A Bioluminescent Activity Dependent Platform, BLADe, for Converting Intracellular Activity to Photoreceptor Activation

Abstract

Genetically encoded sensors and actuators have advanced the ability to observe and manipulate cellular activity, yet few non-invasive strategies enable cells to directly couple their intracellular states to user-defined outputs. We promote a bioluminescent activity-dependent (BLADe) platform that facilitates programmable feedback through genetically encoded light generation. Using calcium (Ca{superscript 2}) flux as a model, we engineered a Ca{superscript 2}-dependent luciferase that functions as an activity-gated light source capable of photoactivating light-sensing actuators. As an initial demonstration of the versatility of this platform we present two separate use cases in neurons. In the first application, the presence of luciferin triggers Ca{superscript 2} dependent local illumination that provides activity dependent gene expression by activating a light-sensitive transcription factor. In the second application, neuronal activity-driven Ca{superscript 2} fluctuations via locally generated bioluminescence control neural dynamics through opsin activation in single cells, populations and intact tissue. BLADe can be expanded to couple any signal that bioluminescent enzymes can be engineered to detect with the wide variety of photosensing actuators. This modular strategy of coupling an activity dependent light emitter to a light sensing actuator offers, in principle, a generalizable framework for state dependent cell-autonomous control across biological systems.