后脑细分的霍克斯调节网络被保存到脊椎动物的底部
Hugo J Parker1, Marianne E Bronner2, Robb Krumlauf3
1Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA.
Nature
|September 16, 2014
概括
控制脊椎动物头部模式的基因调控网络,整合后脑细分和霍克斯基因表达,是古老的. 这项研究揭示了和无脊椎动物之间的调节元素和转录因子的深度保护,表明这种特征的早期起源.
科学领域:
- 发展生物学 发展生物学
- 进化生物学 进化生物学
- 遗传学 是一个遗传学.
背景情况:
- 脊椎动物的头部模式依赖于一个保存的基因调节网络,将后脑细分与Hox基因表达域联系起来.
- 非脊椎动物的带动物表现出嵌套的轴向霍克斯表达,但缺乏后脑细分,这表明发育策略的分歧.
- 海,一个没有的鱼,提供了一个独特的视角,脊椎动物的起源,由于其基底的遗传位置.
研究的目的:
- 调查海的Hox基因表达底层的调控网络及其与后脑细分的关系.
- 探索与和无脊椎动物之间头部模式相关的调节元素和转录因子的进化保存.
- 确定霍克斯基因表达与后脑细分的合是否是一种古老的脊椎动物特征.
主要方法:
- 利用一种新的工具,对有和没有的脊椎动物之间的调节元素进行跨物种的比较.
- 测试了来自各种体的调节区域,以检测它们在后脑中驱动细分记者表达的能力.
- 分析了对特定的转录输入的要求,例如Kreisler (Mafba) 和Krox20 (Egr2a),在鱼和斑马鱼中.
- 隔离和表征了一种保存的异构Hox2增强剂从Lamprey.
主要成果:
- 在有和没有的脊椎动物中证明了上游调节者的深度保护和增强元件的细分活性.
- 显示 gnathostome 调节区域可以在后脑中驱动细分记者表达,需要保存的转录输入.
- 证实鱼霍克斯基因表现出动态的,细分受限制的表达域.
- 鉴定了一种Lamprey Hox2增强剂,该增强剂驱动了2号和4号染色体中的细分表达.
结论:
- 霍克斯基因表达与后脑细分的结合是一种古老的特征,起源于脊椎动物血统的基础.
- 这种古老的调节机制很可能在脊椎动物进化的早期建立了具有定义的霍克斯代码的罗姆体区.
- 保存的调节元素和转录因子要求突出显示了脊椎动物头部发育的深刻进化历史.
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