艾滋病毒-1 Nefs 是载荷敏感的AP-1 三分化开关
Kyle L Morris1, Cosmo Z Buffalo1, Christina M Stürzel2
1Department of Molecular and Cell Biology and California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA.
Cell
|July 28, 2018
概括
艾滋病毒Nef蛋白破坏细胞通路以逃避免疫反应. 它与AP-1和Arf1蛋白质的相互作用通过控制细胞内的蛋白质分类来决定病毒逃避.
科学领域:
- 结构生物学
- 病毒学
- 细胞生物学
背景情况:
- 艾滋病毒辅助蛋白Nef对于病毒病变至关重要.
- 通过操纵细胞运输途径,特别是涂层囊泡运输,Nef对宿主免疫防御进行了抵制.
- 了解Nef的机制是开发抗病毒策略的关键.
研究的目的:
- 阐明HIV Nef蛋白与AP-1克拉特林适配体和Arf1GTPase相互作用的结构机制.
- 确定这些相互作用如何导致细胞贩运途径的颠覆和免疫规避.
- 研究Nef酸化在调节这些过程中的作用.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定蛋白质复合物的高分辨率结构.
- 交换质谱 (HDX-MS) 用于分析蛋白质动态.
- 突变分析以探测功能相互作用.
- 生物化学测试以评估蛋白质复合体的形成和功能.
主要成果:
- 确定了与Arf1,HIV-1 Nef复合的封闭AP-1三元体的冷-EM结构,并揭示了通过戈尔吉保留来激活tetherin的机制.
- 阐明了Nef诱导的AP-1二元体的结构,突出了Nef的dieleucine循环在调节AP-1三元化中的作用.
- HDX-MS和突变研究表明,载荷动态影响Arf1的三分化,指导Nef目标进行跨戈尔吉保留或溶酶分类.
- 鉴定了NL4-3M-Nef的酸化作为AP-1三元化的一个关键调节剂,解释了Nef变异的差异性素对抗作用.
结论:
- 艾滋病毒Nef蛋白可以调节像AP-1这样的膀层的高阶组织.
- 这种调节将病毒载荷引导到特定的细胞命运,促进免疫逃逸.
- 尼夫与AP-1和Arf1的相互作用为抗病毒疗法提供了新的点.
相关概念视频
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