质静止素的氨基终端序列直接向细胞内,但不处理特异性
K A Sevarino1, P Stork, R Ventimiglia
1Department of Medicine, New England Medical Center Hospital, Boston, Massachusetts 02111.
Cell
|April 7, 1989
概括
细胞因子,而不是前体序列,决定了体静止素的处理. 鼠前益生态素 (rPPSS) N端残留物纠正鱼前益生态素-2 向哺乳动物细胞中的缺陷.
科学领域:
- 内分泌学 在内分泌学.
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 鼠的前前质静止素 (rPPSS) 产生体静止素-14和体静止素-28.
- 鱼群岛产生这些的明显前体 (a(I) PPSS,a(II) PPSS).
- 之前已经观察到鱼前体的差异化加工.
研究的目的:
- 调查鱼前前素-1和-2.2之间的差异化加工的基础.
- 确定细胞因子或前体序列是否决定体静止素的处理模式.
- 在前体中确定负责正确准和处理的区域.
主要方法:
- 被感染的哺乳动物内分泌细胞系与鱼前前质素-1 (a(I) PPSS) 和-2 (a(II) PPSS) 表达载体.
- 在哺乳动物细胞中分析了两种鱼前体的加工模式.
- 构建并表达了一种混合蛋白质,将大鼠前前质素 (rPPSS) 元素与鱼前质素-2融合.
主要成果:
- 在哺乳动物细胞中,a(I) PPSS和a(II) PPSS都进行了相同的处理,这表明细胞因子控制了处理.
- 尽管加工地点相似,但未经加工的鱼质素-2被构成性地分泌出来.
- 一种混合蛋白质与rPPSS N-终端残留物融合到a(II) PPSS被正确处理并通过受调节的途径分泌.
结论:
- 细胞因素,而不是固有的前体差异,决定了体静止素的处理模式.
- 鼠类前益生菌的N-终端78残留物含有适当向和处理的信号.
- 这些发现阐明了差异性索马托斯坦素前体加工的基础分子机制.
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