HMPV Protein, Human (HEK293, His)

The Fusion glycoprotein F0 is an inactive precursor undergoing cleavage to generate the mature F1 and F2 fusion glycoproteins, representing a class I viral fusion protein. According to the current model, the protein exhibits at least three conformational states: the pre-fusion native state, pre-hairpin intermediate state, and post-fusion hairpin state. In viral and plasma cell membrane fusion events, the coiled coil regions adopt a trimer-of-hairpins structure, aligning the fusion peptide in close proximity to the C-terminal region of the ectodomain. The formation of this structure drives apposition and subsequent fusion of viral and cellular membranes, facilitating the delivery of the nucleocapsid into the cytoplasm. Remarkably, this fusion process is pH independent and occurs at either the plasma or endosomal membrane. The trimer of F1-F2 (F protein) also plays a critical role in host cell attachment by binding to host heparan sulfate, highlighting its multifaceted role in mediating viral entry and infection.