蛋白Farnesyl转移酶和Geranyl转移酶共享一个共同的α子单元
M C Seabra1, Y Reiss, P J Casey
1Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas 75235.
Cell
|May 3, 1991
概括
哺乳动物的前转移酶,法转移酶和基拉尼尔基拉尼尔转移酶共享一个共同的α子单元. 不同的β子单元决定了这些必需酶的不同蛋白质特异性.
科学领域:
- 分子生物学分子生物学
- 酶学 是一种酶学.
- 蛋白质前化 蛋白质前化
背景情况:
- 哺乳动物的法内赛尔转移酶对于修改p21ras蛋白质具有法内赛尔组至关重要.
- 这种酶复合体由α和β子单元组成,已知β子单元结合p21ras.
- 精确的子单元组成和 prenyltransferases 的共享组件仍然是一个研究领域.
研究的目的:
- 为了研究哺乳动物法内赛尔转移酶和相关的前转移酶的亚单元组成.
- 为了确定Farnesyltransferase的α子单元是否与其他化酶共享.
- 阐明不同prenyltransferases之间的基质特异性和结构关系.
主要方法:
- 使用凝过和离子交换染色学进行酶净化和表征.
- 使用抗体对抗Farnesyltransferase的α子单元的免疫沉和免疫阻塞.
- 对Farnesyl转移酶和Geranyl转移酶的蛋白质受体特异性的分析.
主要成果:
- 法尔内赛尔转移酶的α子单元与另一种先转移酶共享,该前转移酶将与Ras相关的蛋白质结合.
- 虽然表现出相似的分子量,但这两种酶可以通过染色学分离.
- 对α子单元的抗体识别了两种酶,证实了子单元的同源性.
- 对于分别法尔内西转移酶和格拉尼尔格拉尼尔转移酶,观察到明显的COOH终端氨基酸偏好 (甲胺/胺与白氨酸).
结论:
- 哺乳动物的法内西尔转移酶和格拉尼尔格拉尼尔转移酶是不同的异构酶.
- 这两种酶都有一个共同的α子单元,但具有不同的β子单元.
- 这种共享的子单元架构允许多种不同的蛋白质前化通路.
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