PROTACs (Proteolysis-targeting chimeric molecules) artificially hijack the components of the UPS to degrade a target protein. PROTAC drugs are hetero-bifunctional small molecules that contain two functional ligands connected via a linker; one ligand binds to a target protein and the other ligand binds to an E3 ligase. Bringing these two entities into proximity theoretically leads to polyubiquitylation and proteasomal degradation of the target protein. However, given the complexity this scenario does not always play out, and the PROTAC discovery strategy faces several challenges and pitfalls. To address these challenges, LifeSensors developed high-throughput tools for monitoring both polyubiquitylation and degradation of a target protein. Measuring ubiquitylation of a protein in a plate-based format accelerates PROTAC-based drug discovery. We have developed several platforms that enable rapid, quantitative monitoring of in vitro as well as cellular ubiquitylation.
Protein Degradation Assays
PROTACs (PROteolysis TArgeting Chimeras) are heterobifunctional molecules with a distinct ligand that targets a specific E3 ligase which is tethered by another ligand specific for the target protein, using an optimized chemical linker. This allows to exploit cell’s own degradation machinery (Ubiquitin proteasome system) to degrade target proteins.
PROTAC Ubiquitination Assays
PROTACs (PROteolysis Targeting Chimeras) are heterobifunctional molecules with a distinct ligand that targets a specific E3 ligase which is tethered by another ligand specific for the target protein, using an optimized chemical linker. Current PROTAC discovery heavily rely on monitoring Ternary complex formation using biophysical and biochemical approaches like TR-FRET proximity ligand assays and SPR that does not monitor true function of PROTAC i.e., PROTAC mediated ubiquitination.
Target Exploration and Validation
At LifeSensors we offer comprehensive overview of endogenous target protein expression, generate cell lines with a degrader tag (dTAG, BromoTAG®) on target protein of interest and induce selective degradation with TAGged protein of interest that can elucidate role of target in physiological function or a disease mechanism to produce relevant phenotype.
Novel E3 Ligases for PROTAC
Lifesensors has developed a suite of assays that can screen for novel ligands and design PROTACs recruiting novel ligases and aid in the discovery of new generation of PROTACs. Currently, LifeSensors has a library of ~30 ligases that can be explored for PROTAC applications.
PROTAC Ternary Complex Assays
Ternary complex formation with ubiquitination potential is crucial in accurately characterizing PROTAC efficiency and helping chemists rationally design. LifeSensors offers wide array of services to validate PROTAC ternary complex, PROTAC ubiquitination and determining binding affinities (SPR).