控制人类PAN2-PAN3死亡酶复合物的多A尾长特异性的机制
Jana C Albrecht1, Timo Reitinger1, Jérôme Basquin1
1Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany.
Cell reports
|November 23, 2025
概括
人类的PAN2-PAN3复合体缩短了信使RNA (mRNA) 上的长多A尾. 研究人员发现这种死亡酶具有更长的结合路径,这解释了它对哺乳动物mRNA长度的适应.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 是一个遗传学.
背景情况:
- 细胞mRNA的寿命由多甲缩短和多甲结合蛋白去除来调节.
- 人类PAN2-PAN3复合体通过缩短与PABPC1.1结合的长多 (A) 尾来启动死乙烯化.
- PAN2-PAN3和PABPC1在各物种中都存在,但人类适应较长的多样性尾巴的情况尚不清楚.
研究的目的:
- 研究人类PAN2-PAN3复合体如何识别和处理哺乳动物mRNA中发现的较长的多元A尾.
- 在较长的基板上阐明人类死亡酶增强活性的结构基础.
主要方法:
- 开发了一种合成长同型聚合物多分子ARNA (长达240nT) 的方法.
- 在实验室中使用合成聚甲基RNA和PABPC1.1复制和分析了人类死化活性.
- 使用单颗粒冷电子显微镜 (cryo-EM) 来确定与多A) -PABPC1核糖蛋白结合的PAN2-PAN3的结构.
主要成果:
- 人类PAN2-PAN3在较长的Poly(A) -PABPC1基质上表现出增强的死化活性,相比较短的基质.
- 冷EM分析显示,与其真菌对应物相比,人类PAN2-PAN3复合体的基质结合路径显著更长.
- 证明人类复合体可以有效地处理模仿哺乳动物mRNA长度的多A) 尾.
结论:
- 人类PAN2-PAN3中较长的基质结合路径的结构性适应解释了它对延长的多A尾部的作用能力.
- 这些发现为哺乳动物中死亡酶功能的共同进化和多A的尾巴长度调节提供了分子理由.
- 这项研究提供了对控制eukaryotesmRNA稳定性和基因表达的机制的见解.
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