Understanding the molecular mechanisms that shape an effective cellular response is a fundamental question in biology. While much is known about the chain of events initiated by membrane receptor-ligand binding, there is a fundamental gap in our understanding of how protein dynamics facilitate signaling. The long-term goal of my research program is to understand how the dynamic and stochastic behavior of protein-protein interactions is integrated to produce an efficient signaling response. The objective of this proposal is to quantify protein dynamics during the early events of membrane-associated signaling. Our central hypothesis is that the duration of protein-protein interactions modulates the signaling outcome. The rationale for the proposed research is that in order to understand signal transduction, it is critical to determine the sequence, lifetime and sub-cellular localization of biochemical events that initiate signaling. We use unique and innovative imaging techniques to provide quantitative information on the dynamics of early signaling events that cannot be obtained using traditional biochemical (population-based) techniques. We will apply our unique tool box, including state-of-the-art microscopy methods, biophysical and functional read-outs, in an integrated approach to provide a comprehensive picture of how protein-protein dynamics regulate tyrosine kinase signaling downstream of growth factor receptors and immunoreceptors. The proposed research is significant because the quantitative information that we will obtain has not been directly measured before and will bring new perspectives to cell biological processes, both in normal and disease states. By connecting the activation state of cell surface receptors with their dynamics, signaling partner interplay and downstream signaling events, we will are filling in critical spatiotemporal gaps in our models of cell signaling.
This proposal is relevant to public health since cell signal transduction is critical for regulating normal cellular processes and, when dysregulated, leads to diseases including cancer and allergy. In order to further our fundamental understanding of cell signaling, we will quantify protein interactions and dynamics at the molecular level using innovative imaging techniques. Therefore, the proposal is relevant to the part of NIH's mission that is in pursuit of fostering fundamental creative discoveries, innovative research strategies, and their applications to biomedical problems.
