Virus-derived Synthetic Riboswitches for Real-time Coronaviruses Sensing in Live Cells

Real-time sensing of viral infection in live cells are crucial for virology research and antiviral development. However, existing methods face challenges of low signal sensitivity and the necessity for viral manipulation and cell fixation. Here, we develop a viral riboswitch (vRibo) approach that employs the viral replicase to induce transgene expression upon viral infection. The vRibo is designed to detect viral real-time transcription and replication in live cells, which in response triggers the translation of reporter and therapeutic genes. By integrating a viral packaging sequence, vRibo can be transmitted to neighboring cells through progeny virions, effectively acting as a "Trojan Horse". The negative-strand vRibo elements demonstrated effective detection of several coronaviruses, including 229E and OC43, due to the conservation of cis-acting RNA structures across coronaviruses. Notably, vRibo functions as a dual-purpose system, acting both as an infection detector and inducible antiviral system. vRibo has the potential for basic virology research applications and can be adopted in improving the inducible expression of mRNA medicines for future coronaviruses. ### Competing Interest Statement L.S.Q. is a founder of Epic Bio and scientific advisor of Laboratory of Genomic Research and Kytopen Corp.