The Mina and Everard Goodman Faculty of Life Sciences and Advanced and Nanotechnology Institute, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, 7610001, Israel.
Nat Commun. 2023 Nov 20;14(1):7462. doi: 10.1038/s41467-023-43263-6.
Trypanosomes are protozoan parasites that cycle between insect and mammalian hosts and are the causative agent of sleeping sickness. Here, we describe the changes of pseudouridine (Ψ) modification on rRNA in the two life stages of the parasite using four different genome-wide approaches. CRISPR-Cas9 knock-outs of all four snoRNAs guiding Ψ on helix 69 (H69) of the large rRNA subunit were lethal. A single knock-out of a snoRNA guiding Ψ530 on H69 altered the composition of the 80S monosome. These changes specifically affected the translation of only a subset of proteins. This study correlates a single site Ψ modification with changes in ribosomal protein stoichiometry, supported by a high-resolution cryo-EM structure. We propose that alteration in rRNA modifications could generate ribosomes preferentially translating state-beneficial proteins.
锥虫是一种原生动物寄生虫，在昆虫和哺乳动物宿主之间循环，并导致昏睡病。在这里，我们使用四种不同的全基因组方法描述了寄生虫两个生活阶段中 rRNA 上假尿嘧啶（Ψ）修饰的变化。CRISPR-Cas9 敲除所有四个 snoRNA 都会导致大 rRNA 亚基螺旋 69（H69）上的 Ψ 引导致死。单个 snoRNA 敲除 H69 上的 Ψ530 会改变 80S 单体的组成。这些变化仅特异性地影响一小部分蛋白质的翻译。这项研究通过高分辨率冷冻电镜结构，将单个位点 Ψ 修饰与核糖体蛋白化学计量的变化联系起来。我们提出，rRNA 修饰的改变可以产生优先翻译对状态有益的蛋白质的核糖体。
