Targeted Protein Acetylation Through Chemically Induced Proximity

Abstract

Protein acetylation is a pervasive and reversible post-translational modification (PTM) that impacts various protein features including stability, localization, and interactions and regulates diverse cellular functions, including transcription, signal transduction, and metabolism. This process is orchestrated by “writer” lysine acetyltransferases (KATs) and “eraser” deacetylases (KDACs), and its dysregulation is implicated in a broad spectrum of diseases including cancer, metabolic syndromes, and immune disorders. However, dissecting the roles of specific acetylation events in live cells remains a challenge due to the lack of tools that enable precise, rapid, and reversible acetylation at defined protein sites.

To begin addressing these challenges, we recently developed AceTAG (acetylation tagging), a chemically induced proximity (CIP) platform for targeted protein acetylation in live cells. AceTAG molecules are heterobifunctional ligands that recruit endogenous KATs─such as p300/CBP or PCAF/GCN5─to a tagged protein of interest, enabling selective, tunable, and dynamic acetylation. We demonstrated the utility of AceTAG across diverse proteins, including histone H3.3, p65/RelA, and p53. We further show that chemically induced acetylation of p53, including multiple hotspot p53 mutants, leads to enhanced stability and transcriptional activation, underscoring the potential of AceTAG for functional investigations and the potential for therapeutic exploration.

In this Account, we provide an overview of protein acetylation and survey chemical biology technologies for its manipulation, with a focus on AceTAG. We describe the conceptual motivation of AceTAG, applications, technical considerations, and recent efforts to expand this concept to endogenous proteins. Finally, we offer a forward-looking perspective of targeted acetylation as a chemical tool to investigate the biology of this PTM, as well as its potential as a therapeutic modality.