Human parainfluenza virus 3 fusion protein (PIV3 F protein)

The human parainfluenza virus 3 fusion protein (PIV3 F protein) is a trimeric class I fusion glycoprotein expressed on the viral envelope. It is initially synthesized as an inactive precursor (F0) that is cleaved by host proteases to generate the fusogenic subunits F1 and F2. Upon activation, it undergoes a dramatic conformational change, inserting a fusion peptide into the host cell membrane and driving fusion of viral and cellular membranes[6][7]. This process is essential for viral entry and infectivity. The F protein is a critical target for neutralizing antibodies, some of which specifically recognize a metastable prefusion conformation, thus informing modern vaccine design strategies[1][2][3][5]. Due to its key role in membrane fusion and viral infectivity, it is a primary target for antivirals, neutralizing antibodies, and vaccine candidates. The structural plasticity of the F protein, its sequence conservation, and its activation by host proteases all impact the immune response and therapeutic strategies against human parainfluenza virus 3 infection[3][5][7].

Other names

Parainfluenza virus type 3 fusion proteinHPIV3 F proteinhPIV3 FF protein (PIV3)

Neutralizing antibodies prevent conformational changes in F protein, blocking membrane fusion and viral entry[1][2][3]\nProtease inhibitors block cleavage of F0 precursor, inhibiting activation and virus infectivity[7]