We are interested in the spatiotemporal control of cell signaling, with a particular focus on important signaling molecules such as protein kinases and second messengers.

Compartmentalization of kinase activities is widely conjectured to be a key determinant in the specificity of various signaling pathways. In order to achieve direct measurement of kinase activities, we developed a general strategy for monitoring protein phosphorylation in living cells based on fluorescence resonance energy transfer (FRET). We are currently applying several kinase reporters to investigate the spatiotemporal regulation or dysregulation of protein kinases (e.g. PKA, Akt) in cell migration, energy metabolism and cancer development. Quantitative measurement from live-cell fluorescence imaging will be combined with mechanistic computational modeling for systems analyses of signaling networks regulated by kinases.

New technology is being developed to achieve large-scale multi-dimensional profiling of kinases by integrating high-throughput capability with dynamic measurement of kinase activity. In a related endeavor, we are developing a live-cell high-throughput screening method for identification of new drug leads targeting kinases.

In addition, to decipher the cellular information encoded in the spatiotemporal dynamics of second messengers, we set out to develop and apply biochemical and biophysical tools that allow us to monitor and perturb their dynamics with precise spatial and temporal control.

The application of these novel technologies for studying kinases and their regulators should provide a better understanding of the molecular changes that regulate the cells’ inner workings, adding time and space dimensions and dynamic information to the current map of signal transduction networks.