相关实验视频
Updated: Jan 29, 2026
10:00
Assaying DNA Damage in Hippocampal Neurons Using the Comet Assay
Published on: December 19, 2012
28.1K
开发一种使用稳定的人类肝细胞的DNA损伤测定系统
Masayuki Mishima1, Kazuki Izawa2, Masataka Tsuda2
1Division of Genome Safety Science, National Institute of Health Sciences (NIHS), 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-9501, Japan. mishimamsy@nihs.go.jp.
概括
使用稳定的人类肝细胞的新分析检测到DNA损伤,克服了毒理学上的物种差异. 这种方法为基因毒性测试提供了可靠的工具,更好地反映了人类的新陈代谢.
科学领域:
- 毒理学 毒理学 毒理学
- 遗传学 遗传学 是一个
- 生物化学 生物化学
背景情况:
- 各种物种的新陈代谢差异对毒理学研究构成挑战.
- 人类的新陈代谢系统是高度可变的,限制了标准化的体外基因毒性测试.
- 需要基因毒性测试,以更好地模仿人类生理学.
研究的目的:
- 开发和验证一个细胞内ELISA系统,用于测量稳定的人类肝细胞中的DNA损伤.
- 为了评估人类肝细胞中γH2AX标记物的实用性,用于基因毒性评估.
- 建立最佳的测试条件,以检测人类相关系统中的基因毒性反应.
主要方法:
- 在稳定的人类肝细胞 (HepaSH细胞) 中测量γH2AX (DNA损伤标志物) 的细胞内ELISA的开发.
- 肝炎SH细胞稳定地表达代谢酶和药物载体,模仿人类生理学.
- 对已知的间接变异原体 (例如,烯) 暴露HepaSH细胞以评估剂量依赖的DNA损伤.
主要成果:
- 开发的 γH2AX-SHE 试验成功检测了间接变异原体对DNA损伤的剂量依赖性增加.
- 需要16小时或更长的治疗时间才能检测出基因毒性反应.
- 高细胞毒性 (48小时暴露) 可能会干扰精确的γH2AX量化.
结论:
- γH2AX-SHE测定是一种有价值的工具,用于检测人类相关的代谢环境中的DNA损伤.
- 建议的测定条件包括24小时的治疗期和DMSO度≤1%.
- 高度细胞毒性剂量 (<60%细胞存活率) 的反应需要仔细解释,因为可能缺乏生物相关性.
相关概念视频
02:36DNA Damage Can Stall the Cell Cycle
3.1K
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...
3.1K
02:36DNA Damage can Stall the Cell Cycle
10.1K
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...
10.1K
02:25Overview of DNA Repair
33.6K
In order to be passed through generations, genomic DNA must be undamaged and error-free. However, every day, DNA in a cell undergoes several thousand to a million damaging events by natural causes and external factors. Ionizing radiation such as UV rays, free radicals produced during cellular respiration, and hydrolytic damage from metabolic reactions can alter the structure of DNA. Damages caused include single-base alteration, base dimerization, chain breaks, and cross-linkage.
Chemically...
Chemically...
33.6K
02:57DNA-only Transposons
17.4K
DNA-only transposons are called autonomous transposons since they code for the enzyme transposase that is required for the transposition mechanism. Insertion of transposons can alter gene functions in multiple ways. They can mutate the gene, alter gene expression by introducing a novel promoter or insulator sequence, introduce new splice sites, and change the mRNA transcripts produced, or remodel chromatin structure.
The donor site from where the transposon is excised is either degraded or...
The donor site from where the transposon is excised is either degraded or...
17.4K
02:10Translesion DNA Polymerases
11.2K
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...
11.2K
01:43Sustainable Development
15.1K
As the human population continues to grow and use resources, we must be mindful of our planet’s natural limits. Sustainable development provides a pathway to maintain and improve human life now while also ensuring that future generations will have the resources that they need. The long-term success of sustainability efforts rests on understanding the interplay between human actions and ecological systems.
15.1K