概括
表皮生长因子受体 (EGFR) 与细胞增殖有关. 研究表明EGFR相关的DNA切割活性,但这项研究表明它源于一个单独的分子实体,而不是EGFR本身.
科学领域:
- 分子生物学分子生物学
- 细胞信号传递 细胞信号传递
- 生物化学 生物化学
背景情况:
- 皮表皮生长因子受体 (EGFR) 是一种对调节细胞增殖至关重要的跨膜蛋白.
- EGFR信号传递涉及一个面向外部的EGF结合域和一个内部的氨酸激酶域.
- 从等离子体膜到核的信号传输的精确机制仍然不清楚.
研究的目的:
- 研究与表皮生长因子受体 (EGFR) 相关的DNA-nicking活动.
- 要确定DNA-nicking活动是EGFR的内在功能还是与其他分子相关的.
主要方法:
- 用糖分梯度离心法来描述DNA断活动.
- 此前曾有报道称,纯化的人类和小鼠EGF受体表现出ATP依赖的DNA-nicking.
主要成果:
- 该研究分析了与表皮生长因子受体 (EGFR) 相关的DNA-nicking活动.
- 结果表明,DNA-nicking活动不是EGFR的内在属性.
- 发现该活性与EGFR分离的独特分子物种有关.
结论:
- 与EGFR相关观察到的DNA-nicking活动并不固有于受体本身.
- 一个单独的分子实体负责DNA切割功能.
- 这一发现澄清了涉及DNA拓的EGFR介导细胞反应的分子基础.
相关概念视频
01:08Nucleotide Excision Repair
Overview
01:54Base Excision Repair
One of the common DNA damages is the chemical alteration of single bases by alkylation, oxidation, or deamination. The altered bases cause mispairing and strand breakage during replication. This type of damage causes minimal change to the DNA double helix structure and can be repaired by the base excision repair (BER) pathways. BER corrects damaged DNA sequences by removing the damaged base and restoring the original base sequence using the complementary strand as a template.
The first step of...
The first step of...
01:02Long-patch Base Excision Repair
Since the discovery of the two BER pathways, there has been a debate about how a cell chooses one pathway over the other and the factors determining this selection. Numerous in vitro experiments have pointed out multiple determinants for the sub-pathway selection. These are:
02:31Homologous Recombination
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
01:38Nucleotide Excision Repair
DNA Distortion and Damage
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
01:20Mismatch Repair
Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...