Epstein-Barr Virus Envelope Glycoprotein gp42 (None)

Epstein-Barr virus (EBV) envelope glycoprotein gp42 is a viral membrane protein essential for the fusion and entry of EBV into host B-lymphocytes. It plays a critical role in mediating the attachment of the virus to B cells and triggering membrane fusion, which allows viral entry. Gp42 binds specifically to human leukocyte antigen (HLA) class II molecules on B lymphocytes, serving as an essential receptor for EBV infection of these cells. The binding of gp42 to HLA class II triggers conformational changes that facilitate subsequent interactions with other viral glycoproteins, leading to membrane fusion and viral entry. Gp42 works in concert with other EBV envelope glycoproteins—gH/gL and gB. While gB executes the actual membrane fusion event, gHgL and gp42 regulate this process; all are required for successful infection of B cells. It has a flexible N-terminal region responsible for binding to the gH/gL complex, and a C-terminal domain adopts a C-type lectin-like fold (CTLD), which mediates binding to HLA class II molecules on target cells.

Inhibiting the interaction between gp42 and HLA class II molecules, or disrupting the gp42-gH/gL complex, could prevent viral entry.