随机无脊柱表达创造了视网膜马赛克,用于色彩视觉
Mathias F Wernet1, Esteban O Mazzoni1, Arzu Çelik1
1Center for Developmental Genetics, Department of Biology, New York University, 100 Washington Place, New York, New York 10003, USA.
Nature
|March 10, 2006
概括
果虫的二氧化碳受体无脊椎对于创建视网膜马赛克至关重要,对于色彩视觉至关重要. 它在R7细胞中的表达决定了ommatidia是否成为ommatidia.
科学领域:
- 神经科学是一个神经科学.
- 发展生物学 发展生物学
- 遗传学 是一个遗传学.
背景情况:
- 果虫的色彩视觉依赖于ommatidia内的R7和R8光受体细胞.
- 存在两种ommatidial亚型",白"和"黄色",由明显的Rhodopsin表达决定.
- 这些亚型是随机分布在视网膜上,类似于人类的光受体.
研究的目的:
- 为了确定控制Drosophila视网膜体亚型的静态形成的分子机制.
- 为了研究二氧化物受体在建立白和黄色的体马赛克中的作用.
主要方法:
- 对无脊椎 (ss) 突变的分析,观察对R7和R8细胞命运的影响.
- 在R7细胞中过度表达无脊椎细胞的研究,以评估其在命运决定中的充分性.
- 与罗多普辛表达相对,在化期间无脊椎表达的时间分析.
主要成果:
- 无脊柱体是形成形马赛克所必需的;无脊柱体突变体在R7和R8细胞中表现出统一的"白"命运.
- 在R7细胞中无脊柱表达的短暂爆发之前,罗多普辛表达,决定了基子类型.
- 无脊椎细胞的过度表达足以诱导"黄色"R7细胞命运,取代默认的"白"命运.
结论:
- 转录因子 Spineless 是既必要又足够的,以建立Drosophila.的随机形马赛克.
- 一个单一的转录因子,无脊柱体,控制了Drosophila彩色视觉所需的整个视网膜马赛克.
- 这一发现为感官马赛克形成的遗传调节提供了关键的见解.
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