Dynamic organization of Herpesvirus glycoproteins on the viral envelope revealed by super-resolution microscopy

Frauke Beilstein (1) , Gary H. Cohen (2) , Roselyn J. Eisenberg (3) , Valérie Nicolas (4) , Audrey Esclatine (1) , David Pasdeloup (1, 5)

1 I2BC - Institut de Biologie Intégrative de la Cellule
2 Department of Microbiology
3 Department of Pathobiology [Philadelphia]
4 IPSIT - Ingénierie et Plateformes au Service de l'Innovation Thérapeutique
5 UMR ISP - Infectiologie et Santé Publique

The processes of cell attachment and membrane fusion of Herpes Simplex Virus 1 involve many different envelope glycoproteins. Viral proteins gC and gD bind to cellular receptors. Upon binding, gD activates the gH/gL complex which in turn activates gB to trigger membrane fusion. Thus, these proteins must be located at the point of contact between cellular and viral envelopes to interact and allow fusion. Using super-resolution microscopy, we show that gB, gH/gL and most of gC are distributed evenly round purified virions. In contrast, gD localizes essentially as clusters which are distinct from gB and gH/gL. Upon cell binding, we observe that all glycoproteins, including gD, have a similar ring-like pattern, but the diameter of these rings was significantly smaller than those observed on cell-free viruses. We also observe that contrary to cell-free particles, gD mostly colocalizes with other glycoproteins on cell-bound particles. The differing patterns of localization of gD between cell-free and cell-bound viruses indicates that gD can be reorganized on the viral envelope following either a possible maturation of the viral particle or its adsorption to the cell. This redistribution of glycoproteins upon cell attachment could contribute to initiate the cascade of activations leading to membrane fusion.

Domaines: Sciences du Vivant [q-bio]

Frauke Beilstein, Gary H. Cohen, Roselyn J. Eisenberg, Valérie Nicolas, Audrey Esclatine, et al.. Dynamic organization of Herpesvirus glycoproteins on the viral envelope revealed by super-resolution microscopy. PLoS Pathogens, 2019, 15 (12), 21 p. ⟨10.1371/journal.ppat.1008209⟩. ⟨hal-02399551⟩