Investigating the function of novel cis-regulatory elements in 3'UTRs of mRNAs and their molecular mechanisms in post-transcriptional gene regulation.

多种转录后调控机制对基因表达有重要影响，并最终改变合成蛋白质的数量。转录后调控是由顺式调节元件和反式作用因子介导的，顺式调节元件通常位于mRNAs的非翻译区(UTRs)，反式作用因子与这些元件结合。一项全基因组范围的比较研究表明，在3个UTRs中存在数百个新的潜在顺式调控元件。虽然已经阐明了几种转录后调控机制，但这些元件的流行假设还有许多额外的途径有待发现。本项目旨在识别和分析新的转录后基因调控元件的潜在分子机制。首先，它们的作用模式将通过遗传和生化分析来检查，以确定它们是否调节mRNA的成熟、输出到细胞质、亚细胞定位、稳定性和/或翻译。其次，新的顺式元件调控所需的反式作用因子，可能是蛋白质，将通过候选基因方法和基于全基因组RNAi的筛选来识别。由于我们打算研究的顺式调控元件存在于许多不同的mRNAs中，其机制和反式作用因子的发现有望对基因表达的调控具有广泛的意义。

A variety of post-transcriptional regulatory mechanisms significantly contribute to gene expression and ultimately alter the amount of synthesized protein. Post-transcriptional regulation is mediated by cis-regulatory elements, typically located within the untranslated regions (UTRs) of mRNAs, and trans-acting factors that bind to these elements. A genome-wide comparative study indicates the existence of hundreds of novel potential cis-regulatory elements within 3¿UTRs. Although several post-transcriptional regulatory mechanisms have been elucidated, the prevalence of these elements supposes many additional pathways to be discovered. This project aims to identify and analyze the underlying molecular mechanisms of novel post-transcriptional gene regulatory elements. First, their mode of action will be examined by genetic and biochemical assays, to determine if they regulate mRNA maturation, export into the cytoplasm, sub-cellular localization, stability and/or translation. Second, the trans-acting factors, presumably proteins, required for novel cis-element regulation, will be identified by using both a candidate gene approach and whole-genome RNAi-based screening. Since the cis-regulatory elements, we propose to study, are present in many different mRNAs, the discoveries of their mechanisms and trans-acting factors are expected to have broad significance to the regulation of gene expression.