种群大小与生殖寿命相互作用,以塑造生殖系突变率
Luke Zhu1, Annabel Beichman2, Kelley Harris2,3
1Department of Bioengineering, University of Washington, Seattle, WA 98195.
概括
几代时间较长的物种每代有更高的生殖基因突变率,但具有更有效的DNA修复机制. 这一反直觉的发现表明,选择平衡了跨物种的突变积累与修复效率.
科学领域:
- 进化生物学是进化的生物学.
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
背景情况:
- 突变率在物种之间表现出巨大的差异,受生长时间和有效种群大小的影响.
- 较大的有效种群大小可能会促进对影响DNA修复或细胞分裂的有害突变基因的选择.
- 突变率和DNA修复机制之间的关系在具有较长代期的多细胞生物中是复杂的.
研究的目的:
- 为了研究生成时间,生殖线突变率和多细胞物种中的DNA修复机制之间的关系.
- 测试假设,较长的生成时间放大了DNA损伤的适应性后果,驱动对增强修复的选择.
主要方法:
- 跨物种突变率的比较分析,具有不同的代代时间.
- 在不同发育阶段 (青春期前与生殖细胞) 检查生殖系突变的积累.
- 在生殖细胞和体组织中生成时间和突变率之间的相关性分析.
主要成果:
- 每一代的生殖基因突变率与生殖时间相反相关.
- 具有较长代期的物种表现出更有效的机制来避免和修复生殖细胞中的突变.
- 在青春期前,生殖线突变的积累显示出一个微弱的积极趋势,随着代代时间的增加.
结论:
- 长代时间可能会推动繁殖细胞中强大的DNA修复系统的选择,以减轻放大突变的后果.
- 这些发现表明,在更长寿命的突变积累和生殖系突变避免的效率之间存在一种权衡.
- 结果与长寿物种体内突变率较低的观察结果一致,表明选择是为了限制一生的突变负载.
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