Mechanism of Regulation of mRNA Stability

描述(申请人提供)：我们的目标是阐明涉及一般和调控的mRNA稳定性的途径和机制，这一过程在控制与细胞生长和分化相关的基因表达方面发挥重要作用。我们实现这一目标的方法将在很大程度上围绕着我们在过去开发并成功开发的一种新的体外系统，该系统忠实地在外源RNA底物上复制一般和调节的mRNA稳定性的方面。首先，通过将结构块战略性地放置到RNA底物中，我们将确定在体内参与去烯化后信使核糖核酸主体降解的途径。其次，我们将使用体外方法来确定不同类别的富含AU的元素对mRNA底物死烯基化的不同调控方式。第三，我们将确定非AU富集素，即重要的免疫调节剂CD154的富嘧啶元素和c-jun原癌基因的富U元素，如何调节mRNA的稳定性。最后，我们最近发现了一个由3种蛋白质组成的复合体，它以多聚腺苷依赖的方式组装在mRNA的3‘UTR上。我们将研究这些蛋白质在各种转录后过程中的身份和功能意义。这些关于mRNA稳定性的机制和调控的研究将对我们理解细胞生长控制的分子机制产生深远的影响，并为疾病(如癌症)的分子基础提供见解，以及可能改进的基因治疗策略。

DESCRIPTION (provided by applicant): Our goal is to elucidate the pathways and mechanisms involved in general and regulated mRNA stability, a process that plays an important role in controlling aspects of gene expression related to cell growth and differentiation. Our approach to this goal will largely center around a novel in vitro system we have developed and successfully exploited in the past that faithfully reproduces aspects of both general and regulated mRNA stability on exogenous RNA substrates. First, by strategic placement of structural blocks into RNA substrates, we will determine the in vivo pathways involved in the degradation of the body of the mRNA following deadenylation. Second, we will use an in vitro approach to determine how deadenylation of mRNA substrates is differentially regulated by distinct classes AU-rich elements. Third, we will determine how non-AU-rich elements, namely the pyrimidine-rich element of the important immune modulator CD154 and the U-rich element of the c-jun proto-oncogene, function to regulate mRNA stability. Finally, we have recently identified a complex of 3 proteins that assembles on the 3' UTR of an mRNA in a polyadenylation dependent manner. We will investigate the identity and functional significance of these proteins in a variety of post-transcriptional processes. These studies on the mechanisms and regulation of mRNA stability will have a profound impact on our appreciation of molecular mechanisms of cellular growth control, as well as providing insights into the molecular basis of disease (e.g. cancer) and possibly improved strategies for gene therapy.