Epigenetic Regulation Mechanisms in Viral Infections: A Special Focus on COVID-19

The outbreak of Coronavirus Disease-2019 (Covid-19), caused by a novel and highly pathogenic coronavirus (severe acute respiratory syndrome coronavirus-2, SARS-CoV-2), is a persisting global health concern. Research so far has successfully identified the molecular mechanisms of viral entry, alterations within the host cell upon infection, and the stimulation of an immune response to fight it. One of the most important cellular regulatory machineries within the host cell to be affected by the SARS-CoV-2 infection is epigenetic regulation, which modulates transcriptional activity by DNA sequence-independent factors such as DNA-methylation, RNA interference and histone modifications. Several studies in the literature have previously reported epigenetic alterations within the host due to infections of the Coronaviridae family viruses including SARS-CoV and MERS-CoV that antagonized immune system activation. Recent studies have also identified epigenetic dysregulation of host metabolism by SARS-CoV-2 infection, linking epigenetic mechanisms with the pathophysiology and illness severity of Covid-19. Therefore, this book chapter aims to provide a comprehensive overview of the epigenetic regulation mechanisms in viral infections with a special focus on SARS-CoV-2 infection.