时间无限的多分子ADP-ribosyl化限制了DNA复制压力,并促进了停滞的叉子保护
Julie Rageul1, Natalie Lo1, Amy L Phi1
1Department of Pharmacological Sciences, State University of New York at Stony Brook, Stony Brook, NY 11794, USA.
Cell reports
|February 23, 2024
概括
聚ADP-ribosyl化 (PARylation) 向无时间 (TIM) 降解,这对DNA复制叉稳定性至关重要. 抑制多基基聚合酶 (PARP) 干扰了这一过程,导致复制应激和分叉不稳定.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 聚ADP-ribosyl) 化 (PARylation) 是一个关键的翻译后修饰,调节DNA复制和修复.
- 聚 ((ADP-ribose) 聚合酶 (PARP) 1) 是主要催化PARylation的酶.
研究的目的:
- 为了研究PARylation在TIM (时间无限) 调节中的作用,一个复杂体支架.
- 阐明PARylation影响DNA复制叉稳定的机制.
主要方法:
- 生物化学测定检测TIM PARylation. 这是一个很好的方法.
- 使用PARylation-refractoryTIM突变体和PARP抑制剂进行细胞实验.
- 对DNA复制叉的动态和稳定性的分析.
主要成果:
- 时间无限 (TIM) 被确定为PARP1的基质,经历PARylation依赖的蛋白质体降解.
- PARP抑制或表达一种PARylation-refractory的TIM突变导致TIM在复制分叉中的积累,导致复制压力.
- 缺陷的 TIM 降解会损害 RAD51 的负载和反转叉的保护,增加 BRCA2 缺乏细胞的敏感性.
结论:
- PARylation通过调节 TIM 周转来控制复制体的改造,这对于停滞的叉子保护至关重要.
- PARP 抑制可以通过受损的 TIM 降解导致 DNA 复制分叉的不稳定.
相关概念视频
Restarting Stalled Replication Forks
5.8K
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,...
5.8K
The DNA Replication Fork
36.0K
An organism’s genome needs to be duplicated in an efficient and error-free manner for its growth and survival. The replication fork is a Y-shaped active region where two strands of DNA are separated and replicated continuously. The coupling of DNA unzipping and complementary strand synthesis is a characteristic feature of a replication fork. Organisms with small circular DNA, such as E. coli, often have a single origin of replication; therefore, they have only two replication...
36.0K
DNA Damage can Stall the Cell Cycle
9.2K
In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
9.2K
Translesion DNA Polymerases
10.0K
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...
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...
10.0K
Replication in Eukaryotes
13.8K
In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high fidelity before cell division, so there are many proteins that fulfill specialized roles in the replication process. Replication occurs in three phases: initiation, elongation, and termination, and ends with two complete sets of chromosomes in the nucleus.
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
13.8K
Negative Regulator Molecules
35.4K
Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
35.4K


