Live Imaging of cAMP Signaling in D. discoideum Based on a Bioluminescent Indicator, Nano-lantern (cAMP).

Bioluminescence imaging of cellular function is a promising strategy. It has advantages over fluorescence imaging such as high sensitivity, no phototoxicity or no autofluorescence, and compatibility to deep-tissue imaging or optogenetics. However, functional imaging of cellular signaling by bioluminescence is not so easy due to the limited availability of bright bioluminescent indicators.Here we describe a detailed strategy to detect cellular cAMP dynamics by using Nano-lantern (cAMP1.6), one of the brightest bioluminescent indicator for cAMP . Both induced and spontaneous cAMP signaling in social amoeba, with a large and small signal change, respectively, were imaged by this method.