Abstract
Two closely related acetyltransferases, p300 and its paralog CBP, are important regulators of gene expression and protein modulators in higher eukaryotes, influencing a wide array of cellular processes, including cell division, growth, DNA replication and repair, and apoptosis. The broad cellular impact is underscored by p300/CBP's capacity to interact with hundreds of proteins through various domains and the capability to acetylate numerous substrates and ubiquitinate selected targets. This intricate network of interactions and modifications highlights the essential role of p300/CBP in orchestrating cellular responses to pathological and physiological stimuli, thereby necessitating precise regulatory mechanisms to maintain their activity and substrate specificity. The regulation of p300/CBP is primarily governed by protein interactions and posttranslational modifications, including acetylation and ubiquitination, with autoregulation serving as a vital component in sustaining their enzymatic functions. The significance of tightly controlled p300/CBP activity is further emphasized by its association with various diseases, including Rubinstein-Taybi syndrome, Menke-Hennekam syndrome, and numerous cancers. Furthermore, the potential of p300/CBP as a therapeutic target has sparked interest in developing specific inhibitors. This review aims to elucidate the complex regulatory mechanisms of p300/CBP, focusing on posttranslational modifications, intermolecular interactions, and their implications in disease. A comprehensive understanding of the molecular foundations of p300/CBP regulation is essential for unraveling their roles in cellular processes and advancing targeted therapeutic strategies.