拓酶I是一种进化保守的卫星DNA转录的关键调节器
Zhen Teng1, Lu Yang1, Qian Zhang1
1Department of Biochemistry & Molecular Biology, Tulane University School of Medicine, 1430 Tulane Ave, New Orleans, LA, 70112, USA.
Nature communications
|June 17, 2024
概括
拓酶I (TopI) 促进了α卫星DNA的转录,这对染色体分离至关重要. 这种机制在各个物种中都存在,并通过DNA双链断裂来激活.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 细胞生物学 细胞生物学
背景情况:
- 卫星DNA转录对于染色体分离至关重要.
- 卫星DNA转录的调节仍然不太了解.
研究的目的:
- 研究拓糖酶I (TopI) 和拓糖酶II (TopII) 在卫星DNA转录中的作用.
- 阐明TopI在调节α-卫星DNA转录中的机制.
- 确定DNA双链断裂 (DSB) 对卫星转录的影响.
主要方法:
- 在中心分子上对TopI的定位研究.
- 对TopI与RNA聚合酶II (RNAPII) 的相互作用进行分析.
- 对响应DSBs的卫星转录的评估.
- 在不同细胞类型和生物体 (人,小鼠,多索菲拉) 中进行比较分析.
主要成果:
- 拓酶I (TopI),而不是TopII,促进了α-卫星DNA转录.
- TopI局限于中间体,结合RNAP II,并增强RNAP II的延长.
- DNA双链断裂 (DSB) 显著刺激了以TopI依赖的方式的α-卫星转录.
- DSB诱导的RNAs形成了核斑点.
- 依赖于TopI的卫星转录在小鼠和虫细胞和组织中得到保存.
结论:
- 拓酶I是α-卫星DNA转录的关键调节者.
- 一个涉及TopI的保存机制调节了跨物种的卫星转录.
- 卫星转录在响应DNA损伤时被动态调节.
相关概念视频
DNA Topoisomerases
31.2K
Topoisomerases are enzymes that relax overwound DNA molecules during various cell processes, including DNA replication and transcription. These enzymes regulate positive and negative DNA supercoiling without changing the nucleotide sequence. DNA overwinding in a clockwise direction results in positively supercoiled DNA, whereas underwinding in a counterclockwise direction produces negatively supercoiled DNA.
Types and Mechanism of action
Topoisomerases are divided into two main types. ...
Types and Mechanism of action
Topoisomerases are divided into two main types. ...
31.2K
Telomeres and Telomerase
23.3K
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...
23.3K
Conservative Site-specific Recombination and Phase Variation
6.0K
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
6.0K
Replication in Eukaryotes
170.6K
Overview
170.6K
RNA Polymerase II Accessory Proteins
9.2K
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
9.2K
DNA Helicases
21.3K
DNA unwinding helicase enzymes are a type of motor protein. Motor proteins can translocate along filaments or polymers using energy generated from ATP hydrolysis. Helicases are involved in all the important cellular processes where DNA unwinding is required, such as DNA replication, repair, recombination, and transcription. They are present in all living organisms, but vary in their structure, function, and mechanism of action. For example, in prokaryotes, DnaB helicase binds and translocates...
21.3K


