Research ArticleCompartmentalized Signaling

Direct Binding Between Orai1 and AC8 Mediates Dynamic Interplay Between Ca2+ and cAMP Signaling

Science Signaling  10 Apr 2012:
Vol. 5, Issue 219, pp. ra29
DOI: 10.1126/scisignal.2002299

You are currently viewing the abstract.

View Full Text
As a service to the community, AAAS/Science has made this article free with registration.


The interplay between calcium ion (Ca2+) and cyclic adenosine monophosphate (cAMP) signaling underlies crucial aspects of cell homeostasis. The membrane-bound Ca2+-regulated adenylyl cyclases (ACs) are pivotal points of this integration. These enzymes display high selectivity for Ca2+ entry arising from the activation of store-operated Ca2+ (SOC) channels, and they have been proposed to functionally colocalize with SOC channels to reinforce crosstalk between the two signaling pathways. Using a multidisciplinary approach, we have identified a direct interaction between the amino termini of Ca2+-stimulated AC8 and Orai1, the pore component of SOC channels. High-resolution biosensors targeted to the AC8 and Orai1 microdomains revealed that this protein-protein interaction is responsible for coordinating subcellular changes in both Ca2+ and cAMP. The demonstration that Orai1 functions as an integral component of a highly organized signaling complex to coordinate Ca2+ and cAMP signals underscores how SOC channels can be recruited to maximize the efficiency of the interplay between these two ubiquitous signaling pathways.

View Full Text