MyoD DNA 结合域包含肌肉特定基因激活的识别代码
R L Davis1, P F Cheng, A B Lassar
1Department of Genetics, Hutchinson Cancer Research Center, Seattle, Washington 98104.
Cell
|March 9, 1990
概括
MyoD基本区域对于DNA结合和肌肉基因激活至关重要. 交换这个区域会阻止肌肉程序的激活,即使具有DNA结合能力.
科学领域:
- 分子生物学分子生物学
- 发展生物学 发展生物学
- 遗传学 是一个遗传学.
背景情况:
- 肌源性决定基因MyoD在肌肉发育中起着关键作用.
- 众所周知,MyoD的一个特定的60氨基酸域对其功能至关重要.
研究的目的:
- 确定MyoD域内负责特定序列DNA结合和肌性转换的特定区域.
- 调查螺旋-环-螺旋 (HLH) 动图和上游基本区域在MyoD功能中的作用.
主要方法:
- 用于取代MyoD基因的特定区域的局部定向突变发生.
- 进行了体外DNA结合试验,以评估序列特定的结合.
- 使用C3H10T1/2细胞进行了传染试验,以评估肌源性转化和肌肉特异性基因激活.
主要成果:
- 在HLH动机上游的一个高度基本的区域对于MyoD的体外DNA结合至关重要.
- 用Drosophila T4 achaete-scute蛋白质的类似序列替换helix1,helix2或MyoD循环并没有影响DNA结合或肌肉基因激活.
- 将MyoD基本区域替换为来自E12或T4achaete-scute蛋白的序列允许DNA结合,但取消了肌肉特异性基因激活.
结论:
- MyoD基本区域包含一个识别代码,该代码对肌肉特定基因激活至关重要.
- 单独对特定序列的DNA结合不足以触发肌肉发育程序; 需要基本区域的特定序列.
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