We use 2-hybrid approaches to demonstrate that RACK1 and β-arrestin2 inhibit the dimerization of PDE4D5.
Serine-to-alanine mutations at PKA and ERK1/2 phosphorylation sites on PDE4D5 detectably ablate dimerization.
RACK1 interacts with both the monomeric and dimeric forms, but β-arrestin2 interacts exclusively with the monomeric form.