Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China.
Beijing Advanced Center of RNA Biology (BEACON), Peking University, Beijing 100871, China.
Nucleic Acids Res. 2024 Aug 12;52(14):8165-8183. doi: 10.1093/nar/gkae478.
RNA polymerase II drives mRNA gene expression, yet our understanding of Pol II degradation is limited. Using auxin-inducible degron, we degraded Pol II's RPB1 subunit, resulting in global repression. Surprisingly, certain genes exhibited increased RNA levels post-degradation. These genes are associated with GPCR ligand binding and are characterized by being less paused and comprising polycomb-bound short genes. RPB1 degradation globally increased KDM6B binding, which was insufficient to explain specific gene activation. In contrast, RPB2 degradation repressed nearly all genes, accompanied by decreased H3K9me3 and SUV39H1 occupancy. We observed a specific increase in serine 2 phosphorylated Pol II and RNA stability for RPB1 degradation-upregulated genes. Additionally, α-amanitin or UV treatment resulted in RPB1 degradation and global gene repression, unveiling subsets of upregulated genes. Our findings highlight the activated transcription elongation and increased RNA stability of signaling genes as potential mechanisms for mammalian cells to counter RPB1 degradation during stress.
RNA 聚合酶 II 驱动 mRNA 基因表达,但我们对 Pol II 降解的理解有限。我们使用了生长素诱导的降解结构域,降解了 Pol II 的 RPB1 亚基,导致了全局抑制。令人惊讶的是,某些基因在降解后表现出 RNA 水平的增加。这些基因与 GPCR 配体结合有关,其特征是暂停较少,包含多梳结合的短基因。RPB1 降解全局增加了 KDM6B 的结合,但不足以解释特定基因的激活。相比之下,RPB2 降解几乎抑制了所有基因,同时伴随着 H3K9me3 和 SUV39H1 占据的减少。我们观察到 RPB1 降解上调基因的 Pol II 磷酸化 Ser2 和 RNA 稳定性的特异性增加。此外,α-鹅膏蕈碱或 UV 处理导致 RPB1 降解和全局基因抑制,揭示了上调基因的亚群。我们的研究结果强调了信号基因的激活转录延伸和增加的 RNA 稳定性,这可能是哺乳动物细胞在应激期间应对 RPB1 降解的潜在机制。