A H2S-Specific Ultrasensitive Fluorogenic Probe Reveals TMV-Induced H2S Production to Limit Virus Replication.

Pang, Zhili; Ye, Haishun; Ma, Dejun; Tu, Xiaoqiang; Yi, Long; Xi, Zhen

Understanding the role of H 2 S in host defense mechanisms against RNA viruses may provide opportunities for the development of antivirals to combat viral infections. Here, we have developed a green-emitting fluorogenic probe, which exhibits a large fluorescence response at 520 nm (> 560-fold) when treated with 100 µM H 2 S for 1 h. It is highly selective for H 2 S over biothiols (> 400-fold F / F 0 ) and has a detection limit of 12.9 nM. We demonstrate the application of the probe for endogenous H 2 S detection in vivo for the understanding of its roles in antiviral host defense. Such virus-induced H 2 S inhibits viral replication by reducing gene expression of RNA-dependent RNA polymerase ( RdRp) and coat protein (CP). Additionally, a H 2 S donor GYY4137 showed significantly antiviral activity as ribavirin, a broad-spectrum drug against RNA viruses. Furtherly, we propose a possible molecular mechanism for the TMV-induced H 2 S biogenesis. This work provides a proof-of-principle in support of further studies identifying endogenous H 2 S and its donors as potential antivirals toward RNA viruses.