Trans-splicing of RNA in Endometrail Stroma and Other Tissues

描述(申请人提供)：本申请中提出的研究是基于申请人实验室的最新发现，即人子宫内膜间质肿瘤中的JAZF1-JJAZ1基因融合与正常子宫内膜间质细胞中这两个基因的前mRNAs反式剪接的结果相似。更多的证据表明，在正常子宫内膜中，前mRNAs之间的反式剪接受到生理调节，但在肿瘤中，基因融合以一种异常、失调的方式产生嵌合RNA。这些数据导致了一种假设，即其他肿瘤中的基因融合可能以类似的方式促进这些肿瘤的肿瘤表型，途径是在细胞和组织发育的特定时间段持续表达通常由反式剪接产生的嵌合RNA。初步发现和上述假设将通过五个具体目标来进行。前两个目标(确定JAZF1和JJAZ1前-mRNAs在反式剪接过程中的核内定位，以及确定一个对反式剪接来说应该是唯一的RNA Y型中间体)将通过研究这一过程的机制特征，为反式剪接提供进一步的证据。这些目标还将提供研究程序，将有助于研究其他反式剪接的例子。第三个目标(分析JAZF1和PHF1前-mRNAs之间的反式剪接)将调查第二个可能的肿瘤基因融合模仿子宫内膜间质细胞的反式剪接。第四个目标(分析子宫内膜间质细胞中嵌合RNA的功能)将解决反式剪接在正常子宫内膜间质中的作用，第五个目标(展示非子宫内膜间质细胞中的反式剪接)将确定与某些人类肿瘤相关的几个选定基因融合是否反映了这些肿瘤的正常组织中的反式剪接。总之，这项申请中提出的研究将拓宽关于正常组织中RNA反式剪接的知识，并为一类重要的DNA重排如何在人类肿瘤中发挥致癌作用提供新的见解。

DESCRIPTION (provided by applicant): The research proposed in this application is based on the recent discovery in the applicant's laboratory that a JAZF1-JJAZ1 gene fusion in human endometrial stromal tumors mimics the results of trans-splicing between pre-mRNAs for these two genes in normal endometrial stromal cells. Additional evidence suggests that in the normal endometrium trans-splicing between the pre- mRNAs is physiologically regulated, but in the tumors the gene fusion produces chimeric RNA in an abnormal, dysregulated manner. These data have led to the hypothesis that fusions of genes in other tumors may contribute to the neoplastic phenotype of those tumors in a similar fashion, through the sustained expression of chimeric RNAs normally generated by trans-splicing during specific intervals in cell and tissue development. The preliminary findings and the above hypothesis will be pursued through five specific aims. The first two of these aims (determination of the intranuclear localization of JAZF1 and JJAZ1 pre-mRNAs during the trans-splicing process and identification of an RNA Y-form intermediate that should be unique for trans-splicing) will add further proof for trans-splicing by addressing features of the mechanism for this process. These aims will also provide research procedures that will be useful in studying other examples of trans-splicing. The third aim (analysis of trans-splicing between JAZF1 and PHF1 pre-mRNAs) will investigate a likely second case of a neoplastic gene fusion mimicking trans-splicing in endometrial stromal cells. The fourth aim (analysis of chimeric RNA function in endometrial stromal cells) will address the role of trans-splicing in normal endometrial stroma, and the fifth aim (demonstration of trans-splicing in cells other those of endometrial stroma) will determine whether several, selected gene fusions associated with certain human tumors reflect trans-splicing in the normal tissue counterparts of those tumors. In aggregate, the research proposed in this application will broaden knowledge of RNA trans-splicing in normal tissues and provide new insights into how an important class of DNA rearrangements exerts oncogenic effects in human tumors.