由爱斯坦-巴尔病毒编码的EBNA1自抑制合成和抗原呈现
Yili Yin1, Bénédicte Manoury, Robin Fåhraeus
1Division of Molecular Physiology, Faculty of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
Science (New York, N.Y.)
|September 6, 2003
概括
爱斯坦-巴尔病毒核抗原1 (EBNA1) 的甘氨酸-氨酸重复域 (GAr) 抑制了其自身的mRNA翻译,而不仅仅是蛋白质降解. 这种翻译抑制是通过隐藏EBNA1表位体来防止细胞毒性T细胞识别的关键.
科学领域:
- 病毒学 病毒学
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
背景情况:
- 爱斯坦-巴尔病毒核抗原1 (EBNA1) 逃避细胞毒性T细胞检测.
- 据认为,EBNA1的甘氨酸-氨酸重复域 (GAr) 仅通过抑制蛋白质体降解来防止抗原呈现.
研究的目的:
- 研究EBNA1的GAr域阻止MHC I类受限制抗原呈现的机制.
- 为了确定mRNA翻译抑制是否有助于EBNA1免疫逃避.
主要方法:
- 进行了体外和体内实验.
- 测试用于区分对蛋白质体降解和mRNA翻译的影响.
主要成果:
- 在cis中,GAR域抑制EBNA1mRNA转化.
- 这种翻译抑制与其对蛋白质体降解的影响是可分离的.
- 抑制mRNA翻译,而不是蛋白质降解,对于防止MHC I类分子上抗原呈现至关重要.
结论:
- EBNA1利用mRNA翻译抑制作为逃避细胞毒性T细胞识别的主要机制.
- 尽量减少EBNA1转录翻译可以防止免疫检测,同时通过阻断降解保持足够的蛋白质水平.
相关概念视频
00:42Cross-reactivity
Overview
02:28Leaky Scanning
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R stands for...
01:30Inhibitors of Viral Protein Synthesis
Protein synthesis is indispensable for viral replication, as viruses lack the cellular machinery required for this process and must hijack the host's translational apparatus. In response, host cells deploy a critical innate immune defense involving interferons, specialized cytokines that play a central role in inhibiting viral propagation.Upon viral detection, infected cells release interferons that bind to receptors on adjacent uninfected cells, activating the JAK-STAT signaling pathway and...