Investigating dual-function PKA anchoring proteins

AKAP signaling islands constrain protein kinase A (PKA) and other effector proteins at specific regions of the cell. PKA anchoring is mediated by protein-protein interactions between the docking and dimerization domain of the regulatory subunits and an amphipathic helix of the AKAP. Preferential binding of the type I or the type II regulatory subunits to distinct AKAPs has been proposed as a mechanism to differentially compartmentalize PKA holoenzyme subtypes.  I study the interaction between AKAPs and the different PKA subtypes. I measure the affinity of AKAPs for the PKA subtypes in situ, with the technique fluorescence recovery after photobleaching (FRAP). This biophysical technique facilitates the comparison of AKAP-anchored and unanchored PKA’s mobility. I am interested in comparing the anchoring capacity of selective and “dual-functional” AKAPs in living cells, and then investigating the structural features that bestow them with their PKA preferences. 

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