A Gammacoronavirus, Avian Infectious Bronchitis Virus, and an Alphacoronavirus, Porcine Epidemic Diarrhea Virus, Exploit a Cell Survival Strategy by Upregulating cFOS To Promote Virus Replication
Li Xia Yuan, Jia Qi Liang, Qing Zhu, Guo Dai, Shumin Li, To Sing Fung, Ding Xiang Liu
Abstract
The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by a newly emerged zoonotic coronavirus (SARS-CoV-2), highlights the importance of coronaviruses as human and animal pathogens and our knowledge gaps in understanding the cellular mechanisms, especially mechanisms shared among human and animal coronaviruses, exploited by coronaviruses for optimal replication and enhanced pathogenicity. This study reveals that upregulation of cFOS, along with other AP-1 transcription factors, as a cell-survival strategy is such a mechanism utilized by coronaviruses during their replication cycles. Through induction and regulation of apoptosis of the infected cells at early to intermediate phases of the replication cycles, subtle but appreciable differences in coronavirus replication efficiency were observed when the expression levels of cFOS were manipulated in the infected cells. As the AP-1 transcription factors are multi-functional, further studies of their regulatory roles in proinflammatory responses may provide new insights into the pathogenesis and virus-host interactions during coronavirus infection.