Molecular modeling and molecular dynamics simulation study of the human Rab9 and RhoBTB3 C-terminus complex.

Rab9 is required for the transport of mannose 6-phosphate receptors to the trans-Golgi network from late endosomes through the interaction with its effector: RhoBTB3. Earlier research indicates the C-terminus of RhoBTB3 (Rho_Cterm) is used for the interaction with Rab9. We used the homology modeling along with the molecular dynamics (MD) simulation to study the binding pattern of Rho_Cterm and Rab9 at atomic level. Both modeled structures, Rab9 and Rho_Cterm, are of high quality as suggested by the Ramachandran plot and ProCheck. The complex of Rab9-Rho_Cterm was generated by unrestrained pairwise docking using ZDOCK server. The interface of complex is consistent with the previous experimental data. The results of MD simulation indicate that the binding interface is stable along the simulation process.