Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, 31037, Toulouse, France.
Université Toulouse III Paul Sabatier, 31330, Toulouse, France.
Nat Commun. 2020 May 27;11(1):2661. doi: 10.1038/s41467-020-16168-x.
RNA G-quadruplexes (RG4s) are four-stranded structures known to control mRNA translation of cancer relevant genes. RG4 formation is pervasive in vitro but not in cellulo, indicating the existence of poorly characterized molecular machinery that remodels RG4s and maintains them unfolded. Here, we performed a quantitative proteomic screen to identify cytosolic proteins that interact with a canonical RG4 in its folded and unfolded conformation. Our results identified hnRNP H/F as important components of the cytoplasmic machinery modulating the structural integrity of RG4s, revealed their function in RG4-mediated translation and uncovered the underlying molecular mechanism impacting the cellular stress response linked to the outcome of glioblastoma.
RNA 四链体(RG4s)是一种已知能够控制癌症相关基因 mRNA 翻译的四链结构。RG4 的体外形成是普遍存在的,但在细胞内却不存在,这表明存在一种特征不明显的分子机制,可以重塑 RG4 并使其保持展开状态。在这里,我们进行了定量蛋白质组学筛选,以鉴定与折叠和展开构象中的典型 RG4 相互作用的胞质蛋白。我们的结果确定了 hnRNP H/F 是调节 RG4 结构完整性的胞质机制的重要组成部分,揭示了它们在 RG4 介导的翻译中的功能,并发现了影响与胶质母细胞瘤结果相关的细胞应激反应的潜在分子机制。