Rigid Protein-Protein Docking via Equivariant Elliptic-Paraboloid Interface Prediction
Ziyang Yu, Wenbing Huang, Yang Liu
TL;DR
This paper addresses rigid protein-protein docking by predicting a pair of elliptic paraboloid interfaces for the unbound proteins and docking via interface alignment. It introduces EPIT, a pairwise $SE(3)$-equivariant GNN that yields invariant and equivariant features for global interaction modeling, followed by a four stage interface fitting pipeline that converts to standard forms and computes a relative pose. The key contributions are the elliptic paraboloid interface model with independent equivariance, the EPIT back end for robust cross protein interactions, and a training objective that enforces accurate interface fitting and non overlap during docking. The proposed ElliDock achieves the fastest inference among baselines and remains competitive with state of the art on antibody-antigen docking, demonstrating practical value for rapid docking in drug design and protein engineering.
Abstract
The study of rigid protein-protein docking plays an essential role in a variety of tasks such as drug design and protein engineering. Recently, several learning-based methods have been proposed for the task, exhibiting much faster docking speed than those computational methods. In this paper, we propose a novel learning-based method called ElliDock, which predicts an elliptic paraboloid to represent the protein-protein docking interface. To be specific, our model estimates elliptic paraboloid interfaces for the two input proteins respectively, and obtains the roto-translation transformation for docking by making two interfaces coincide. By its design, ElliDock is independently equivariant with respect to arbitrary rotations/translations of the proteins, which is an indispensable property to ensure the generalization of the docking process. Experimental evaluations show that ElliDock achieves the fastest inference time among all compared methods and is strongly competitive with current state-of-the-art learning-based models such as DiffDock-PP and Multimer particularly for antibody-antigen docking.
