Shine-Dalgarno (SD) sequence,...

