相关实验视频

Updated: Jun 5, 2025

Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events

Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events

Published on: May 13, 2019

人类线粒体RNA聚合酶结构揭示了转录起点和滑动机制

Jiayu Shen^1,2, Quinten Goovaerts³, Yogeeshwar Ajjugal¹

¹Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA.

bioRxiv : the preprint server for biology

|December 16, 2024

概括

人类线粒体RNA聚合酶 (POLRMT) 和相关因子TFAM和TFB2M启动转录. 化EM结构揭示了POLRMT如何化DNA并选择起始位置,在-1位置发生滑动.

科学领域:

分子生物学分子生物学
结构生物学结构生物学
生物化学生物化学

背景情况:

人类线粒体转录受线粒体RNA聚合酶 (POLRMT) 和转录因子TFAM和TFB2M的调节.
从线粒体DNA促进体准确启动转录对于细胞能量生产至关重要.

研究的目的:

阐明人类POLRMT,TFAM和TFB2M的转录启动复合体形成和促进体化的结构机制.
了解线粒体转录过程中起点选择和RNA滑动的分子基础.

主要方法:

电子显微镜 (cryo-EM) 用于确定转录启动复合体的高分辨率结构.
促进者DNA,RNA转录和蛋白质-DNA相互作用的结构分析.

主要成果:

两种不同的启动复合体,IC3和滑动-IC3,得到了解决,显示了转录泡与RNA转录在+1和-1位置启动.
详细的相互作用揭示了促进体化的机制,涉及特定的基模板氨酸相互作用和非模板氨酸结合.
非模板链中的保存的AAA图案被TFB2M和POLRMT识别,稳定了启动复合体.
当二元RNA转移到-1位置时,观察到RNA滑动,这不是一个功能性起点.

结论:

这项研究为人类线粒体转录的启动提供了原子水平的见解.
确定了关键的蛋白质-DNA和蛋白质-RNA相互作用,控制促进体识别,化和开始部位选择.
证明RNA滑动是一个独特的事件,不代表另一个启动地点,为转录忠实性提供了新的理解.

关键词:

波罗的海波罗的海在TFAM中,我们可以使用TFAM.在TFB2M中,TFB2M是TFB2M.堕落的合成堕落的合成发起人融化融化活动转录启动转录启动

更多相关视频

High-throughput Purification of Affinity-tagged Recombinant Proteins

High-throughput Purification of Affinity-tagged Recombinant Proteins

Published on: August 26, 2012

Genome-wide Surveillance of Transcription Errors in Eukaryotic Organisms

Genome-wide Surveillance of Transcription Errors in Eukaryotic Organisms

Published on: September 13, 2018

相关概念视频

Bacterial Transcription

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 Initiation

Transcription Initiation

Initiation is the first step of transcription in eukaryotes. Prokaryotic RNA Polymerase (RNAP) can bind to the template DNA and start transcribing. On the other hand, transcription in eukaryotes requires additional proteins, called transcription factors, to first bind to the promoter region in the DNA template. This binding helps recruit the specific RNAP that can assemble on the DNA and start transcription.
The promoters and enhancers and their accessory proteins allow tight regulation of...

Eukaryotic RNA Polymerases

Eukaryotic RNA Polymerases

RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...

Chromatin Structure Regulates pre-mRNA Processing

Chromatin 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...

Transcription Elongation Factors

Transcription Elongation Factors

Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA...

Translesion DNA Polymerases

Translesion DNA Polymerases

Translesion (TLS) polymerases rescue stalled DNA polymerases at sites of damaged bases by replacing the replicative polymerase and installing a nucleotide across the damaged site. Doing so, TLS allows additional time for the cell to repair the damage before resuming regular DNA replication.
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...