Overview of the results
To analyze our performance in CASP14 we used several accuracy measures designed to evaluate various features of multimeric models. For the overall model evaluation we used QS-score, a distance-based measure of interface accuracy36. To make qualitative model accuracy assignments we converted QS-score values to CAPRI-like accuracy categories37. Four other scores were used to assess the interface and the overall structure accuracy. Interface Contact Similarity (ICS or F1-score) and Interface Patch Similarity (IPS or Jaccard coefficient) were used to assess contact and interface patch prediction, respectively13. Oligomeric lDDT and TM-score were used to assess overall structure accuracy. LDDT is an all-atom superposition-free score38, whereas TM-score is based on the rigid body superposition of Cα atoms39, 40. In addition to the above scores reported by the Prediction Center, we also used CAD-score31, 32 to evaluate the accuracy of both structure and interface accuracy.
The summary of our modeling results based on QS-score is presented in Table 1, whereas the detailed accuracy evaluation of our best models is provided in Supplementary Table S1. As can be seen in Table 1, for 11 targets we identified multimeric templates and used comparative modeling, producing medium or high-accuracy models for 8 of them. In the absence of reliable target-template sequence-structure alignments, we applied template-based docking using TM-align. This approach resulted in models of medium accuracy for 2 targets. Hybrid approaches utilizing both comparative modeling and docking steps were used for 9 targets with relative success. The results of free docking were ranging from completely incorrect to medium accuracy models. The custom modeling procedure that we used for coiled-coils did not produce any reliable models.