Impact of chemical modification of non-coding RNAs on gene expression in S. pombe

细胞已经进化出许多不同的机制，通过这些机制它们确保对生命至关重要的基因的稳定表达，以及它们可以改变这些过程以适应环境条件和压力的复杂方案。许多这些机制和过程在整个进化过程中是高度保守的。使用单细胞真核生物来研究这些关键过程通常要简单得多，也更直接，我们可以从中推断出相关过程在高等真核生物（如人类）中是如何控制的。在我们提出的工作中，我们计划使用简单的酵母裂殖酵母来研究特定的化学反应如何有助于用于控制基因表达的细胞内机制的组分的稳定维持。更具体地说，我们建议研究一些保守的，但表征不佳的酶，负责化学修饰的RNA分子，包括基因表达基础设施的关键组成部分。 我们将研究的一类酶负责转移RNA（tRNA）的化学修饰，这些分子在所有生命形式的蛋白质合成中起着关键作用。这些酶被假设为促进tRNA稳定性并在tRNA质量控制中发挥作用，因此我们提出的工作将导致对细胞如何确保用于合成蛋白质的机器正确生成的新见解。 我们还计划研究另一类甲基转移酶，它们修饰其他类型的非编码RNA，但其确切功能和重要性还不清楚。 这些酶的进化保守性是不寻常的：它们存在于一些生物体中，但不存在于其他生物体中，尽管酶的已知靶标是通用的，对细胞生长至关重要。 通过研究这些RNA修饰酶及其在裂殖酵母中的靶点的进化保守性，我们将更好地理解生命是如何进化的，以促进用于表达基因的机器的稳健合成，以及确保正确完成的质量控制机制。这些机制在酵母中的阐明将有助于推断高等生物中的相关途径，并可能有助于产生新的基因工程工具，以及设计新的抗微生物剂。

Cells have evolved a number of diverse mechanisms by which they ensure the stable expression of genes that are critical to life, as well as complex schemes by which they can vary such processes in order to adapt to environmental conditions and stresses. Many of these mechanisms and processes are highly conserved throughout evolution. It is often then much simpler and more straight-forward to study these critical processes using single-celled eukaryotes from which we can then extrapolate insights into how related processes are controlled in higher eukaryotes, like humans. In our proposed work, we plan to use the simple yeast Schizosaccharomyces pombe to investigate how specific chemical reactions contribute to the stable maintenance of components of the intracellular machinery that are used to control gene expression. More specifically, we propose to study a number of conserved but poorly characterized enzymes that are responsible for the chemical modification of RNA molecules that comprise critical components of the gene expression infrastructure.  One class of enzymes we will study is responsible for the chemical modification of transfer RNAs (tRNAs), which are molecules that play critical roles in the synthesis of proteins in all life forms examined. These enzymes are hypothesized to promote tRNA stability and play a role in tRNA quality control, and so our proposed work will lead to new insights into how cells ensure that the machinery used to synthesize proteins is correctly generated.  We also plan to investigate another class of methyltransferases that modify other types of non-coding RNAs but whose precise function and importance are not well understood.  The evolutionary conservation of these enzymes is unusual: they are present in some organisms but not others, even though the known targets of the enzyme are universal and critically important to cellular growth.   By studying the evolutionary conservation of these RNA modification enzymes and their targets in Schizosaccharomyces pombe, we will arrive at a better understanding of how life has evolved to promote robust synthesis of the machinery used to express genes as well as the quality control mechanisms in place to ensure this is done correctly. The elucidation of these mechanisms in yeast will be useful in extrapolating related pathways in higher organisms, and may assist in the generation of new tools for genetic engineering, as well in the design of new anti-microbials.