基因重叠导致一种具有RNA结合域和主要外套蛋白质域的病毒蛋白
1Section on Genetics of Simple Eukaryotes, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892.
Cell
|November 18, 1988
概括
研究人员发现,酵母病毒样粒子 (VLPs) 中的一种特定蛋白质与单链RNA (ssRNA) 结合,对于复制双链RNA (dsRNA) 是必不可少的. 这种蛋白质是由L-A dsRNA基因组编码的.
科学领域:
- 分子病毒学分子病毒学
- 酵母遗传学 酵母遗传学
- 复制RNA复制RNA的复制
背景情况:
- 通过一种保守的异步过程,L-A双链RNA (dsRNA) 在酵母病毒样颗粒 (VLPs) 中复制.
- 通过包装新合成 (+) 链来组装新的病毒颗粒.
研究的目的:
- 研究酵母中L-A dsRNA复制和粒子形成的机制.
- 为了确定宿主因素和病毒蛋白质参与RNA结合和复制在VLP.
主要方法:
- 病毒 (+) 单链RNA (ssRNA) 在体外转化为dSRNA,使用孤立的VLP和宿主因子.
- 使用西方斑点对VLP蛋白质ssRNA结合活性进行分析.
- 180kDa蛋白与主要外套蛋白和L-A (+) 链序列的免疫学比较.
主要成果:
- 空的VLP特异地与病毒 (+) ssRNA结合,这种与宿主因子的结合导致dSRNA在体外合成.
- 孤立的结合复合物只能在宿主因子存在时形成复制.
- 小VLP180 kDa蛋白具有ssRNA结合活性,并与主要外套蛋白和L-A (+) 链共享抗原域,表明它也被L-A dsRNA编码.
结论:
- L-A dsRNA基因组编码了一个180 kDa的蛋白质,它既具有主要外套蛋白质域,也具有ssRNA结合域.
- 这种180kDa的蛋白质对于酵母VLP中的ssRNA的特定结合和随后的dsRNA复制至关重要,需要宿主因子.
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