缺少MCJ/DnaJC15可促进棕色脂肪组织的热生成
Beatriz Cicuéndez1,2, Alfonso Mora1,2, Juan Antonio López1,3
1Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain.
Nature communications
|January 13, 2025
概括
甲基化控制的J蛋白 (MCJ) 调节棕色脂肪组织 (BAT) 的热生成. 肥胖中较低的MCJ水平与增加的BAT活动有关,这表明MCJ是潜在的肥胖治疗目标.
科学领域:
- 线粒体生物学 线粒体生物学
- 肥胖研究的研究.
- 脂肪组织的新陈代谢.
背景情况:
- 肥胖是一个全球性的健康问题,需要更好地了解脂肪组织 (AT) 和它的线粒体.
- 在AT中线粒体功能障碍与代谢障碍有关.
- 特定线粒体蛋白在热生成中的作用仍然不完全理解.
研究的目的:
- 为了研究甲基化控制的J蛋白 (MCJ/DnaJC15) 在棕色脂肪组织 (BAT) 热生成中的功能.
- 在肥胖的背景下,探索MCJ对线粒体功能和形态学的影响.
- 阐明分子通路,包括eIF2α应激反应,参与MCJ介导的温度调节.
主要方法:
- 从肥胖和瘦人群的人类和小鼠脂肪组织样本中分析MCJ表达.
- 对MCJ淘汰赛 (MCJKO) 小鼠的表型特征,包括对BAT热生成的评估.
- 电子显微镜用于评估MCJKO小鼠中的线粒体形态.
- 蛋白质组分析以确定相互作用的蛋白质和通路.
- 在MCJKO小鼠体内通过CRISPR-Cas9调解eIF2α的删除,以评估其作用.
主要成果:
- 在肥胖期间,MCJ表达在脂肪组织中减少.
- MCJKO小鼠表现出增强的BAT热生成,即使没有UCP1.
- 在MCJKO小鼠中的线粒体形态类似于激活的BAT.
- 蛋白质组数据表明eIF2α介导的应激反应的参与.
- 在eIF2α被删除后,MCJKO小鼠中热生成的废除证实了它的关键作用.
结论:
- MCJ是棕色脂肪组织热生成的关键调节者.
- 减少MCJ表达有助于改变线粒体功能和增加肥胖的发热.
- eIF2α应激反应途径对于MCJ在BAT热生成中的作用至关重要.
- MCJ代表了管理肥胖的潜在治疗目标.
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