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阿尔戈纳特2的核定位受细胞密度的影响,并可能缓解微RNAs的抑制
Krystal C Johnson1, Audrius Kilikevicius1, Cristina Hofman1
1UT Southwestern Medical Center, Departments of Pharmacology and Biochemistry, Dallas, TX 75235, USA.
Nucleic acids research
|December 18, 2023
概括
在特定条件下,阿尔戈诺特蛋白2 (AGO2) 转移到细胞核,去抑制基因标并增加细胞迁移. 这种局部化受到微RNA (miRNA) 处理和辅因子的影响,影响基因调节.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 遗传学 是一个
背景情况:
- 阿尔戈纳特蛋白通过miRNA诱导的沉默复合体 (miRISC) 调解转录后基因沉默.
- 主要是细胞质的AGO蛋白的定位对于miRNA功能至关重要,但在某些条件下可以发生核积累.
- 核AGO积累的功能后果在很大程度上仍未定义.
研究的目的:
- 研究阿尔戈诺特蛋白2 (AGO2) 核定位的条件和后果.
- 确定环境因素和RNA干扰 (RNAi) 机制组件如何影响AGO2局部化和下游基因表达.
- 阐明AGO2核进口在细胞迁移等过程中的作用.
主要方法:
- 在2D和3D培养模型中利用了HCT116细胞,以及人类结肠瘤样本来评估AGO2局部化.
- 采用eCLIP (增强交联免疫沉) 来识别AGO2结合的RNA.
- 通过工程核定位信号生成具有构成性核AGO2定位的细胞.
- 对关键RNAi因子DROSHA和TNRC6进行基因淘汰,以研究它们对AGO2定位的影响.
主要成果:
- 在高密度2D培养物,3D瘤球体和人类结肠瘤中观察到AGO2的核丰富.
- 核AGO2去压缩的细胞质标通常由miRISC调节.
- 构成性核AGO2表达增强了细胞迁移.
- DROSHA的耗尽导致了细胞质AGO2的局部化,而TNRC6的耗尽导致了核AGO2的局部化.
结论:
- AGO2局部化是动态的,对细胞环境,miRNA生物发生和miRISC辅因子表达有反应.
- 核AGO2在抑制基因表达和促进细胞迁移方面发挥作用.
- 考虑AGO2局部化和miRISC组件的表达对于理解miRNA介导的基因调节至关重要.
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