Figure 2.

Hypothetical model for the regulation of 5-HT₇ receptor activity by dynamic palmitoylation. This model suggests existence of two different receptor populations: Palmitoylated receptors with two additional intracellular C-terminal loops (left) and non-palmitoylated receptors with no intracellular C-terminal loops (right). These populations exist in dynamic equilibrium regulated by basal or agonist-promoted palmitate turnover. Depalmitoylation results in significant increase of the receptor’s capacity to convert from the inactive (R) to the active (R*) form in the absence of an agonists. Palmitoylated receptor shows activation of both Gα_s- and Gα₁₂-proteins (left). Non-palmitoylated receptor possesses increased agonist-independent, constitutive activity (R*) towards Gα_s-mediated signaling, while basal receptor-mediated activation of Gα₁₂-protein is unaltered (right).