Revealing virus-host membrane fusion mechanisms using optical tweezers

Ebola virus (EBOV) is an enveloped virus that must fuse with the host cell membrane in order to release its genome and initiate infection. This process requires the action of the trimeric envelope glycoprotein (GP), encoded by the virus, which resides in the viral envelope. Each protomer in the GP trimer consists of a receptor binding subunit, GP1, and a membrane fusion subunit, GP2. Following internalization by macropinocytosis, the EBOV virion is trafficked to the late endosome, where the host cathepsin proteases cleave GP1, leading to binding between GP and Niemann-Pick C1 (NPC1) receptor.