MS Defense Talk by Dr. Qinxin Pan
Inferring Protein Structural Contacts from the Evolutionary Record -- the Advantage of Considering Amino-Acid Identities
Covariance between amino acid at different residues of a protein family has been used to infer structural contacts. Different from conventional covariance-based approaches, direct-coupling analysis (DCA) is designed to disentangle direct and indirect correlations, enabling it to predict contacts accurately. Here, we show that in addition to the co-occurrence pattern between residues, the amino-acid identities underlying the residue pairs also provide information for structural contact prediction. We propose a framework that takes both evolutionary record and amino-acid identities into account and achieves better prediction accuracy than DCA across many protein families. In addition, we extend this framework to a recently emerged contact definition that is more structurally informative than previous ones. The contacts predicted by our approach could serve as reliable guides for protein structure prediction.