Tyler Dao (MANALIS & SHALEK LABS)

Pooled Genetic Screens to Interrogate TCR Signaling Networks

The protein Linker for Activation of T cells (LAT) is a membrane-associated adapter required for signal amplification and diversification from the T cell receptor. The discovery of inducible protein interactions and higher-order assemblies mediated by LAT post-translational modifications and binding surfaces suggests that LAT is a platform regulating downstream pathways. To achieve a comprehensive picture of LAT molecular function, we demonstrate a high-content screen in which a series of mutants in the LAT protein are analyzed to characterize their effect on T cell activation.

David Kastner (WHITE & KULIK LABS)

Substrate Positioning Distinguishes Halogenases and Hydroxylases

Non-heme iron halogenases and hydroxylases are related metalloenzymes that catalyze the challenging C-H functionalization of a diversity of products. The re-engineering of halogenases to behave like halogenases and vice versa is a promising method of expanding their respective substrate scopes. However, initial efforts have yielded little success. Using molecular dynamics, we identified the angle of the substrate relative to the metal center as a key factor in reactivity and quantified energetic contributions of non-covalent interactions responsible for precise substrate positioning through quantum mechanical calculations.