Post-translational modifications (PTMs) modify existing proteins with additional chemical functionalities, resulting in the mediation of signaling events underlying various cellular processes. The dysregulation of PTMs has been closely related to the onset and/or relapse of human diseases. Yet, many PTM-related non-histone proteins and enzymes remain to be elucidated in terms of their identity, functions, and roles in cellular activities such as activation, proliferation, and migration, simply due to the lack of tools for characterization.2 Despite the development of bioorthogonal chemical reactions such as “click chemistry”, few research programs have explored protein labeling or tagging with reduced sterics. Towards this end, my group has invented a steric-free bioorthogonal reaction (fluorine-thiol displacement (FTDR))1 and has developed a novel class of FTDR-based imaging and proteomics probes aimed at a complete dissection of substrate proteins of acetylation that are featured in diseased cells such as cancer cell lines; which for now cannot be systematically profiled due to limitations in the current chemical proteomics approach.1
Concurrently, to facilitate the studying and targeting of any new protein-protein interactions (PPIs) to be revealed by the aforementioned research investigations in PTM signaling, we also exploited other tool probes3-4 such as peptide stapling4 based on the FTDR reaction. The resulting peptides possessed improved folding, stability, and on-target affinity, but also displayed enhanced cell penetration than the peptides stapled by traditionally used ring-closing metathesis.4 As an on-going effort, my group has been applying this new class of peptides to interrogate Axin-β-catenin interactions and p53-MDM2 interactions that are key to the onset and relapse of breast cancers, leukemia, and lymphoma, etc, as well as PPIs of protein tyrosine phosphatases that are important to neuron regeneration.
References:
1. J. Am. Chem. Soc. 2021, 143 (3), 1341-1347.
2. J. Med. Chem. 2018, 61 (8), 3239-3252.
3. ACS Chem. Biol. 2018, 13 (4), 958-964.
4. Nat. Commun. 2022, 13(350).