Shining light on location-biased cAMP signaling.

cAMP is the indispensable second messenger regulating cell metabolism and function in response to extracellular hormones and neurotransmitters. cAMP is produced via the activation of G protein–coupled receptors located at both the cell surface and inside the cell. Recently, Tsvetanova et al. explored cAMP generation in distinct locations and the impact on respective cell functions. Using a phospho-proteomic analysis, they provide insight into the unique role of localized cAMP production in cellular phospho-responses.