Ribosome Footprinting of WT and mutant yeast cells at different temperatures

We use ribosome footprinting to assess the gene expression changes occuring after 10 minutes of heat stress at either 40°C or 42°C compared to non-stressed yeast cells (30°C). We find that between 40°C and 42°C there is a shift in gene expression from the expression of genes harboring long and structured 5'UTRs to the expression of genes harboring thranscripts with short and unstructure 5'UTRs. We performed these experiments for WT yeast cells as well as for mutant yeast cells in which the RNA helicase Ded1 condensates at lower temperatures (Ded1-IDRm). We find upon comparing mutant and WT cells at 42°C, that Ded1-IDRm has increased expression of genes harboring unstructured 5'UTRs and decreased expression of genes harboring structured 5'UTRs.本研究采用核糖体印迹（ribosome footprinting）技术，以培养于30℃的未受应激酵母细胞为对照，分析酵母细胞经40℃或42℃热应激10分钟后发生的基因表达变化。研究发现，在40℃与42℃之间，基因表达模式发生显著转变：从偏好表达携带长且结构化5'非翻译区（5' untranslated region, 5'UTR）的基因，转向偏好表达携带短且非结构化5'UTR的转录本。本研究分别针对野生型（wild type, WT）酵母细胞，以及RNA解旋酶Ded1可在更低温度下发生凝聚的突变酵母细胞（Ded1-IDRm）开展了上述实验。通过对比42℃下的突变体与野生型细胞，本研究发现Ded1-IDRm细胞中携带非结构化5'UTR的基因表达量显著上调，而携带结构化5'UTR的基因表达量显著下调。