追踪状体索米特在半状体Ptychodera状体中的进化起源
Cindy Chou1, Ching-Yi Lin1, Che-Yi Lin1
1Institute of Cellular and Organismic Biology, Academia Sinica, 11529 Taipei, Taiwan.
Integrative and comparative biology
|April 18, 2024
概括
对于发育至关重要的状体,很可能是从它们进化祖先的类似结构进化而来的. 这项研究表明,半前和前之间存在同质性,揭示了共同的发育途径.
科学领域:
- 发育生物学 发展生物学
- 进化生物学 进化生物学
- 基因组学就是基因组学.
背景情况:
- 梅塔美里克索米特 (Metameric somites) 是带动物的一个决定性特征,但它们的进化起源仍然不清楚.
- 在两动物中,前腔体通过肠球体发展,需要纤维细胞生长因子 (FGF) 信号传递,这表明与脊椎动物中皮的潜在同质性.
- 研究状动物的姊妹群体Ambulacraria,是理解某种进化过程的关键.
研究的目的:
- 通过检查 Hemichordates 的同源结构来研究带状体的进化起源.
- 为了识别与前端结膜 (protocoel) 相关的调节基因和分子标记物,在Ptychodera flava.
- 为了比较半弦状细胞的发育过程和基因表达模式,半弦状细胞的协议与弦状细胞.
主要方法:
- RNA测序 (RNA-seq) 用于对Ptychodera flava protocoel.中的调节基因进行全面的选.
- 一种候选基因方法确定了已知的状索米特标记物的P. flava ortologs.
- 在现场杂交被用来分析这些候选基因在半弦状原生细胞中的表达模式.
主要成果:
- 通过RNA-seq识别了许多与中皮衍生原型相关的调节基因.
- 表达式分析显示,许多候选基因,与弦状体标记物的正系基因,在半弦状体原生细胞内被分隔.
- 半弦状原生细胞和前方状体共享类似的发育过程 (内细胞),信号通路 (FGF) 和基因表达模式.
结论:
- 建议半弦状原始细胞和前弦状前腔体是同源结构.
- 索米特很可能是从体体,FGF依赖性和分子分离的前体进化而来的,这些前体在体体的最后一个共同祖先中.
- 这一发现提供了关键的洞察力,可以了解状动物的身体计划和发育机制的早期演变.
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