Regulation of mRNA fate

摘要 选择性剪接（AS）过程是从细胞中产生mRNA多样性的强大机制。 蛋白质编码基因来自同一基因的替代mRNA同种型可以彼此细微不同， 在它们的序列组成上有根本的改变。值得注意的是，我们对 这种多样的mRNA库被转化为蛋白质。解决这个问题的一个有趣的线索来自我们的 最近的研究表明，选择性剪接的过程会影响蛋白质的翻译效率， 产生的mRNA同种型。在这个建议中，我们使用生物化学和分子方法来解开 复杂的机制耦合转录后基因表达。通过确定AS-TC元素如何调节， 我们将能够反驳或支持这一建议的中心假设，即交替的mRNA翻译， 可变剪接的转录物被包装成功能不同的信使核糖核蛋白颗粒 （mRNP）。如果与差异多聚核糖体结合相关的序列不直接控制翻译 起始或延伸，那么我们将考虑我们的替代假设：mRNA的显著部分异源化， 形式多样性来自于噪声剪接，然后被一些未知的mRNA从多聚核糖体中排除 监视路径。解决这一重要问题不仅将揭示顺式元件如何影响反式元件， 但也将定义选择性剪接和mRNA的过程之间的机械联系 翻译.从长远来看，我们的研究计划将为基于RNA的诊断提供新的机会。 以及适用于多种人类疾病的治疗方法。

Abstract The process of alternative splicing (AS) is a powerful mechanism for generating mRNA diversity from protein coding genes. Alternative mRNA isoforms from the same gene can differ subtly from each other or have radical alterations in their sequence composition. Remarkably, very little is known about whether or not this diverse pool of mRNA is converted to protein. One intriguing clue for solving this problem comes from our recent studies suggesting that the process of alternative splicing influences the translational efficiency of the resultant mRNA isoforms. In this proposal, we use both biochemical and molecular approaches to untangle the intricate mechanisms coupling post-transcriptional gene expression. By determining how AS-TC elements reg- ulate mRNA translation we will be able to refute or support the central hypothesis of this proposal, that alterna- tively spliced transcripts are packaged into functionally distinct messenger ribonucleoprotein particles (mRNPs). If sequences associated with differential polyribosome association do not directly control translation initiation or elongation, then we will consider our alternative hypothesis: that a significant fraction of mRNA iso- form diversity arises from noisy splicing which are then excluded from polyribosomes by some unknown mRNA surveillance pathway. Solving this important problem will not only reveal how cis-elements influence transla- tional yield, but will also define mechanistic links between the processes of alternative splicing and mRNA translation. In the long-term, our research program will facilitate new opportunities for RNA-based diagnostics and therapies that will be applicable to a wide array of human diseases.