在花草马赛克病毒中进行后转录转激活
J M Bonneville1, H Sanfaçon, J Fütterer
1Friedrich Miescher-Institut, Basel, Switzerland.
Cell
|December 22, 1989
概括
植物细胞可以从花草马赛克病毒中翻译dcistronicmRNA. 病毒ORF VI的转激活增强了这些病毒mRNA的下游基因表达.
科学领域:
- 植物分子生物学 植物分子生物学
- 病毒学 病毒学
- 基因表达 基因表达
背景情况:
- 花草马赛克病毒 (CaMV) 产生多基RNA,挑战标准的翻译机制.
- 了解植物细胞如何处理病毒多基斯特龙mRNA对于病毒基因表达研究至关重要.
研究的目的:
- 为了研究植物细胞中二基斯特龙mRNAs的翻译.
- 确定白菜花马赛克病毒 (CaMV) 基因VI在调节多基斯特龙mRNA下游基因表达中的作用.
主要方法:
- 通过融合氨基醇乙转移酶 (CAT) 和β-葡萄糖化酶 (GUS) 记者基因构建二基斯特龙mRNA,将其融合到CaMV ORF I.
- 用记者等离子体和CaMVDNA感染植物原生体.
- 在转激活基因 (ORF VI) 上进行删除分析.
主要成果:
- 报告者基因表达仅在与病毒DNA共传染时显著增强,这表明了转激活机制.
- 转激活特别促进了下游记者基因的表达,而不会影响上游ORF表达.
- 主要的记者转录仍然是双的,在转激活时,丰度的变化有限.
结论:
- CaMV ORF VI通过转激活下游开放阅读框架 (ORF) 在多基斯特龙mRNA上的翻译.
- 这种转激活机制提高了病毒RNA背景下下游基因表达的效率.
- 这些发现揭示了植物病毒使用的复杂的转录后调节策略.
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