UAS regulates expression of the N-terminal part (i.e. the A-kinase anchoring protein (AKAP) docking domain) of Pka-R2, but deleted for the first 13-most N-terminal amino acids that are essential for function of the docking domain - this prevents the N-terminal peptide competing with endogenous full-length Pka-R2 for AKAP-binding sites. (Compare with P{UAS-eCOPR2}.)