Mechanism of Regulation of mRNA Stability

描述（由申请人提供）：我们的目标是阐明参与一般和调节mRNA稳定性的途径和机制，这是一个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的过程。我们实现这一目标的方法将主要集中在一个新的体外系统，我们已经开发并成功地利用在过去，忠实地再现方面的一般和调节mRNA的稳定性外源RNA底物。首先，通过将结构块策略性地放置到RNA底物中，我们将确定在去腺苷化后mRNA体的降解中所涉及的体内途径。其次，我们将使用体外方法来确定如何去腺苷化的mRNA底物的差异调节不同类AU丰富的元素。第三，我们将确定非AU丰富的元素，即重要的免疫调节剂CD 154的嘧啶丰富的元素和c-jun原癌基因的U丰富的元素，如何发挥作用，以调节mRNA的稳定性。最后，我们最近鉴定了3种蛋白质的复合物，其以聚腺苷酸化依赖的方式组装在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稳定性的机制和调节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，并提供对疾病（例如癌症）的分子基础的见解和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.