人类DICER1热点突变导致miRNA功能损失和增加
David Jee1, Seungjae Lee1, Dapeng Yang1
1Developmental Biology Program, Sloan Kettering Institute, New York, NY, USA.
Nature structural & molecular biology
|November 4, 2025
概括
癌症中的DICER1突变破坏了微RNA (miRNA) 处理. 一项新的研究显示,这些突变导致链切换,有利于miRNA-3p加载并增加基因抑制.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 癌症生物学 癌症生物学
背景情况:
- 酶DICER1对于微RNA (miRNA) 生物生成至关重要,它将前体miRNA加工成成熟的链.
- 癌症中经常出现的DICER1突变通常会影响其RNase IIIb域,损害其功能.
- 由于缺乏适当的模型,对这些突变的精确分子后果的理解受到限制.
研究的目的:
- 通过使用人类胚胎干细胞模型,研究DICER1突变对miRNA生物发生和功能的功能影响.
- 阐明DICER1突变改变miRNA链选择和基因抑制的分子机制.
主要方法:
- 产生DICER1-knockout和DICER1(S1344L) 突变的人类胚胎干细胞 (同卵性和半卵性).
- 使用RNA测序对miRNA资料的分析.
- 在体外测定以评估前-miRNA处理和阿尔戈诺特加载.
- 对基因抑制能力的评估.
主要成果:
- DICER1淘汰赛细胞缺乏正规的miRNAs.
- DICER1 ((S1344L) 突变导致miRNA-5p链的切除和miRNA-3p链的选择性变化.
- 观察到miRNA-3p乘客链的方向上调,表明链切换.
- 3p-arm-nicked预miRNAs优先加载miRNA-3p物种到Argonaute中,增强基因抑制能力.
结论:
- 癌症中的DICER1热点突变诱导了miRNA生物发生中的显著链切换,有利于miRNA-3p链的加载.
- 这种改变的miRNA负载增强了DICER1突变细胞的基因抑制能力.
- 这些发现扩大了对DICER1突变在癌症中的分子后果的理解.
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