A model of the hantavirus surface glycoprotein lattice Hantaviruses are the causative agents of Hantaviruses are rodent-borne viruses distributed worldwide. two serious zoonotic diseases for which no They are classified as Old World and New World hantaviruses depending on their geographical distribution and natural treatment is available. They are enveloped reservoirs [1]. They are transmitted to humans via inhalation of viruses covered by an outer lattice formed aerosols contaminated with infected rodent excreta, causing by two glycoproteins termed Gn and Gc, two different severe diseases; haemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS) which are the perfect targets to develop with fatality rates of up to 12% (HFRS) and 40% (HPS). Despite hantavirus countermeasures. We determined the severity of these diseases, no efficient treatment is available. the x-ray crystal structures of a heterodimer The Hantaviridaeconstitute one of 12 families of the order of Gc and the Gn head, and a homotetramer Bunyavirales. The viral genome is composed of three segments of the Gn base using data collected from of ssRNA of negative-polarity. The medium segment encodes a the Proxima beamlines and combined them polyprotein precursor that is further processed in the endoplasmic with a cryoelectron tomography map at 11Å reticulum to yield two glycoproteins, termed Gn and Gc. Gn interacts co-translationally with the membrane fusion protein Gc to resolution to obtain a detailed model of the form a metastable Gn/Gc heterodimer [2]. The protomers further surface glycoprotein shell. We also revealed associate into (Gn/Gc) tetrameric spikes that are transported4 to the site of particle morphogenesis, where lateral interaction a built-in mechanism controlling Gc insertion between adjacent spikes induce the membrane curvature required into cellular membranes for fusion. These for budding new virions. Hantavirus particles are internalized results pave the way for immunogen design into target cells via receptor-mediated endocytosis, and the outer lattice then reacts to the acidic pH of the endosomes to protect against pathogenic hantaviruses. and drive the fusion of viral and cellular membranes through a conformational change of Gc. FIGURE 1 52