The crystal structure of a simian Foamy Virus receptor binding domain provides clues about entry into host cells

Ignacio Fernández (1) , Lasse Toftdal Dynesen (2) , Youna Coquin (2) , Riccardo Pederzoli (1) , Delphine Brun (1) , Ahmed Haouz (3) , Antoine Gessain (2) , Félix A Rey (1) , Florence Buseyne (2) , Marija Backovic (1)

1 Virologie Structurale - Structural Virology
2 EPVO (UMR_3569 / U-Pasteur_3) - Epidémiologie et Physiopathologie des Virus Oncogènes / Oncogenic Virus Epidemiology and Pathophysiology
3 Cristallographie (Plateforme) - Crystallography (Platform)

The surface envelope glycoprotein (Env) of all retroviruses mediates virus binding to cells and fusion of the viral and cellular membranes. A structurefunction relationship for the HIV Env that belongs to the Orthoretrovirus subfamily has been well established. Structural information is however largely missing for the Env of Foamy viruses (FVs), the second retroviral subfamily. In this work we present the X-ray structure of the receptor binding domain (RBD) of a simian FV Env at 2.57 Å resolution, revealing two subdomains and an unprecedented fold. We have generated a model for the organization of the RBDs within the trimeric Env, which indicates that the upper subdomains form a cage-like structure at the apex of the Env, and identified residues K342, R343, R359 and R369 in the lower subdomain as key players for the interaction of the RBD and viral particles with heparan sulfate.

Domaines: Sciences du Vivant [q-bio]; Biologie structurale [q-bio.BM]

Ignacio Fernández, Lasse Toftdal Dynesen, Youna Coquin, Riccardo Pederzoli, Delphine Brun, et al.. The crystal structure of a simian Foamy Virus receptor binding domain provides clues about entry into host cells. Nature Communications, 2023, 14 (1), pp.1262. ⟨10.1038/s41467-023-36923-0⟩. ⟨pasteur-04035902⟩