在 dictyostelium discoideum 中的糖蛋白生物合成:与蛋白质结合的糖的发育调节
Cell
|September 1, 1984
概括
迪西奥斯泰利姆迪斯科伊德姆糖蛋白的加工过程随着发育阶段的变化而变化. 早期阶段添加糖,硫酸盐和酸盐,而晚期阶段则根据细胞信号的影响修剪并添加糖.
科学领域:
- 细胞和分子生物学 细胞和分子生物学
- 发展生物学 发展生物学
- 葡萄糖生物学 葡萄糖生物学
背景情况:
- 在Dictyostelium discoideum中,糖蛋白N连接的寡糖生物合成始于从脂质载体转移的前体糖.
- 橄糖的加工高度依赖于生物体的发育阶段.
研究的目的:
- 在D. discoideum的早期和晚期发育过程中调查糖蛋白加工的独特途径.
- 确定细胞间接触和循环AMP (cAMP) 信号在调节这些处理通路中的作用.
主要方法:
- 在不同发育阶段 (早期与晚期) 的D. discoideum细胞中分析糖蛋白加工.
- 对细胞进行实验性操纵 (在摇中饥饿),以模仿发育线索.
- 观察糖结构的变化,包括添加福克,硫酸盐和酸盐,以及对前体糖进行修剪.
主要成果:
- 早期的开发加工保留了高曼诺结构,并添加了诸如糖,硫酸盐和酸盐等修改.
- 这些早期的处理反应在细胞聚合时就消失了.
- 晚期开发加工大量削减了前体,并将糖添加到外围的糖单元中.
- 这些后期的修改与细胞尖的形成相吻合.
结论:
- 在D. discoideum的发育过程中,有两种不同的糖蛋白加工酶被序列表达.
- 细胞间接触和cAMP信号似乎足以触发这些替代处理途径的受控表达.
- 发育阶段和细胞信号传递是糖蛋白N结合的寡糖化物处理的关键调节者.
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