Reconstituting the self-organization of a minimal kinase/phosphatase system in vitro*

Lipid modifying kinases and phosphatases are crucial for signal transduction, cytoskeletal organization and membrane trafficking. Lipid distribution as well as kinase/phosphatase localization exhibit spatiotemporal dynamics in many instances, but the underlying mechanism and regulation as well as the impact on membrane properties and downstream effector proteins remain enigmatic. Recently, the Legionella pneumophila effector proteins MavQ and SidP, a phosphatidylinositol lipid kinase and phosphatase, respectively, have been shown to dynamically remodel ER membranes in the host cell. Here, we set out to reconstitute the self-organization of this minimal kinase/phosphatase system in vitro. Using supported lipid bilayers with phosphatidylinositol lipids we show that purified MavQ/SidP can self-organize into traveling surface waves in vitro. Interrogating the self-organization of this system in a controlled manner we aim to elucidate the underlying self-organization mechanism.