一个特定于Krev-1蛋白的GTPase激活蛋白的分子克隆p21rap1
B Rubinfeld1, S Munemitsu, R Clark
1Cetus Corporation, Emeryville, California 94608.
Cell
|June 14, 1991
概括
研究人员发现了一种针对rap1/Krev-1的新型GTPase激活蛋白 (GAP). 这种rap1GAP表达不广泛,在胎儿组织和特定瘤细胞系中表达更高.
科学领域:
- 分子生物学分子生物学
- 细胞信号传递 细胞信号传递
背景情况:
- 拉普1/克雷夫-1基因编码了一种与拉斯相关的蛋白质,该蛋白质参与抑制瘤转化.
- GTPase激活蛋白 (GAPs) 调节ras相关蛋白质的活性.
研究的目的:
- 为了识别和描述特定于rap1/Krev-1基因产物的一种GTPase激活蛋白 (GAP).
- 为了确定这本小说的表达模式,rap1GAP.
主要方法:
- 从牛脑中净化一个88kDa的GTPase激活蛋白 (GAP).
- 用部分氨基酸序列从人类大脑图书馆中分离出3.3kb的cDNA.
- 在昆虫Sf9细胞中表达cDNA.
- 北方和西部的抹黑分析用于表达式分析.
主要成果:
- 净化了rap1GAP,证实了它对p21rap1 GTPase的特定活性.
- 隔离的cDNA在昆虫细胞中表达了一个功能性的rap1GAP (85-95kDa).
- 拉普1GAP的推断的氨基酸序列没有与已知的ras-specific GAPs显示同质性.
- 发现rap1GAP表达受到限制,胎儿组织和特定瘤细胞系 (SK-NEP-1,SK-MEL-3) 的最高水平.
结论:
- 一种新型的rap1GAP已经被识别和描述.
- 这种rap1GAP在规范p21rap1方面发挥着特定的作用.
- 受到限制的表达模式表明在发育和潜在的瘤发生过程中具有专门的功能.
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