在缺乏基于piRNA的宿主防御的情况下,非自主元素的快速出现可能会阻止P元素入侵
Matthew Beaumont1,2, Divya Selvaraju1,2, Riccardo Pianezza1,2
1Institut für Populationsgenetik, Vetmeduni Vienna, Wien, Austria.
PLoS genetics
|August 20, 2025
概括
可转移元素 (TE) 可以伤害宿主或灭绝. 在果中,非自主性P元素出乎意料地超过了全长版本,在没有宿主防御的情况下阻止了TE的传播.
科学领域:
- 遗传学和基因组学
- 进化生物学
- 分子生物学
背景情况:
- 可转移元素 (TE) 对它们自身和宿主生物构成进化风险.
- 转基因侵袭可能导致宿主灭绝或转基因流失.
- 在Drosophila melanogaster中的P元素入侵是研究TE宿主动态的一个模型.
研究的目的:
- 研究D. melanogaster中P元素入侵的长期种群动态.
- 确定入侵可转移元素的新风险和进化结果.
- 了解驱动宿主群体中TE复制数的稳定机制.
主要方法:
- 在100代的实验D. melanogaster种群中监测P元素入侵动态.
- 分析 TE 副本数和识别自主与非自主插入类型.
- 评估宿主防御机制的存在和影响,例如piRNA通路.
主要成果:
- 由于基于piRNA的宿主防御,P元素拷贝数量最初增加,随后在大多数种群中稳定.
- 一个群体 (R2) 在没有piRNA防御的情况下在较低的副本数量下显示P元素稳定.
- 在R2中这种稳定归因于非自主P元素插入与内部删除的增多,超过了全长元素.
结论:
- 非自主性TE插入的出现可以意外地阻止TE的传播,避免对宿主进行防御.
- 这种非自主元素的扩散可能是特异体的进化死胡同.
- 这些发现解释了自然种群中内部删除的P元素的流行情况,并影响了TE的重新入侵潜力.
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