InterPep2: Global Peptide-Protein Docking with Structural Templates

MotivationInteractions between proteins and peptides or peptide-like intrinsically disordered regions are involved in many important biological processes, such as gene expression and cell life-cycle regulation. Experimentally determining the structure of such interactions is time-consuming, and because of the disordered nature of the ligand, the interactions are especially difficult to predict through software, requiring specialized solutions. Although several prediction-methods exist, most are limited in performance or availability.\n\nResultsInterPep2 is a freely available method for predicting the structure of peptide-protein interactions. We have previously shown that structural templates can be used to accurately predict peptide-protein binding sites, and that using templates from regular protein-protein interactions will increase the number of sites found. Here, we show that the same principle can be extended to dock the peptide to the binding surface using InterPep2. A key component of InterPep2 is the ability to score plausible interaction templates using a RandomForest trained to predict the DockQ-score using sequence and structural features. InterPep2 is tested on a difficult dataset of 251 peptide-protein complexes, where it correctly positions 136 (54%) at the correct site compared to 114 (45%) for the second best method. Analyzing the confidence score InterPep2 recalls more true positives across all specificity levels compared to the second best method, for example at 10% False Positive Rate it correctly identifies 59% of the complexes compared to 44% for the second best method.\n\nAvailabilityThe program is available from: http://wallnerlab.org/InterPep\n\nContactBjorn Wallner bjorn.wallner@liu.se