Intramolecular signaling in tandem-GAF domains from PDE5 and PDE10 studied with a cyanobacterial adenylyl cyclase reporter

►Sequence specificity of linker between GAF-A and B in phosphodiesterases 5 and 10. ►Modeling of linker region along structure of phosphodiesterase 2. ►Linker mutations identify structural requirements for intramolecular signaling.