一个HIF独立的氧气敏感通道用于控制胆固醇合成
Anna S Dickson1, Tekle Pauzaite1, Esther Arnaiz1,2
1Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Jeffrey Cheah Biomedical Centre, Department of Medicine, University of Cambridge, Cambridge, CB2 0AW, UK.
Nature communications
|August 9, 2023
概括
胆固醇的合成依赖于氧气. 这项研究揭示了哺乳动物对氧气敏感的新途径,涉及醇调节元素结合蛋白2 (SREBP2) 的降解,这影响了癌细胞对胆固醇的依赖.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- 胆固醇生物合成是细胞膜关键的依赖氧气的途径.
- 菌表现出依赖氧气的固醇生产,触发类似于缺氧诱导因子 (HIF) 的转录反应.
- 在元动物中存在类似途径的存在仍然未被探索.
研究的目的:
- 为了研究类似的氧气敏感通路是否调节哺乳动物的胆固醇合成.
- 确定涉及这一途径的关键监管机构和机制.
主要方法:
- 鉴定醇调节元素结合蛋白2 (SREBP2) 作为一种对氧敏感的调节剂.
- 在低氧条件下对SREBP2降解的研究.
- 鉴定MARCHF6作为控制SREBP2稳定性的泛素结合酶.
- 在低氧状态下对他类药物的细胞反应的分析.
主要成果:
- 固醇调节元件结合蛋白2 (SREBP2),是哺乳动物固醇生产的关键转录因子,对氧气敏感.
- 在缺氧期间,SREBP2降解发生,独立于HIFs,取代正常的固醇感应.
- 在缺氧中被NADPH激活的MARCHF6被确定为SREBP2.2的主要泛素酶.
- 缺氧诱导的SREBP2降解通过促进外源胆固醇的吸收来保护细胞免受他类药物诱导的死亡.
结论:
- 在哺乳动物中发现了一种通过SREBP2降解来调节胆固醇合成的新型氧敏感通路.
- 这种途径解释了固体器官瘤中的胆固醇辅变异.
- 这些发现突出了SREBP2作为理解胆固醇代谢和癌症生物学的关键目标.
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