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Published on: April 11, 2011
hnRNP 蛋白质促进Drosophila对规则转录的顶端细胞质运输和定位
S Lall1, H Francis-Lang, A Flament
1Developmental Genetics Laboratory, Imperial Cancer Research Fund, London, United Kingdom.
Cell
|July 31, 1999
概括
德洛索菲拉对规则基因转录需要核蛋白质才能在胚胎中适当地定位. 单独的细胞质运输是不够的,强调了核-细胞质相互作用在基因调节中的作用.
科学领域:
- 发育生物学是发展生物学.
- 分子遗传学 分子遗传学
- 细胞生物学 细胞生物学
背景情况:
- 众所周知,Drosophila melanogaster胚胎中的对规则基因转录位于核的核上.
- 这种局部化对于胚胎细分和发育至关重要.
- 潜在的机制包括矢量核出口或细胞质运输.
研究的目的:
- 调查Drosophila胚胎中对规则转录的顶端局部化背后的机制.
- 确定细胞质机制或核相互作用是否负责转录向.
主要方法:
- 在Drosophila胚胎中微注射光标记的fushi tarazu (ftz) 转录.
- 在注射之前,用核提取物 (Drosophila或人类) 处理成绩单.
- 使用显微镜观察转录本地化模式.
- 评估微管子对运输的依赖性.
主要成果:
- 裸体Ftz转录未能以光环局部化,表明单独的细胞质机制是不够的.
- 对核提取物的预暴露导致了快速,特异性,微管体依赖的传输.
- 有证据表明鱼 (Hrp40) 异质核核核糖核蛋白 (hnRNP) 的参与.
- 在转录本地化中hNRNP蛋白质的作用是进化保守的.
结论:
- 在Drosophila胚胎中,apical转录本地化不仅仅是一个细胞质过程.
- 核伙伴蛋白对于将转录物向它们的角目的地至关重要.
- 细胞质局部化机制可能会识别与核蛋白结合的转录.
- 这种涉及hNRNP的机制在物种之间得到保护.
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