Bridging non-overlapping reads illuminates high-order epistasis between distal protein sites in a GPCR.

ABSTRACT: Epistasis emerges when the effects of an amino acid depend on the identities of interacting residues. This phenomenon shapes fitness landscapes, which have the power to reveal evolutionary paths and inform evolution of desired functions. However, there is a need for easily implemented, high-throughput methods to capture epistasis particularly at distal sites. Here, we combine deep mutational scanning (DMS) with a straightforward data processing step to bridge reads in distal sites within genes (BRIDGE). We use BRIDGE, which matches non-overlapping reads to their cognate templates, to uncover prevalent epistasis within the binding pocket of a human G protein-coupled receptor (GPCR) yielding variants with 4-fold greater affinity to a target ligand. The greatest functional improvements in our

SUBMITTER: Yoo JI 

PROVIDER: S-EPMC7000732 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature