概括
鼠类垂体细胞 (AtT-20) 可以处理和储存人类亲胰岛素,类似于它们的原生上腺皮质激素 (ACTH). 这表明,用于ACTH运输的细胞机械识别了其他前激素.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 内分泌学 在内分泌学.
背景情况:
- 众所周知,来自小鼠前垂体的ATT-20细胞系合成,处理,储存和释放上皮质激素 (ACTH).
- 了解激素的细胞内运输和处理机制对于各种生物过程至关重要.
研究的目的:
- 调查AtT-20细胞系的ACTH处理和储存机械是否能够识别和处理其他益激素.
- 确定ACTH前体的运输机制是否具有特异性或可以容纳异质前激素.
主要方法:
- 稳定转化AtT-20细胞与含有人类亲胰岛素cDNA的重组载体.
- 培养转变的ATT-20细胞和纤维细胞L细胞.
- 用分泌剂刺激细胞以诱导激素释放.
- 使用免疫试验测量和描述释放的胰岛素类物质和亲胰岛素.
主要成果:
- 转变的AtT-20细胞 (AtT-20ins4b/1) 储存了免疫反应性胰岛素,将亲胰岛素加工成更小的碎片,并在分泌器刺激时释放了类似胰岛素的物质.
- 纤维细胞L细胞,也转化,只分泌亲胰岛素,不储存它,并没有显示任何变化分泌率与 secretagogues.
- 从AtT-20细胞中释放加工的胰岛素样物质表明了特定的细胞内处理.
结论:
- 对于ACTH前体的ATT-20细胞系的细胞内运输和处理机制可以识别和处理其他益激素,如人类亲胰岛素.
- 这表明,负责亲激素分类和分泌的细胞机制存在一定程度的乱交.
- 这些发现表明,前体ACTH的运输系统不是严格的特异性,可以容纳不同的前激素基质.
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