Updated project metadata. we used hydrogen deuterium exchange masss spec (HDX-MS) to define the exchange kinetics of PLC-y1 as it interacts with the kinase domain of FGFR1, and liposomes containing PIP2, in order to understand how PLC-y isozymes operate at membranes. We show that the binding of FGFR1k to PLC-y1 increases deuterium incorporation within the interface between the regulatory domains and the catalytic core. Importantly, the addition of liposomes further increase deuterium exchange within the same region.