Aberrant transcription and post-transcriptional processing of hepatitis C virus non-structural genes in transgenic mice.
Aberrant transcription and post-transcriptional processing of hepatitis C virus non-structural genes in transgenic mice.
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转基因小鼠丙型肝炎病毒非结构基因的异常转录和转录后加工。
DOI：
10.1007/s11248-011-9494-x
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发表时间：
2011
影响因子：
3
通讯作者：
Chan,Teh-Sheng
中科院分区：
文献类型：
--
作者：
Desai,MayuraM;Tumurbataar,Batbayar;Zhang,Yueqing;Chan,Lee-NienLillian;Sun,Jiaren;Chan,Teh-Sheng
丙型肝炎病毒（HCV）感染是世界范围内慢性肝病的主要原因。由于感染的几个方面尚未解决，迫切需要一种方便的动物模型，可以模拟临床疾病，并帮助评估治疗策略。尽管在用于开发HCV啮齿动物模型的转基因方法中已经取得了一些成功，但是完整HCV多蛋白或整套病毒非结构（NS）蛋白的转基因表达仍然是一个严峻的挑战。利用北方杂交和5′端快速扩增cDNA末端（RACE）技术，我们揭示了两种可能的机制，可以阻止HCV NS转基因在小鼠肝脏中的表达。在鼠体内环境中，几种截短的转录物从沿着沿着HCV NS序列的交替转录起始位点产生。这些较短的转录本的翻译被上下文终止密码子的定位或通过阅读框的移位阻断。此外，完整的NS转录物通过与非转基因衍生的剪接前导序列的5′重组进行反式剪接，该剪接前导序列在翻译起始点上游附加潜在的终止密码子。因此，这些发现表明，HCV NS衍生的转基因在小鼠宿主的细胞核中受到异常的转录起始和转录后加工。防止这种异常转录起始/RNA加工的策略可能是开发成功的HCV转基因小鼠模型的关键。
Hepatitis C virus (HCV) infection is a leading cause of chronic liver disease worldwide. Since several aspects of the infection remain unresolved, there is a pressing need for a convenient animal model that can mimic the clinical disease and aid the evaluation of treatment strategies. Although some success has been achieved in transgenic approaches for development of rodent models of HCV, transgenic expression of the complete HCV polyprotein or an entire set of the viral non-structural (NS) proteins continues to be a serious challenge. Using northern blot and 5′ rapid amplification of cDNA ends (RACE), we unraveled two possible mechanisms that can impede HCV NS transgene expression in the mouse liver. Several truncated transcripts are produced from alternate transcription start sites along the HCV NS sequence within the murine environment, in vivo. Translation of these shorter transcripts is blocked either by the positioning of a contextual stop codon or through a shift in the reading frame. In addition, the complete NS transcript undergoes trans-splicing through 5′ recombination with a non-transgene-derived, spliced leader sequence that appends a potential stop codon upstream of the translation start. These findings thus demonstrate that HCV NS-derived transgenes are subject to aberrant transcriptional initiation and post-transcriptional processing in the nucleus of a mouse host. Strategies to prevent such aberrant transcription start/RNA processing might be key to the development of a successful HCV transgenic mouse model.