Crystal structure of Usutu virus envelope protein in the pre-fusion state

Background Usutu virus (USUV) is a mosquito-born flavivirus that can infect multiple avian and mammalian species. The viral surface envelope (E) protein functions to initiate the viral infection by recognizing cellular receptors and mediating the subsequent membrane fusion, and is therefore a key virulence factor involved in the pathogenesis of USUV. The structural features of USUV-E, however, remains un-investigated thus far.