哺乳动物前额的发育起源
Paul P R Iyyanar1, Chuanqi Qin2, Nirpesh Adhikari1
1Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.
Developmental biology
|July 31, 2023
概括
研究人员追溯了前骨的起源,这是一个关键的骨. 他们发现,小鼠胚胎中的前鼻外细胞形成了前骨,证实了它在胚胎中的进化路径.
科学领域:
- 面生物学和发育遗传学.
- 进化的发育生物学 (Evo-Devo).
- 哺乳动物胚胎学和骨发育.
背景情况:
- 前的进化起源,一个关键的上骨在羊动物,仍然是争论的.
- 之前的研究表明,与其他脊椎动物相比,哺乳动物前额的胚胎起源不同.
- 缺乏工具来追踪哺乳动物面部发育中前鼻腔外膜的贡献,阻碍了进展.
研究的目的:
- 为了研究胚胎前鼻外膜对小鼠前骨形成的贡献.
- 在哺乳动物面部发育过程中开发和利用一种遗传工具来追踪前鼻外膜的血统.
- 为了澄清前额的发育起源及其在胚胎动物中的进化同质性.
主要方法:
- 一个新的Alx3CreERT2敲入鼠标线路的生成和表征,用于他莫西芬诱导的血统追踪.
- 使用Rosa26mTmG记者小鼠可视化CRE介导重组后的细胞系.
- 在特定的胚胎阶段 (E7.5-E10.5) 给予他莫西芬,以标记前鼻和上介质.
- 从胚胎阶段 (E9.5) 到产后发育 (E16.5) 的血统追踪,以追踪细胞命运.
- 一个Dlx1-Cre BAC转基因小鼠线的表征,以追踪大介质贡献.
主要成果:
- 在老鼠早期面部形态发生过程中,ALX3基因表达特异于前鼻外鼻膜,而不是大膜膜.
- 托莫西芬治疗Alx3CreERT2/+;Rosa26mTmG/+胚胎的具体标记是前鼻间基,但不是上间基.
- 血统追踪表明,Alx3标记的前鼻介质细胞分化为骨质母细胞,形成前骨.
- Dlx1-Cre标记的上介质对上骨和相邻的软组织有所贡献,但不是前骨.
结论:
- 胚胎前鼻外膜是小鼠前骨的直接发育来源.
- 这项研究为前额的起源提供了明确的证据,解决了面生物学中长期存在的问题.
- 这些发现证实了前额的进化保护和对母乳动物的同质性,这一点得到了遗传血统追踪的支持.
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