Small-Molecule Target Engagement in Cells Marc Schürmann, Petra Janning, Slava Ziegler, Herbert Waldmann  Cell Chemical Biology  Volume 23, Issue 4, Pages 435-441 (April 2016) DOI: 10.1016/j.chembiol.2016.03.008 Copyright © 2016 Elsevier Ltd Terms and Conditions

Figure 1 Approaches for Target Engagement in Cells Employing Labeled Ligands (A and B) Fluorescence (A) and bioluminescence (B) energy transfer (Bacart et al., 2008). (C) Affinity-based chemical proteomics for covalent ligands (Simon et al., 2013). (D) Ligand-directed protein labeling (Tsukiji and Hamachi, 2014). (E) Affinity-guided DMAP labeling (Tsukiji and Hamachi, 2014). (F) Enzyme fragment complementation assay. FP, fluorescent protein; Luc, luciferase; Nu, nucleophile; ePL, enhanced prolabel peptide; EA, enzyme acceptor. Cell Chemical Biology 2016 23, 435-441DOI: (10.1016/j.chembiol.2016.03.008) Copyright © 2016 Elsevier Ltd Terms and Conditions

Figure 2 Cellular Thermal Shift Assay (A–C) After incubation with a compound or a vehicle control, cells are aliquoted and heated to ten different temperatures. Aggregated proteins are subsequently precipitated by centrifugation. The remaining soluble protein fraction is analyzed either via mass spectrometry or immunoblotting. The mass spectrometric readout enables (A) thermal proteome profiling (TPP), the determination of (B) isothermal-dose-response relations (ITDR), or (C) time-resolved ITDR for thousands of proteins in parallel. Cell Chemical Biology 2016 23, 435-441DOI: (10.1016/j.chembiol.2016.03.008) Copyright © 2016 Elsevier Ltd Terms and Conditions