反复发生的非编码U1snRNA突变导致SHH骨髓母细胞瘤的神秘拼接
Hiromichi Suzuki1,2, Sachin A Kumar1,2,3, Shimin Shuai4,5
1The Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada.
Nature
|October 31, 2019
概括
高度重复的U1结合体小核RNA (snRNA) 突变驱动Sonic刺细胞瘤. 这些非编码RNA突变会破坏结合,影响瘤基因和瘤抑制剂,从而成为潜在的治疗点.
科学领域:
- 癌症学
- 遗传学
- 分子生物学
背景情况:
- 在儿童癌症中,反复发生的体变异通常是罕见的,主要影响蛋白质编码基因.
- U1 spliceosomal小核RNAs (snRNAs) 是spliceosome的关键组成部分,参与RNA拼接.
研究的目的:
- 研究非编码基因,特别是U1 snRNAs的突变在儿童癌症中的作用.
- 在特定的骨髓母细胞瘤亚群中识别U1 snRNAs的复发性突变.
主要方法:
- 整个外细胞组测序和细胞核细胞样本的变异分析.
- 测序RNA以评估拼接模式并识别神秘的拼接事件.
- 对不同癌症类型和患者人口统计数据的突变频率的分析.
主要成果:
- 在约50%的Sonic hedgehog (SHH) 脑髓母细胞瘤中发现U1 snRNA中高度复发的热点突变 (r.3A>G).
- 这些U1 snRNA突变在97%的成人和25%的青少年中发现,但很少在婴儿或其他癌症类型中发现 (< 0. 1%).
- 在U1 snRNA中发生的突变导致RNA拼接中断,5'密码拼接增加,瘤抑制剂 (PTCH1) 失活,瘤基因激活 (GLI2,CCND2).
结论:
- U1 snRNA 突变代表癌症中非编码基因中高度复发的组织特异性突变的一类新奇突变.
- 这些突变通过异常拼接显著改变基因表达,推动SHH髓母细胞瘤的发展.
- 针对突变U1 snRNA介导的替代拼接是一种潜在的SHH髓母细胞瘤治疗策略.
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