Aberrant transcription and post-transcriptional processing of hepatitis C virus non-structural genes in transgenic mice

• Published in: Transgenic research Vol. 20; no. 6; pp. 1273 - 1284
• Main Authors: Desai, Mayura M, Tumurbataar, Batbayar, Zhang, Yueqing, Chan, Lee-Nien Lillian, Sun, Jiaren, Chan, Teh-sheng
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer-Verlag 01.12.2011; Springer Netherlands; Springer; Springer Nature B.V
• Subjects: Animal Genetics and Genomics; Animal models; Animals; Base Sequence; Biological and medical sciences; Biomedical and Life Sciences; Biomedical Engineering/Biotechnology; Biotechnology; Blotting, Northern; Cell Line; Cell Nucleus; Cell Nucleus - genetics; Cell Nucleus - metabolism; Chronic infection; Codon, Terminator; Codon, Terminator - genetics; Codon, Terminator - metabolism; complementary DNA; Female; Frameshifting, Ribosomal; Fundamental and applied biological sciences. Psychology; gene expression; Gene Expression Regulation, Viral; Genetic Engineering; Genetic technics; genetics; Hepacivirus; Hepacivirus - genetics; Hepacivirus - pathogenicity; Hepatitis C virus; Humans; Language; Life Sciences; liver; Liver - metabolism; Liver - virology; Liver diseases; Male; metabolism; Methods. Procedures. Technologies; Mice; Mice, Inbred C57BL; Mice, Transgenic; Molecular Medicine; Molecular Sequence Data; Northern blotting; Nuclei; Original Paper; pathogenicity; Plant Genetics and Genomics; Plasmids; Plasmids - genetics; Plasmids - metabolism; polyproteins; Post-transcription; proteins; rapid amplification of cDNA ends; Reading Frames; Recombination; RNA; RNA processing; RNA Processing, Post-Transcriptional; RNA, Messenger; RNA, Messenger - genetics; RNA, Messenger - metabolism; Stop codon; trans-splicing; Transcription; transcription (genetics); Transcription initiation; Transcription Initiation Site; Transcription, Genetic; Transgenes; Transgenic animals and transgenic plants; Transgenic mice; Transgenics; Translation; translation (genetics); Viral Nonstructural Proteins; Viral Nonstructural Proteins - genetics; Viral Nonstructural Proteins - metabolism; virology; Transgenic mouse; Hepatitis C virus; Non-structural proteins; Trans-splicing; Aberrant transcription; Splicing; Transcription; Rodentia; Transgenic animal; Protein; Virus; Vertebrata; Mammalia; Gene; Mouse; Flaviviridae; Hepacivirus
• ISSN: 0962-8819; 1573-9368; 1573-9368
• DOI: 10.1007/s11248-011-9494-x

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.