一个代谢推进器调节rDNA的表观遗传状态
Ingrid Grummt1, Andreas G Ladurner
1Department of Molecular Biology of the Cell II, German Cancer Research Center, DKFZ-ZMBH Alliance, Im Neuenheimer Feld 581, 69120 Heidelberg, Germany. i.grummt@dkfz-heidelberg.de
Cell
|May 20, 2008
概括
营养状况会影响细胞生长. 一项新的研究揭示了细胞能量水平如何通过涉及SIRT1,SUV39H1和核甲基因 (NML) 的复合体控制核糖体RNA基因沉默,确保细胞存活.
科学领域:
- 分子生物学分子生物学
- 细胞的新陈代谢
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 核糖体RNA (rRNA) 合成对于细胞生长至关重要,并且受到营养的可用性严格调节.
- 了解将细胞生理与基因表达联系起来的机制,对于理解细胞生存策略至关重要.
研究的目的:
- 阐明了将细胞能量状态与核糖体RNA基因的沉默联系在一起的机制.
- 为了识别参与调节rRNA基因在对营养线索的反应中形成 heterochromatin 的分子参与者.
主要方法:
- 研究了NAD(+) /NADH比在调节基因沉默中的作用.
- 描述了eNoSC复合体 (SIRT1,SUV39H1,NML) 在应对葡萄糖饥饿时的功能.
- 评估了改变能量状态对异性染色素形成和rRNA基因活性的影响.
主要成果:
- 由葡萄糖饥饿引起的改变NAD+/NADH比率被证明可以调节eNoSC复合物的沉默活性.
- 由SIRT1,SUV39H1和核甲基林 (NML) 组成的eNoSC复合体,调解细胞能量和异色染色体形成之间的联系.
- 在营养缺乏的情况下,这种调节途径有效地使rRNA基因沉默.
结论:
- 一种新的机制将细胞能量状态 (NAD+/NADH比) 与通过eNoSC复合体对rRNA基因的表观遗传沉默联系起来.
- 这种rDNA沉默的生理调节对于保持核细胞完整性和在营养应激期间促进细胞存活至关重要.
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