This is a membrane-permeable phosphoducin-like anti-β? peptide, whose membrane-permeable sequence (MPS) is derived from the C-terminal residues of phosducin-like protein (PhLP). This region of PhLP has been shown to confer interactions with Gβ?-mediated signaling. Specifically, it was shown to have inhibitory effects on Go GTPase activity, demonstrating the ability to bind Gβ?, and inhibition of Gβ?-enhanced rhodopsin phosphorylation by βARK. The PhLP shares amino acid sequence homology with phosphoducin, a phosphoprotein expressed in the retina and pineal gland. These proteins have been shown to regulate G-protein signaling by binding to the beta-gamma subunits of G proteins.