Search for host factors involved in flavivirus life

Several arthropod species in Japan are capable of carrying and transmitting flaviviruses, posing a potential risk of flaviviral disease outbreaks following the introduction of these viruses into the country. Despite this threat, effective treatments for many flaviviral infections remain unavailable. A comprehensive understanding of host factors involved in the flavivirus life cycle is essential for elucidating the detailed mechanisms of viral replication and developing novel antiviral therapies. In this study, we employed two complementary approaches to identify host factors involved in flavivirus replication. First, we conducted a genome-wide CRISPR screen using Zika virus and Japanese encephalitis virus. This screen led to the identification of several candidate host factors, including OR11H12 and PDE6H. Second, we investigated the impact of microRNAs previously identified in Indonesia on dengue virus replication. Our findings revealed that miR-663b and miR-7848 exhibit proviral effects, particularly during the early stages of viral replication in Huh-7 cells. Further studies are necessary to elucidate the molecular mechanisms by which these candidate host factors regulate flavivirus replication.