Structure-Based Mutations in the Herpes Simplex Virus 1 Glycoprotein B Ectodomain Arm Impart a Slow-Entry Phenotype

Fan, Qing; Kopp, Sarah J.; Connolly, Sarah A.; Longnecker, Richard

In addition to mediating membrane fusion and binding to HS, gB is proposed to interact with gH/gL. In the current model of entry, gD binding to an entry receptor gB Mutations That Impact Fusion ® relays a signal to gH/gL that is transmitted to gB to trigger fusion (31) . To explore whether the defects in gB 3A function are due to a deficiency in its gH/gL interaction, we used a cell-cell fusion assay that allowed us to titrate increasing levels of gH/gL DNA (Fig. 9 ). If the gB 3A fusion defect is due to a reduced capacity to interact with the fusion regulator gH/gL, higher levels of gH/gL expression might compensate for the defect. Transfection with high levels of gH/gL DNA did not enhance fusion mediated by gB 3A, and thus, the hypothesis that gB 3A has impaired an interaction with gH/gL was not supported.