Our lab develops new approaches to visualize and control signaling in living cells. These tools enable us to ask how signaling and cell behavior are governed by the spatio-temporal dynamics of protein activity. We try to uncover basic principles of cell biology while studying clinically important cell behaviors including platelet production, the specificity of immune cell synapses and role of the tumor microenvironment. We aim to produce broadly applicable new approaches, currently including biosensor designs that minimally perturb signaling, means to control endogenous proteins with light, and engineering allosteric networks to control proteins with light or small molecules. This work includes methods dependent on novel bright dyes that report protein conformational changes. By precisely producing and visualizing transient, localized signaling events we ask quantitative questions about spatial and kinetic control of cell decision making. (Nature, 440:1069-1072, 2006; Nature PMC2766670, 2009; Nature Methods, 13(9): 755-8, 2016; Science. 354(6318):1441-1444, 2016; Nature Chem Biol PMC7388658, 2020).