Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.11.378646v1?rss=1 Authors: Lee, W. H., Liu, W., Fan, J.-S., Yang, D. Abstract: The viral protease domain (NS3pro) of dengue virus is essential for virus replication and its cofactor NS2B is indispensable for the proteolytic function. Although several NS3pro-NS2B complex structures have been obtained, the dynamic property of the complex remains poorly understood. Using NMR relaxation techniques, here we found that NS3pro-NS2B exists in both closed and open conformations which are in dynamic equilibrium on a sub-millisecond timescale in aqueous solution. Our structural information indicates that the C-terminal region of NS2B is disordered in the open conformation but folded in the closed conformation. Using mutagenesis, we showed that the closed-open conformational equilibrium can be shifted by changing NS2B stability. Moreover, we revealed that the proteolytic activity of NS3pro-NS2B correlates well with the population of the closed conformation. Our results suggest that the closed-open conformational equilibrium can be used by both nature and man to control the replication of dengue virus. Copy rights belong to original authors. Visit the link for more info