The combination of gQ1 and gQ2 tetramer components of both HHV-6A/6B are important for viral propagation, probably by affecting attachment to their different receptors.
Both HHV-6A and HHV-6B have a glycoprotein H tetramer on the envelope consisting of glycoproteins gH/gL/gQ1/gQ2.
Wakata et al. of Kobe University Graduate School of Medicine investigated the necessity and function of each specific glycoprotein component of this envelope tetramer, for both HHV-6A and HHV-6B by swapping in and out each of the four components of the tetramer from each of the two viruses.
The data from these experiments indicates that gQ1/gQ2 from each of the two viruses are important in determining the tetramer’s affinity for their entry receptors, CD46 for HHV-6A (Santoro 1999), and CD134 for HHV-6B (Tang 2015), respectively. It also shows that replacement of gQ1 or gQ2 from one virus into the other impairs binding, as shown in Figure 1.
These meticulous studies continue to dissect the contribution of the difference components of the HHV-6A and HHV-6B glycoprotein H tetramer complex in the biology of the viruses.
Read the full article: Wakata 2021