Research We study the spatio-temporal signaling events that regulate cell morphogenesis and cell fate decisions. The main hypothesis relevant to our research is that these signaling events are highly dynamic, are precisely regulated in time and space, and can be highly heterogeneous within distinct cells of a population. An important current limitation in our field is that this spatio-temporal resolution of signaling is missed in classic biochemical methods that average populations of thousands of cells, or that rely on the analysis of static, steady-states. To address these challenges, we devise novel quantitative approaches to measure/manipulate signaling dynamics at biologically relevant time/length scales. This includes: 1. Designing and using genetically-encoded biosensors that report on signaling dynamics in single living cells; 2. Microfabrication techniques that mimic geometric features of extracellular environments and induce in vivo relevant cellular behaviors, or allow us to dynamically perturb our cellular systems; 3. Computer vision/statistical image analysis methods to quantify the complex datasets we generate; 4. Mathematical modeling approaches to provide biological insight into these complex cellular systems. We specifically use these technologies to study Rho GTPase signaling regulating cell migration and neuronal differentiation, receptor tyrosine kinase signaling regulating cell fate decisions, and the process of local mRNA translation. Our multidisciplinary approach is likely to provide novel insights that will allow us to tackle a variety of pathologies including nervous system regeneration, neurodegeneration, metastatic cancer or drug resistance. Our approach might also allow us to efficiently manipulate stem cell fate.