Hantaan virus glycoprotein complex (Gn-Gc) (Gn-Gc)

The Hantaan virus glycoprotein complex, known as Gn-Gc, forms the outer envelope spikes on hantavirus virions and mediates critical early infection steps. Encoded by the viral M segment as a precursor glycoprotein (GPC) that is cleaved into Gn (G1) and Gc (G2), the complex assembles into a lattice with four-fold symmetry on the pleomorphic viral membrane. Gn primarily handles host cell receptor recognition and attachment, facilitating clathrin-mediated endocytosis, while Gc acts as the class II membrane fusion protein that, in response to endosomal low pH (around 5.9-6.3), undergoes conformational changes to expose a hydrophobic fusion loop, insert into the host membrane, and drive viral-host membrane fusion for genome delivery. Crystal structures confirm Gc's post-fusion trimeric form with three β-barrel domains (I-III), disulfide bonds, and N-linked glycosylation stabilizing the assembly, while Gn's ectodomain structure shows conservation across hantaviruses. In Hantaan virus, the most prevalent pathogenic hantavirus causing hemorrhagic fever with renal syndrome, this complex is essential for entry into host cells like endothelial and immune cells. Neutralizing antibodies target conformational epitopes on Gn-Gc, blocking attachment or fusion, highlighting its role as a key antiviral target, though no approved drugs exist. The glycoproteins also interact with host nucleoprotein tails, potentially evading antiviral responses like PKR-mediated interferon induction.

Other names

Glycoproteins G1 and G2Glycoprotein precursor (GPC)G_N and G_CGn and Gc