在Xenopus的 oogenesis 过程中表达的含有 homeo-box 的基因
Cell
|November 1, 1984
概括
研究人员分离了一种新的Xenopus基因,具有同源域,类似于Drosophila基因. 该基因在卵细胞中具有很高的转录率,这表明它在早期胚胎细胞类型的确定中发挥了作用.
科学领域:
- 发育生物学 发展生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 家庭盒基因对于各种物种的胚胎发育至关重要.
- 之前对Xenopus homeobox基因的隔离突出了保存的发育途径.
- 像Antennapedia一样,Drosophila的同源基因作为理解基因功能的关键模型.
研究的目的:
- 报告Xenopus中第二个homeobox含有的基因的隔离和表征.
- 为了研究家庭主域序列的进化保存.
- 探索这个基因在早期的Xenopus胚胎发生中的潜在作用.
主要方法:
- 来自Xenopus laevis的基因隔离和测序.
- 具有已知的基因 (Drosophila Antennapedia,以前分离的青基因) 的家庭主体的同质分析.
- 在Xenopus卵细胞中分析基因转录水平.
主要成果:
- 隔离了一种新型的Xenopus基因,该基因具有homeo域.
- 高序列保护 (59/60氨基酸) 的家庭主体与Drosophila Antennapedia.
- 显著的保护 (54/60氨基酸) 与以前识别的青家庭盒基因.
- 在大型Xenopus卵细胞中大量转录该基因.
- 识别一个独特的carboxy-terminus与一个多重谷氨酸尾巴.
结论:
- 新分离的Xenopus基因代表了一个保存的含有homeobox的基因,可能参与发育.
- 它在卵细胞中的丰富转录表明它在母亲的基因表达中发挥了作用.
- 蛋白质产品可能在早期确定Xenopus.胚胎细胞类型中发挥关键作用.
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