通过重建人类线粒体的末端连接来工程 mtDNA 删除
bioRxiv : the preprint server for biology
|October 28, 2024
概括
科学家在人类细胞中设计了特定的线粒体DNA (mtDNA) 删除,揭示了75%的删除值,导致严重的细胞功能障碍. 这一突破使mtDNA删除疾病的更好的建模和潜在的治疗开发成为可能.
科学领域:
- 细胞生物学 细胞生物学
- 遗传学 遗传学 是一个
- 分子生物学分子生物学
背景情况:
- 线粒体DNA (mtDNA) 突变会导致严重疾病,但在人类细胞中进行大规模的mtDNA删除仍然具有挑战性.
- 以前的进展允许基替代和突变mtDNA的去除,但不允许创建疾病相关的删除.
研究的目的:
- 开发一种用于工程特定的大规模mtDNA删除人类细胞的新方法.
- 创建和描述一组具有不同级别mtDNA缺失的同源细胞系.
- 为了研究mtDNA删除的细胞和分子后果.
主要方法:
- Prokaryotic 末端结合 (EJ) 机制和向内核酶 (mito-EJ 和 mito-ScaI) 的协同表达,以设计 mtDNA 删除.
- 克隆细胞系的生成,在整个异质体的全谱中~3.5kb的mtDNA删除.
- 细胞表型的分析,包括OXPHOS蛋白水平,代谢功能和生长.
- 单细胞多原子分析以确定核基因表达变化.
主要成果:
- 成功生成了一组具有特定mtDNA删除和受控异质体水平的人类细胞系.
- 确定了大约75%被删除基因组的关键异质体值,超出了OXPHOS枯竭,代谢中断和生长受损.
- 在对mtDNA删除的反应中发现了两种不同的核基因放松调节模式:一种是在值触发的,另一种则逐渐响应越来越多的异质体.
结论:
- 线粒-EJ和可编程核酶的共同表达是建模mtDNA删除疾病的强大工具.
- 已建立的细胞系面板为研究mtDNA删除的影响提供了宝贵的资源.
- 这种方法可以指导对线粒体肌肉病变和与年龄有关的疾病的治疗策略的开发.
相关概念视频
Fixing Double-strand Breaks
12.4K
The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
12.4K
Homologous Recombination
50.2K
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...
50.2K
Mismatch Repair
4.8K
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...
4.8K
Animal Mitochondrial Genetics
7.5K
Among all the organelles in an animal cell, only mitochondria have their own independent genomes. Animal mitochondrial DNA is a double-stranded, closed-circular molecule with around 20,000 base pairs. Mitochondrial DNA is unique in that one of its two strands, the heavy, or H, -strand is guanine rich, whereas the complementary strand is cytosine rich and called the light, or L, -strand. Compared to nuclear DNA, mitochondrial DNA has a very low percentage of non-coding regions and is marked by...
7.5K
Base Excision Repair
22.1K
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...
22.1K
Nucleotide Excision Repair
36.9K
Overview
36.9K


