Characterizing functional targets of a non-coding RNA oncogene, SNORA42

描述（由申请人提供）：snoRNA是指导其靶RNA的位点特异性转录后RNA修饰（假尿苷化或2 ′-O-甲基化）的非编码向导RNA。虽然snoRNA的生物化学功能相对较好地表征，但它们的生物学作用才刚刚开始探索。值得注意的是，特定snoRNA的失调与乳腺癌、前列腺癌、肺癌、脑癌和结肠直肠癌以及白血病和多发性骨髓瘤的风险增加有关。最值得注意的是，一个假尿苷化指导snoRNA，SNORA 42，最近被确定为非小细胞肺癌（NSCLC）的癌基因。尽管人们越来越认识到snoRNA生物学的医学意义，但改变snoRNA活性导致癌症的机制仍然是个谜。我们有初步的数据支持snoRNA功能的一个新的范例，我们在这里建议在增加NSCLC细胞增殖和转移的背景下进行研究。使用一种新的技术（伪seq），使我们能够以单核苷酸分辨率在全基因组范围内绘制假尿苷（φ）的位置，我们首次证明了内源性人类信使RNA（mRNAs）在特定位点含有φ。由于以前已知的snoRNA靶点仅限于核糖体RNA，或较少的剪接体小RNA，因此这一突破将SNORA 42的潜在癌症相关靶点的数量扩大了100倍以上，并提高了致癌SNORA 42的扩增/过表达通过干扰mRNA靶点的修饰而导致肿瘤发生的可能性。虽然内源性mRNA假尿苷化的分子结果仍有待确定，但最近的工作戏剧性地说明了这种转录后mRNA修饰的潜在意义：将φ s人工掺入模型mRNA中改变了遗传密码的含义！基于这些发现，我们建议进行一项探索性研究计划：（1）研究非小细胞肺癌中位点特异性mRNA假尿苷化的分子和细胞效应;（2）全面鉴定snoRNA癌基因SNORA 42的假尿苷化靶点。总之，拟议的研究将阐明SNORA 42的过度表达/基因组扩增导致肺癌预后不良的机制。

DESCRIPTION (provided by applicant): snoRNAs are non-coding guide RNAs that direct site-specific post-transcriptional RNA modifications - either pseudouridylation or 2'-O-methylation - of their target RNAs. Although snoRNAs' biochemical functions are relatively well characterized, their biological roles are just beginning to be explored. Notably, dysregulation of specific snoRNAs is associated with increased risk for breast, prostate, lung, brain and colorectal cancers as well as leukemia and multiple myeloma. Most remarkably, one pseudouridylation-directing snoRNA, SNORA42, was recently identified as an oncogene in non-small cell lung carcinoma (NSCLC). Despite increasing awareness of the medical significance of snoRNA biology, the mechanisms by which altered snoRNA activities cause cancer remain mysterious. We have preliminary data supporting a new paradigm for snoRNA function, which we here propose to investigate in the context of increased NSCLC cell proliferation and metastasis. Using a novel technology (Pseudo-seq) that allows us to map the locations of pseudouridines (φ) genome-wide with single nucleotide resolution, we have demonstrated for the first time that endogenous human messenger RNAs (mRNAs) contain φ's at specific sites. Because previously known snoRNA targets were restricted to ribosomal RNAs, or less frequently, spliceosomal small RNAs, this breakthrough expands the number of potential cancer-relevant targets of SNORA42 more than 100-fold, and raises the possibility that amplification/over-expression of oncogenic SNORA42 causes tumorigenesis by perturbing modification of mRNA targets. Although the molecular consequences of endogenous mRNA pseudouridylation remain to be determined, recent work dramatically illustrates the potential significance of this post-transcriptional mRNA modification: artificial incorporation of φ's into model mRNAs changes the meaning of the genetic code! Building on these discoveries, we propose to conduct an exploratory research program (1) to investigate the molecular and cellular effects of site-specific mRNA pseudouridylation in non-small cell lung carcinoma; and (2) to comprehensively identify the pseudouridylated targets of the snoRNA oncogene SNORA42. Together, the proposed investigations will illuminate the mechanisms by which over-expression/genomic amplification of SNORA42 contributes to lung cancer with poor prognosis.