Identification of Potential Binding Region of Annexin II and Dengue Virus Envelop Glycoprotein

The tissue tropism of a virus is a key determinant of viral pathogenicity which is often modulated by the presence or absence of appropriate molecules on the surface of a host cell that can be used by the virus to gain entry into that cell. Annexin II was seen to interact with dengue virus (DENV) and enhanced infection. Herein, we aimed to explore this interaction as a potential target for the design of anti-DENV therapeutics. We demonstrated annexin II extracellular translocation in Vero cells upon exposure to DENV, extracellular and intracellular colocalization assays as well as co-immunoprecipitation assay were performed to further confirmed protein interaction. Molecular docking and molecular dynamic (MD) simulation were employed to identify the interaction sites. The result showed extracellular translocation of annexin II upon DENV exposure to the cell, the result further showed annexin II colocalizing with DENV E-glycoprotein extracellularly and intracellularly. Furthermore, the result of co-immunoprecipitation assay shows DENV E glycoprotein pulling down annexin II, and the result of molecular docking showed strong interaction between the two proteins. MD simulations has proposed the binding of two regions of annexin II (i) Y274-K280 and (ii) K369-Q327 with BR3 E glycoprotein of DENV2 (residue 380-389), with potential of infections abrogation upon inhibition.