解开生殖系和soma中的钟形突变的来源
Natanael Spisak1, Marc de Manuel1, William Milligan1
1Department of Biological Sciences, Columbia University, New York, United States.
bioRxiv : the preprint server for biology
|September 25, 2023
概括
两个无处不在的突变特征,SBS特征1和SBS特征5,显示了与年龄相关的积累. SBS签名1与细胞分裂率有关,而SBS签名5与DNA修复错误有关,揭示了这些"钟形"突变的独特起源.
科学领域:
- 遗传学 是一个遗传学.
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 突变率因细胞类型而异,影响基因组稳定性.
- 单基替代 (SBS) 签名用于识别变种过程.
- 两个无处不在的签名,SBS1和SBS5,表现出年龄依赖的积累 ('钟式'行为).
研究的目的:
- 调查驱动与年龄相关的SBS1和SBS5.5积累的独特潜在机制.
- 区分细胞分裂速率和DNA损伤/修复作为时钟式突变的来源.
主要方法:
- 开发一个包含DNA复制错误,未修复的损伤和修复错误的数学模型.
- 分析不同细胞类型 (soma,男性/女性生殖系) 的突变积累率.
- 细胞系中变异速率的比较,具有不同分裂速率的细胞系.
主要成果:
- SBS签名1积累与细胞分裂率相关,特别是在快速分裂的细胞中.
- SBS签名1显示神经元转移后的神经元的增加最小,女性生殖系的增加有限.
- 随着时间的推移,SBS签名5在所有细胞类型中累积起来,不论分裂速度如何,涉及DNA修复过程.
结论:
- SBS签名1的时钟式行为主要是由以相对固定的速度发生的DNA复制驱动的.
- SBS签名5的时钟式行为独立于细胞分裂,可能源于DNA修复错误.
- 这两个无处不在的钟形突变特征有着不同的起源:细胞分裂率和DNA损伤/修复率.
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