Forms homotetramers with glycoprotein N at the surface of the virion. Attaches the virion to host cell receptors including integrin ITGAV/ITGB3. This attachment induces virion internalization predominantly through clathrin-dependent endocytosis. Class II fusion protein that promotes fusion of viral membrane with host endosomal membrane after endocytosis of the virion. Homodimer. Homotetramer; forms heterotetrameric Gn-Gc spikes in the pre-fusion conformation (By similarity). Homotrimer; forms homotrimer in the post-fusion conformation at acidic pH (By similarity). Interacts (via C-terminus) with the nucleoprotein (By similarity). The C-terminus is necessary for proper localization in the Golgi (By similarity). The cytoplasmic tail is involved in binding to the nucleocapsid (By similarity). Envelope polyprotein precursor is quickly cleaved in vivo just after synthesis, presumably by host signal peptidase. Belongs to the hantavirus envelope glycoprotein family.