RBM10介导的选择性剪切调控机制及其与疾病之间分子关联的研究

RBM10 encodes a nuclear RNA binding protein (RBP), which has been identified as a component of spliceosome complex, indicating its potential role in splicing regulation. Mutations in RBM10 have been identified to cause an X-linked pleiotropic developmental anomaly syndrome and implicated in Lung adenocarcinoma as well as Intraductal Papillary Mucinous Neoplasm. However, the in vivo RNA binding sites and splicing regulation induced by RBM10 remain unclear. In addition, the molecular link between its potential function in splicing regulation and underlying disease pathogenesis remains unexplored. In our previous study, we characterized in vivo RBM10-RNA interactions and investigated the role of RBM10 in splicing regulation at the global level, based on which we proposed a mechanistic model explaining RBM10 mediated splicing regulation and established RBM10 as an important splicing regulator. Here we would like to further characterize how the RBM10 mutations identified in Lung adenocarcinoma patients would affect its functions, particularly in terms of RNA binding capacities and splicing regulation, and establish a molecular link between its function in splicing regulation and Lung adenocarcinogenesis. Overall, our work on RBM10 mediated alternative splicing regulatory mechanisms and its molecular link with disease would provide a basis for the application of RBM10 and its target genes in cancer diagnosis and treatment. Moreover,the system established in this study could be widely applied in unraveling the regulatory mechanisms of other RBPs.

RBM10编码一个定位在细胞核的RNA结合蛋白，被鉴定为剪切复合体的一个成分，表明其在剪切调控中的潜在作用。RBM10 突变被发现是导致一种X染色体连锁的多项发育异常综合症的原因以及与肺腺癌、导管内乳头状黏液瘤相关。然而，RBM10在RNA上的结合位点及对剪切的影响目前未知；其潜在的剪切调控功能与疾病发生之间的分子关联未被探索。我们前期的实验首次系统研究了RBM10与RNA的相互作用，鉴定了RBM10引起的剪切变化，并提出了RBM10剪切调控的作用模型，证实了RBM10是一个重要剪切调控因子。本研究项目将对肺腺癌中发现的RBM10突变进行功能分析，进一步揭示突变导致的剪切调控的变化，并建立RBM10介导的剪切调控与肺腺癌发生之间的分子关联。这些研究结果将为RBM10及其靶基因作为潜在的癌症诊断、治疗的分子靶标提供理论基础。所建立的体系将能被广泛应用于其他重要的RNA结合蛋白的作用机制研究中。

RNA剪接是基因表达的一个关键步骤，剪接调控在多种生理条件下发挥着重要的功能。剪接异常是导致人类遗传疾病的主要原因之一，与肿瘤发生发展紧密相关。RBM10编码一个RNA结合蛋白及剪接调控因子，其突变导致一种严重的发育异常遗传疾病TARP综合征，在肺腺癌病人中高频率出现。在该项目中，我们系统鉴定了RBM10在细胞内RNA前体上的结合位点及其引起的剪接变化，通过数据整合分析及实验验证，阐明了RBM10介导剪接调控的分子机制。在此基础上，我们建立了一种数据分析及实验方法，揭示了RBM10通过可变剪接偶联的无义介导的mRNA降解途径(Alternative Splicing-Coupled Nonsense-Mediated mRNA Decay, AS-NMD) 负向调控自身及其同源类似物RBM5表达的新分子机制，发现肺腺癌组织中介导RBM10自我调控的外显子剪接位点突变伴随RBM10表达量显著降低。此外，我们对肺腺癌中出现的RBM10突变进行了系统的功能分析，结果表明RBM10突变呈现与肿瘤抑制基因相似的突变谱，且至少部分通过引起靶标基因的剪接异常在肺腺癌中发挥作用。功能学研究表明RBM10能抑制肺腺癌细胞增殖、细胞周期进展，促进凋亡，并抑制裸鼠体内成瘤。这些研究结果为深入研究RBM10的在不同生理病理条件下的功能、理解剪接因子的作用机制、剪接调控网络及剪接异常与疾病的分子关联提供了重要启示，并将促进RBM10及其标靶基因的剪接在相关疾病诊断、治疗中的应用。