Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Brigham and Women's Hospital, Harvard Medical School, Harvard Initiative for RNA Medicine, Boston, MA 02115, USA.
Biomolecules. 2020 Jun 27;10(7):969. doi: 10.3390/biom10070969.
The cellular response to changes in the surrounding environment and to stress requires the coregulation of gene networks aiming to conserve energy and resources. This is often achieved by downregulating protein synthesis. The 5' Terminal OligoPyrimidine (5' TOP) motif-containing mRNAs, which encode proteins that are essential for protein synthesis, are the primary targets of translational control under stress. The TOP motif is a cis-regulatory RNA element that begins directly after the m7G cap structure and contains the hallmark invariant 5'-cytidine followed by an uninterrupted tract of 4-15 pyrimidines. Regulation of translation via the TOP motif coordinates global protein synthesis with simultaneous co-expression of the protein components required for ribosome biogenesis. In this review, we discuss architecture of TOP mRNA-containing ribonucleoprotein complexes, the principles of their assembly, and the modes of regulation of TOP mRNA translation.
细胞对周围环境变化和应激的反应需要对基因网络进行协同调控，目的是保存能量和资源。这通常通过下调蛋白质合成来实现。含有 5'端寡嘧啶（5' TOP）基序的 mRNA 编码的蛋白质对于蛋白质合成是必不可少的，它们是应激下翻译调控的主要靶标。TOP 基序是一个顺式调控 RNA 元件，它直接位于 m7G 帽结构之后，包含标志性的不变 5'-胞嘧啶，其后是连续的 4-15 个嘧啶。通过 TOP 基序对翻译的调节与核糖体生物发生所需的蛋白质成分的同时共表达相协调，从而协调全局蛋白质合成。在这篇综述中，我们讨论了含有 TOP mRNA 的核糖核蛋白复合物的结构、它们的组装原则以及 TOP mRNA 翻译的调控模式。
