Figure 1.

A model for the epigenetic regulation of involvement of Par-4 in the Ca²⁺ dependent Regulation of Dopamine D2 receptor (D2DR) Signaling. (A) Par-4/D2DR complex formation is necessary to maintain an inhibitory tone on dopamine-mediated cAMP signaling generated by D2DR in the low Ca²⁺ condition. (B) Chronic stress disrupts Par-4/D2DR interaction and may facilitate calmodulin/D2DR complex formation upon Ca²⁺ influx; hence, an upregulation of dopamine-cAMP-CREB signaling, which may contribute to the increased intensity of depression-like behaviors.

Note: Identification of Par-4/D2DR interaction potentially reveals a mechanism for crosstalk between Ca²⁺ signaling and dopamine-mediated cAMP signaling.