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Updated: Jul 19, 2025

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翻译调节实体的解码揭示了细胞衰老中异质的翻译缺陷模式
Angelos Papaspyropoulos1,2, Orsalia Hazapis1, Abdullah Altulea3
1Molecular Carcinogenesis Group, Department of Histology and Embryology, School of Medicine, National Kapodistrian University of Athens (NKUA), Athens, Greece.
Aging cell
|August 7, 2023
概括
细胞衰老涉及明显的翻译调节差异. 与其他衰老类型不同,癌基因诱导衰老 (OIS) 主要使用核糖体停滞,uORF/dORF模式和IRES元素.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 基因组学就是基因组学.
背景情况:
- 细胞衰老是一种不可逆转的细胞循环停止状态,伴有代谢变化.
- 不同的衰老类型 (复制性,压力诱导,瘤基因诱导) 呈现出独特的表型.
- 减少蛋白质合成是衰老的标志,但其跨子类型的潜在机制尚不清楚.
研究的目的:
- 研究翻译调节机制对各种衰老亚型中蛋白质合成缺陷的差异性贡献.
- 探索核糖体停滞,上游开放阅读框架 (uORFs) /下游开放阅读框架 (dORFs) 和内部核糖体进入点 (IRES) 元素在衰老中的作用.
主要方法:
- 来自已出版和实验来源的大型RNA-seq和Ribo-seq数据集的分析.
- 对复制性衰老 (RS),压力诱导衰老 (SIS) 和基因诱导衰老 (OIS) 的翻译调节模式的比较分析.
主要成果:
- 翻译调节机制与RS没有直接联系.
- uORF在SIS中得到了显著的丰富.
- 核糖体停滞,uORF/dORF模式和IRES元素在OIS中占主导地位,与Notch通路激活相关.
- 这些机制的程度与翻译缺陷水平直接相关.
结论:
- 细胞衰老中的主要翻译失调机制因发起刺激而有很大不同.
- 核糖体停滞,uORF/dORF和IRES元素的特定模式是OIS的特征,与Notch信号相关.
- 这项研究揭示了老化子集中翻译机制的关键,以前未知的差异.
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