尿素循环的调节是通过可逆的高静态度氨酸酸糖化来调节的
Ran Zhang1,2, Jingqi Fang1, Xueshu Xie1
1Buck Institute for Research on Aging, Novato, CA, USA.
Nature metabolism
|March 6, 2024
概括
氨酸酸化调节氨的新陈代谢. 删除SIRT5会增加ASS1上的化,降低尿素循环活性和氨耐受性.
科学领域:
- 生物化学 生物化学
- 代谢学 代谢学 代谢学
- 翻译后修改 翻译后修改
背景情况:
- 氨酸糖化是一种参与代谢调节的翻译后修饰.
- 方法上的挑战阻碍了识别具有功能意义的木化位点.
- lysine succinylation 的精确生物作用在很大程度上仍未确定.
研究的目的:
- 在小鼠肝脏中量化氨酸糖化固态度.
- 确定高影响化场所及其监管机制.
- 阐明 lysine succinylation 在氨基代谢中的功能重要性.
主要方法:
- 使用稳定同位素标记和数据独立采集质谱法.
- 在小鼠肝脏样本中量化了氨酸糖化固态度.
- 使用局部定向突变发生和代谢学分析来评估功能影响.
主要成果:
- 鉴定出了几个高静态度的氨酸糖化位点,特别是在缺少desuccinylase SIRT5.5的情况下.
- 酸氨酸合成酶 (ASS1),一种尿素循环酶,含有SIRT5调节的高静态度化位.
- 在ASS1中关键氨酸位点的突变以模仿糖化显著降低了其酶活性.
- 缺少SIRT5会导致尿素循环功能受损,肝脏对氨的耐受性降低,野生型ASS1可逆效应,但非突变ASS1.
结论:
- 氨酸酸化在功能上对氨酸代谢至关重要.
- SIRT5通过脱化对ASS1活动的调节起着关键作用.
- 针对性地识别高静态度化位点对于理解其生物相关性至关重要.
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