葡萄糖生成酶PCK2在内皮细胞的蛋白质稳定中具有非酶作用
Pauline de Zeeuw1,2,3, Lucas Treps1,2,4, Melissa García-Caballero1,2,5
1Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, KU Leuven, Leuven, B-3000, Belgium.
Communications biology
|May 23, 2024
概括
当葡萄糖稀缺时,内皮细胞 (ECs) 使用涉及PCK2的截断葡萄糖生成 (GNG) 途径. 这一途径支持生物合成,并意外地保持了蛋白质的稳定性,这对于EC生存和血管形成至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生化学
- 身体生理学 身体生理学
背景情况:
- 内皮细胞 (ECs) 主要利用糖解来获得能量.
- 葡萄糖生成 (GNG) 在ECs中的作用,特别是在营养缺乏的情况下,尚不清楚.
- 除了GNG之外,PCK2酶在EC中的功能在很大程度上尚未被探索.
研究的目的:
- 调查EC是否在缺乏葡萄糖的条件下进行GNG.
- 阐明PCK2在EC新陈代谢和蛋白质稳定中的作用.
- 确定PCK2对EC功能和血管发育的影响.
主要方法:
- 在不同的葡萄糖条件下分析EC中PCK2表达和活性.
- 利用基因沉默 (PCK2) 来评估代谢和蛋白静态变化.
- 研究未折叠的蛋白质反应,蛋白酶活性和自.
- 评估EC可行性和体外血管发芽试验.
主要成果:
- 缺乏葡萄糖的EC可以提高PCK2的调节,并使用使用乳酸和谷氨酸的截断GNG通路.
- 这一途径为血清素和甘氨酸脂生物合成提供中间体,支持氧化还原稳定和膜合成.
- 独立于GNG活动的PCK2沉默会损害未折叠的蛋白质反应和蛋白质稳定.
- PCK2 缺乏导致蛋白质聚合物的积累,EC 死亡和受损的血管发芽.
结论:
- 在葡萄糖剥夺期间,ECs利用PCK2-依赖的截断的GNG通路进行代谢支持.
- PCK2在维持内皮质蛋白质稳定中起着关键的非代谢作用.
- PCK2对于内皮细胞生存,功能和血管发育至关重要.
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