NanoLuc reporters synonymously engineered to different GC contents were inserted into SARS-CoV-2, Japanese encephalitis virus and hepatitis C virus. Mismatched transgenes were deleted or accumulated substitutions toward the viral genome composition in some viruses, while intermediate-GC JEV maintained variants more stably. GC matching is a recombinant-virus design factor, not patient or vaccine-effectiveness evidence.
Key findings
- Low-GC SARS-CoV-2 frequently deleted GC-rich Nluc. SARS-CoV-2 and HCV accumulated substitutions, mainly at third codon positions, shifting GC toward the viral genome. Host tRNA pools became more GC-rich during HCV infection, whereas JEV retained variants more stably.
Why this matters globally
The work can improve reporter viruses for antiviral screening, mechanism studies and research vaccine platforms, but GC must be considered with RNA structure, codon pairs, innate immunity and biosafety.
Thai researcher contribution
Sarun Tulakarnwong and Sarin Chimnaronk of Mahidol University and Siriraj joined a Japanese collaboration on virus–host compatibility, contributing Thai RNA and structural-biology expertise.
Limitations to consider
Reporter and cell-culture results depend on insertion site, cell line and passage conditions. Three viruses cannot establish a universal rule, and GC recoding alters multiple mechanisms simultaneously.
Verify the original sources
Journal of VirologyRead the original article↗DOI: 10.1128/jvi.00882-26