Thousands of proteins in the human proteome are subjected to modification by reversible lysine acetylation, which is now recognized as a key regulator of diverse processes such as epigenetics and metabolism. The careful balance between the expression and activity of lysine acetyl transferases (KATs) and lysine deacetylases (KDACs) maintains the acetylome of a cell. Our long-term goal is to develop a mechanistic understanding of how lysine acetylation is controlled and how the mark effects cell state. Our current focus is to develop a new class of small molecule fluorescent chemical tools that report on lysine deacetylation activities in living cells with spatial resolution. We will deploy this new family of chemical tools to test the hypothesis that KDAC signaling is in part mediated by subcellular distribution, which controls access to substrates and local cofactors. This hypothesis could help explain some of the ambiguous results associated with lysine acetylation that have been observed, as the biological consequence of modulation of a specific KDAC isoform may be masked by other isoforms in a cell-type or disease specific manner. We postulate that a key to understanding how lysine acetylation is regulated is to monitor the overall amounts of KAT and KDAC activities with spatial-temporal resolution. Our primary biological interests right now deal with roles of KDACs outside of the nucleus, in particular in the mitochondria and the cytoplasm, while pursing mechanistic studies in the context of metabolism and breast cancer.
Chemical modifications of lysine residues on proteins are both drivers and markers of diverse diseases including cancer and metabolic disorders. Uncovering how these modifications are controlled in both healthy and diseased states will uncover new mechanisms of cellular function. We will develop a new set of reagents that allow us to watch these reactions with spatial- temporal resolution in live cells to uncover how the readers and writers of lysine modifications function, while studying models of breast cancer and obesity.
|Qiu, Tian; Kathayat, Rahul S; Cao, Yang et al. (2018) A Fluorescent Probe with Improved Water Solubility Permits the Analysis of Protein S-Depalmitoylation Activity in Live Cells. Biochemistry 57:221-225|
|Rauch, Simone; Dickinson, Bryan C (2018) Programmable RNA Binding Proteins for Imaging and Therapeutics. Biochemistry 57:363-364|
|Kathayat, Rahul S; Cao, Yang; Elvira, Pablo D et al. (2018) Active and dynamic mitochondrial S-depalmitoylation revealed by targeted fluorescent probes. Nat Commun 9:334|
|Pu, Jinyue; Kentala, Kaitlin; Dickinson, Bryan C (2018) Multidimensional Control of Cas9 by Evolved RNA Polymerase-Based Biosensors. ACS Chem Biol 13:431-437|
|Beck, Michael W; Kathayat, Rahul S; Cham, Candace M et al. (2017) Michael addition-based probes for ratiometric fluorescence imaging of protein S-depalmitoylases in live cells and tissues. Chem Sci 8:7588-7592|
|Pu, Jinyue; Zinkus-Boltz, Julia; Dickinson, Bryan C (2017) Evolution of a split RNA polymerase as a versatile biosensor platform. Nat Chem Biol 13:432-438|
|Pu, Jinyue; Dewey, Jeffrey A; Hadji, Abbas et al. (2017) RNA Polymerase Tags To Monitor Multidimensional Protein-Protein Interactions Reveal Pharmacological Engagement of Bcl-2 Proteins. J Am Chem Soc 139:11964-11972|
|Kathayat, Rahul S; Elvira, Pablo D; Dickinson, Bryan C (2017) A fluorescent probe for cysteine depalmitoylation reveals dynamic APT signaling. Nat Chem Biol 13:150-152|