Interactions between calmodulin, adenosine A2A, and dopamine D2 receptors

Gemma Navarro, Marisol S. Aymerich, Daniel Marcellino, Antoni Cortés, Vicent Casadó, Josefa Mallol, Enric I. Canela, Luigi Agnati, Amina S. Woods, Kjell Fuxe, Carmen Lluís, Jose Luis Lanciego, Sergi Ferré, Rafael Franco

Research output: Contribution to journalArticlepeer-review

59 Scopus citations


The Ca2+-binding protein calmodulin (CaM) has been shown to bind directly to cytoplasmic domains of some G protein-coupled receptors, including the dopamine D2 receptor. CaM binds to the N-terminal portion of the long third intracellular loop of the D2 receptor, within an Arg-rich epitope that is also involved in the binding to Gi/o proteins and to the adenosine A2A receptor, with the formation of A2A-D2 receptor heteromers. In the present work, by using proteomics and bioluminescence resonance energy transfer (BRET) techniques, we provide evidence for the binding of CaM to the A2A receptor. By using BRET and sequential resonance energy transfer techniques, evidence was obtained for CaM-A2A-D2 receptor oligomerization. BRET competition experiments indicated that, in the A2A-D2 receptor heteromer, CaM binds preferentially to a proximal C terminus epitope of the A2A receptor. Furthermore, Ca2+ was found to induce conformational changes in the CaM-A2A-D2 receptor oligomer and to selectively modulate A2A and D2 receptor-mediated MAPK signaling in the A2A-D2 receptor heteromer. These results may have implications for basal ganglia disorders, since A2A-D2 receptor heteromers are being considered as a target for anti-parkinsonian agents.

Original languageEnglish (US)
Pages (from-to)28058-28068
Number of pages11
JournalJournal of Biological Chemistry
Issue number41
StatePublished - Oct 9 2009
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Cell Biology
  • Molecular Biology


Dive into the research topics of 'Interactions between calmodulin, adenosine A2A, and dopamine D2 receptors'. Together they form a unique fingerprint.

Cite this