亨森节点的细胞运动在小中建立左/右不对称的基因表达
Jerome Gros1, Kerstin Feistel, Christoph Viebahn
1Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
概括
小胚胎通过在节点附近的细胞重新排列来建立左/右身体不对称性. 这种运动会影响基因表达,产生不对称的领域并打破对称性.
科学领域:
- 发育生物学是发展生物学.
- 胚胎学 胚胎学
- 分子生物学分子生物学
背景情况:
- 脊椎动物的左/右 (L/R) 解剖不对称性源于胃流动过程中的分子事件.
- 在胚胎中确立L/R不对称的确切机制仍然不清楚.
- 在L / R轴定义的早期步骤并非在物种中普遍保留.
研究的目的:
- 为了研究最早的事件定义左/右轴在胚胎.
- 为了阐明基底的分子机制L/R对称性破裂在小.
- 了解如何建立不对称的基因表达模式.
主要方法:
- 在胃流动期间,胚胎内细胞运动的分析.
- 追踪表达特定基因的细胞群,包括声波刺 (Shh) 和纤维细胞生长因子8 (Fgf8).
- 研究细胞移位和基因表达模式之间的关系.
主要成果:
- 在小胚胎中发生不对称的细胞重组,导致细胞在节点周围向左移动.
- 表达声波刺 (Shh) 和纤维细胞生长因子8 (Fgf8) 的细胞的相对位移至关重要.
- 这些细胞运动被动地为Shh和Fgf8.8建立了不对称的表达域.
结论:
- 细胞重组,而不是仅仅是内在的分子编程,在启动小的L / R不对称性中起着关键作用.
- 通过细胞运动被动建立不对称的基因表达域提供了打破L/R对称性的替代策略.
- 这一发现为脊椎动物中L / R轴确定保持和分离的机制提供了新的见解.
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