通过腺病毒对IRE1α-XBP1信号的动态调制
1Department of Radiation Oncology and Molecular Radiation Sciences, The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland USA.
bioRxiv : the preprint server for biology
|December 16, 2024
概括
腺病毒5型 (HAdV5) 激活了未折叠蛋白反应 (UPR),但阻断了X盒结合蛋白1 (XBP1s) 的产生. 这种逃避策略与p53降解一起,突显了癌细胞中缺陷的抗病毒防御.
科学领域:
- 细胞应激反应细胞应激反应
- 病毒学 病毒学
- 分子生物学分子生物学
背景情况:
- 病毒感染引发细胞应激反应,包括未折叠蛋白质反应 (UPR),以维持蛋白质平衡.
- 需要内醇的酶类型1 (IRE1α) 和X盒结合蛋白1 (XBP1) 信号轴对UPR激活和免疫功能至关重要.
- 已知腺病毒血清型5 (HAdV5) 与UPR通路相互作用,先前的研究表明,其复制是由IRE1α-XBP1活性支持的.
研究的目的:
- 研究HAdV5感染与IRE1α-XBP1 UPR信号轴之间的复杂相互作用.
- 阐明 HAdV5 操纵 UPR 组件用于其复制的机制.
- 了解瘤抑制剂p53在HAdV5感染期间调节UPR中的作用.
主要方法:
- 使用HAdV5.5的细胞感染模型.
- 对IRE1α激活和XBP1拼接的分析.
- 调查p53在病毒感染期间的UPR调节中的作用.
主要成果:
- HAdV5感染导致IRE1α激活,但矛盾的是,它抑制了活性XBP1s异型的产生.
- 发现瘤抑制剂p53抑制了IRE1α的激活,并且感染后的降解允许IRE1α去抑制.
- HAdV5最终通过抑制XBP1s的产生来克服宿主防御,这表明了复杂的逃避策略.
结论:
- HAdV5采用了一种复杂的机制来控制UPR,涉及对IRE1α和XBP1.1的对立影响.
- 对p53的降解和随后的IRE1α去抑制代表了一种新的,尽管最终被回避的抗病毒反应.
- 这些发现强调了癌细胞中观察到的抗病毒防御的损害,并突出了UPR调制在病毒感染期间确定细胞命运的关键作用.
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