氨酸对于巨细胞中特定颗粒蛋白酶的储存至关重要
D E Humphries1, G W Wong, D S Friend
1Department of Medicine, Boston University School of Medicine, and VA Medical Center, Massachusetts 02130, USA. Humphries.Donald_E@BOSTON.VA.GOV
Nature
|August 31, 1999
概括
肝素是一种重要的葡萄糖氨基酸甘氨酸,它调节着巨细胞中的蛋白酶水平. 这项研究揭示了肝素.
科学领域:
- 生物化学 生物化学
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
背景情况:
- 氨酸是哺乳动物中无处不在的葡萄糖氨基甘氨酸,主要存在于巨细胞颗粒中.
- 尽管进行了广泛的研究,但肝素的确切生理作用仍然难以捉摸.
- 乳腺细胞是关键的免疫细胞,参与过敏反应和炎症.
研究的目的:
- 为了研究肝素在哺乳动物中的生理功能.
- 确定肝素在瘤细胞蛋白酶调节中的作用.
- 阐明肝素影响巨细胞蛋白酶含量的机制.
主要方法:
- 通过破坏N-deacetylase/N-sulphotransferase-2基因,产生缺乏完全硫酸的转基因小鼠.
- 对转基因小鼠骨肌中的细胞颗粒的分析.
- 培养和分析从转基因小鼠骨髓中提取的乳腺细胞.
主要成果:
- 缺乏肝素的转基因巨细胞显示出甲基色素颗粒的缺乏.
- 这些巨细胞未能储存特定的蛋白酶 (mMCP-4,mMCP-5,mMC-CPA),但保留了mMCP-7.
- 来自转基因小鼠的培养性巨细胞也表现出减少的mMCP-5和mMC-CPA表达,尽管蛋白酶转录水平很高.
结论:
- 氨酸对于乳腺细胞内特定的正电荷蛋白酶的适当储存至关重要.
- 氨酸通过一个后翻译机制调节某些蛋白酶的水平.
- 这一发现澄清了巨细胞生物学和蛋白酶调节的一个关键方面.
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