保存的囊蛋白阻止了粘素Cys域的C-曼诺基化
Marco Darius Albers1, Birgit Tiemann1, Jonas Till Kaynert1
1Institute of Clinical Biochemistry, Hannover Medical School, Germany.
The FEBS journal
|May 6, 2024
概括
氨酸在氨酸氨酸域 (CysDs) 中的氨酸残留物阻止了WxxW动机的C-mannosylation. 突变这些囊蛋白使C-mannosylation成为可能,揭示了这一重要的翻译后修饰的新型调节机制.
科学领域:
- 生物化学 生化学
- 葡萄糖生物学 葡萄糖生物学
- 分子生物学分子生物学
背景情况:
- 粘素是粘液的关键组成部分,具有O-糖化联重复和富含氨酸的域 (CysDs).
- CysDs含有保存的囊蛋白和WxxW动机,这是托C-mannosylation的潜在位置.
- 以前的研究表明CysDs是C-mannosylation目标,但缺乏直接证据.
研究的目的:
- 为了研究人类粘蛋白CysDs.的C-曼诺基化状态.
- 确定保存的氨酸残留物在调节WxxW基因的C-mannosylation中的作用.
- 为了比较粘膜中的CysD C-mannosylation与其他蛋白质 (如CILP1.1) 相比.
主要方法:
- 人类粘素CysDs和CILP1CysD在中国仓鼠卵巢 (CHO) 细胞中的重组表达.
- 氨酸残留物和WxxW动机的局部定向突变发生.
- 质谱分析以评估C-mannosylation状态.
主要成果:
- 再组合粘素CysDs在WxxW动机上显示微小或没有C-mannosylation.
- 氨酸CysDs中相邻的氨酸残留物的突变显著增强了C-mannosylation.
- 由于CILP1 CysD缺乏先前的半氨酸,因此被C-mannosylated,但引入半氨酸取消了这一点.
- 与WxxW动机相邻的保存的氨酸残留物抑制了其C-mannosylation.
结论:
- 在CysD中存在特定的氨酸残留物,可以在固体上阻碍或阻止WxxW基因的C-mannosylation.
- 这一发现揭示了一种新的机制,该机制调节了在氨酸丰富的域中氨酸C-mannosylation的调节.
- 了解这种调节对于理解粘素的结构-功能和相关病态至关重要.
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