RNA localization and tumor suppression by APC

描述(申请人提供)：肿瘤抑制蛋白APC的缺失是结直肠癌的主要原因。APC在调节转录因子β-连环蛋白方面具有众所周知的作用。然而，APC的其他独立于β-连环蛋白的功能也有助于肿瘤的发生。这些功能可能与在间期突起和有丝分裂纺锤体的微管末端的簇中发现的APC亚群有关。我最近发现，在突出处的APC集群在定位一大组RNA方面具有意想不到的作用。在我提出的研究中，我将确定这种新的APC角色是否也发生在有丝分裂纺锤体上。我将确定在有丝分裂过程中与APC相关的RNA，并确定APC-RNA相互作用在细胞周期中是如何调节的。此外，我还将设计一种新的基于FRET的分析方法来成像体内的RNA翻译，以确定这些局部RNA的功能是否与它们的翻译有关，或者它们是否具有其他结构角色。我将进一步讨论致癌APC突变如何影响RNA定位，我将剖析APC-RNA复合体的分子组成，以便具体干扰它们的定位，并确定它们在APC突变诱导的肿瘤发生中的作用。为了成功地进行这些研究，在指导阶段，我将接受FRET方法的培训，并可以使用最先进的成像设备来开发基于FRET的翻译记者。我还将通过课程和研讨会进行癌症生物学方面的培训。这次培训将使我能够扩大我的专业知识，目标是建立一个独立的研究小组，研究RNA定位在癌症中的参与，范围从基本的分子机制到动物模型的功能分析。弗吉尼亚大学激动人心的研究环境和现有设施为拟议的培训提供了最佳场所。具体地说，马卡拉博士的实验室在各种模型系统中研究细胞极性机制及其与癌症进展的关系方面拥有丰富的专业知识，因此非常适合帮助我实现我的目标。 相关性：结直肠癌是癌症患者的第二大死因，其原因是肿瘤抑制蛋白APC的缺失。然而，尽管APC很重要，但它的分子功能还没有完全被理解。这项工作将探索一个新的APC角色及其与肿瘤进展的联系，从而可能为预防或治疗结直肠癌提供有价值的信息。

DESCRIPTION (provided by applicant): Loss of the tumor suppressor protein APC is the main cause of colorectal cancer. APC has a well-known role in regulating the transcription factor beta-catenin. However, other functions of APC, independent of beta-catenin, also contribute to tumorigenesis. These functions are likely linked to a subpopulation of APC found in clusters at the distal tips of microtubules both in interphase protrusions and on the mitotic spindle. I recently discovered that APC clusters at protrusions have an unanticipated role in localizing there a large group of RNAs. During my proposed research, I will determine whether this novel APC role also occurs on the mitotic spindle. I will identify RNAs associated with APC during mitosis and determine how APC-RNA interactions are regulated during the cell-cycle. I will additionally devise a new FRET-based assay to image RNA translation in vivo, in order to determine whether the function of these localized RNAs is related to their translation or whether they have other structural roles. I will further address how oncogenic APC mutations affect RNA localization and I will dissect the molecular composition of the APC-RNA complexes in order to specifically disrupt their localization and determine their contribution to tumorigenesis induced upon APC mutation. To successfully carry out these studies, during the mentored phase, I will be trained in FRET methodology and have access to state-of-the-art imaging facilities to develop the FRET-based translation reporter. I will also undertake training in cancer biology through courses and workshops. This training will allow me to expand my expertise with the goal of setting up an independent research group that will study the involvement of RNA localization in cancer, ranging from basic molecular mechanisms to functional analyses in animal models. The stimulating research environment and the available facilities at UVa provide an optimal place for the proposed training. Specifically, Dr. Macara's lab has significant expertise in studying cell polarity mechanisms and their relation to cancer progression in various model systems and is, therefore, uniquely suited to assist me in achieving my goals. RELEVANCE: Colorectal cancer is the second leading cause of death among cancer patients and is caused by loss of the tumor suppressor protein APC. Despite its importance, however, the molecular functions of APC are not fully understood. This work will explore a novel APC role and its connection to tumor progression, and could thus provide valuable information towards prevention or treatment of colorectal cancers.