在四个鱼种群中独立演变的耐污染性在很大程度上是由少数变种的大效应解释的
Jeffrey T Miller1,2, Bryan W Clark3, Noah M Reid4
1Department of Environmental Toxicology, Center for Population Biology, Coastal and Marine Sciences Institute University of California, Davis Davis California USA.
Evolutionary applications
|January 31, 2024
概括
鱼的抗污染能力的快速演变是由一些控制发育毒性的大效应基因驱动的. 然而,对复杂污染物的更广泛的耐药性可能涉及更多的遗传因素.
科学领域:
- 进化遗传学的进化遗传学
- 环境毒理学环境毒理学
- 生态生态学 生态生态学
背景情况:
- 人类改变的环境通过强大的自然选择推动了快速的进化.
- 了解适应污染的遗传基础对于预测物种反应至关重要.
- 城市河口的Fundulus killifish为研究对污染物的进化抵抗提供了一个模型.
研究的目的:
- 研究Fundulus killifish中对多二-126 (PCB-126) 发育毒性的进化耐药性的基因架构.
- 确定特定的定量特征位点 (QTL) 和与污染抵抗相关的候选基因.
- 为了比较多个独立进化的种群中耐药性的遗传基础.
主要方法:
- 使用RAD-seq在多个来自抗污染种群的鱼家族中的定量特征位点 (QTL) 映射.
- 胚胎暴露于有毒物质PCB-126以评估发育障碍.
- 在野生种群中分析共享的QTL和自然选择的签名.
主要成果:
- 对PCB-126发育毒性的耐药性在很大程度上是由一个到两个具有大效果的QTL位点解释的.
- 在QTL中确定了候选基因,调节酸受体 (AHR) 信号传递.
- 一个QTL在四个种群中共享,另一个在三个种群中共享,表明保存的遗传机制.
- 一个QTL显示了最近自然选择的强有力的证据,而另一个则没有.
结论:
- 快速进化对PCB-126发育毒性的耐药性在鱼中是由一些具有很大影响力的基因控制的.
- 保存的QTL表明了污染抵抗的常见遗传途径.
- 虽然发育性耐药性很简单,但对复杂污染物混合物的综合性耐药性可能在遗传上更复杂.
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