相关实验视频
Updated: May 31, 2026

06:59
Nanomanipulation of Single RNA Molecules by Optical Tweezers
Published on: August 20, 2014
拥挤促进了人体端粒酶RNA中从针头转变为伪结的变化
Natalia A Denesyuk1, D Thirumalai
1Department of Chemistry and Biochemistry and Biophysics Program, Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA.
Journal of the American Chemical Society
|July 9, 2011
概括
细胞拥挤增强了人体端粒酶中伪结 (PK) 结构的稳定性,这对其功能至关重要. 这种拥挤效应可能有助于恢复某些遗传突变中的端粒酶活性.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 计算生物学 计算生物学
背景情况:
- 人类端粒酶RNA核心域中的伪节点 (PK) 结构对于其生物功能至关重要.
- 这种PK结构存在于平衡状态,具有延伸的头 (HP) 形状.
- 了解影响PK稳定性的因素对于端粒酶功能和相关疾病,如先天性皮质障碍症至关重要.
研究的目的:
- 为了研究分子拥挤对伪结 (PK) 与人体端粒酶中延伸毛针 (HP) 结构稳定性的影响.
- 为了探索不同的群众尺寸和组成如何影响这些RNA结构的相对稳定性.
- 预测分子拥挤的潜力,以拯救基因组稳定性受损的突变体中的端粒酶活性.
主要方法:
- 利用分子模拟,使用人类端粒酶RNA核心域的粗粒度模型.
- 根据PK和HP结构的实验化配置文件验证了模型.
- 模拟了各种拥挤条件,包括单分散和混合尺寸颗粒悬浮,模拟了像大肠杆菌这样的细胞环境.
主要成果:
- 分子拥挤显著提高了PK结构相对于HP结构的稳定性,无论是野生类型的还是先天性肌肉异常突变的.
- 拥挤对稳定的影响取决于拥挤的大小;较小的拥挤在稳定紧结构方面更有效.
- 在复杂的混合物中,最小的crowder主导着稳定效应,当crowder大小小小于展开的RNA时,观察到添加效应.
结论:
- 分子拥挤在稳定人类端粒酶的功能性伪结结构方面发挥着至关重要的作用.
- 拥挤条件,特别是较小分子的存在,可以调节PK和HP结构之间的平衡.
- 据预测,分子拥挤可能会在表现PK稳定性降低的突变分子中恢复端粒酶活性.
相关概念视频
Telomeres and Telomerase
In eukaryotic DNA replication, a single-stranded DNA fragment remains at the end of a chromosome after the removal of the final primer. This section of DNA cannot be replicated in the same manner as the rest of the strand because there is no 3’ end to which the newly synthesized DNA can attach. This non-replicated fragment results in gradual loss of the chromosomal DNA during each cell duplication. Additionally, it can induce a DNA damage response by enzymes that recognize single-stranded DNA.
Telomeres and Telomerase
In eukaryotic DNA replication, a single-stranded DNA fragment remains at the end of a chromosome after the removal of the final primer. This section of DNA cannot be replicated in the same manner as the rest of the strand because there is no 3’ end to which the newly synthesized DNA can attach. This non-replicated fragment results in gradual loss of the chromosomal DNA during each cell duplication. Additionally, it can induce a DNA damage response by enzymes that recognize single-stranded DNA.
Transcription Attenuation in Prokaryotes
Transcriptional attenuation occurs when RNA transcription is prematurely terminated due to the formation of a terminator mRNA hairpin structure. Bacteria use these hairpins to regulate the transcription process and control the synthesis of several amino acids including histidine, lysine, threonine, and phenylalanine. Transcription attenuation takes place in the non-coding regions of mRNA.
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
Restarting Stalled Replication Forks
DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...
RNA Structure
The basic structure of RNA consists of a string of ribonucleotides attached by phosphodiester bonds. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA) involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three...
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA) involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three...
RNA Structure
Overview
The basic structure of RNA consists of a five-carbon sugar and one of four nitrogenous bases. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA): messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three RNA types consist of a...
The basic structure of RNA consists of a five-carbon sugar and one of four nitrogenous bases. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA): messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three RNA types consist of a...