c-Myc co-ordinates mRNA cap methylation and ribosomal RNA production.
c-Myc co-ordinates mRNA cap methylation and ribosomal RNA production.
复制标题
C-MYC坐标mRNA帽甲基化和核糖体RNA的产生。
DOI：
10.1042/bcj20160930
复制
发表时间：
2017-02-01
期刊：
影响因子：
--
通讯作者：
Cowling VH
中科院分区：
文献类型：
--
作者：
Dunn S;Lombardi O;Cowling VH
mRNA帽是在真核生物中添加到RNA pol II转录物的结构，其募集参与RNA加工、核输出和翻译起始的因子。RNA鸟嘌呤-7甲基转移酶（RNMT）-RNA激活微蛋白（RAM），mRNA帽甲基转移酶复合物，通过甲基化帽鸟苷完成基本功能mRNA帽结构，帽0。在这里，我们报告RNMT-RAM协调mRNA加工与核糖体生产。RNMT-RAM的抑制减少了45 S核糖体RNA（rRNA）前体的合成。RNMT-RAM是c-Myc表达所必需的，c-Myc是合成45 S rRNA的RNA pol I的主要调节因子。当RNMT-RAM被抑制时，c-Myc的组成型表达恢复rRNA合成，表明RNMT-RAM主要通过控制c-Myc表达来控制rRNA的产生。我们报告称RNMT-RAM被募集到核糖体DNA基因座，这可能有助于某些情况下的rRNA合成。
The mRNA cap is a structure added to RNA pol II transcripts in eukaryotes, which recruits factors involved in RNA processing, nuclear export and translation initiation. RNA guanine-7 methyltransferase (RNMT)–RNA-activating miniprotein (RAM), the mRNA cap methyltransferase complex, completes the basic functional mRNA cap structure, cap 0, by methylating the cap guanosine. Here, we report that RNMT–RAM co-ordinates mRNA processing with ribosome production. Suppression of RNMT–RAM reduces synthesis of the 45S ribosomal RNA (rRNA) precursor. RNMT–RAM is required for c-Myc expression, a major regulator of RNA pol I, which synthesises 45S rRNA. Constitutive expression of c-Myc restores rRNA synthesis when RNMT–RAM is suppressed, indicating that RNMT–RAM controls rRNA production predominantly by controlling c-Myc expression. We report that RNMT–RAM is recruited to the ribosomal DNA locus, which may contribute to rRNA synthesis in certain contexts.